Mature Sandstones-ArenitesMature Sandstones-Arenites

QUARTZ ARENITESQUARTZ ARENITES

Quartz ArenitesQuartz Arenites Mistakenly referred to as orthoquartzitesMistakenly referred to as orthoquartzites Quartz Arenite is accepted termQuartz Arenite is accepted term Quartz arenite characteristicsQuartz arenite characteristics

Generally white or pink cemented with quartzGenerally white or pink cemented with quartz Calcite cement also commonCalcite cement also common Can get pressure solution between grainsCan get pressure solution between grains

Thin blanket sands or very thickThin blanket sands or very thickMonoxln qtz most commonMonoxln qtz most commonHigh proportion of undulatory quartz less commonHigh proportion of undulatory quartz less commonCan be cross bedded or contain ripple marksCan be cross bedded or contain ripple marksGenerally sorted and rounded--end point of Generally sorted and rounded--end point of

evolutionevolutionMay contain minor chert and heavy mineralsMay contain minor chert and heavy minerals

Quartz AreniteQuartz Arenite

VarietiesVarieties

Ist cycle--more polyxln amp Ist cycle--more polyxln amp undulatory qtz less rounded undulatory qtz less rounded more feldspar more diverse more feldspar more diverse heavy mineralsheavy minerals

Multi-cyclemdash well rounded Multi-cyclemdash well rounded sorted overgrowthssorted overgrowths

Bimodality in some--selective Bimodality in some--selective removal of fine sand or 2 sourcesremoval of fine sand or 2 sources

Polycrystalline quartz Polycrystalline quartz grain with sutured grain with sutured crystal-crystal crystal-crystal boundaries Such boundaries Such quartz is classified as quartz is classified as a unstable grain a unstable grain This quartz is This quartz is sourced from low- sourced from low-grade metamorphic grade metamorphic rocks(Young 1976) rocks(Young 1976)

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

QUARTZ ARENITESQUARTZ ARENITES

Quartz ArenitesQuartz Arenites Mistakenly referred to as orthoquartzitesMistakenly referred to as orthoquartzites Quartz Arenite is accepted termQuartz Arenite is accepted term Quartz arenite characteristicsQuartz arenite characteristics

Generally white or pink cemented with quartzGenerally white or pink cemented with quartz Calcite cement also commonCalcite cement also common Can get pressure solution between grainsCan get pressure solution between grains

Thin blanket sands or very thickThin blanket sands or very thickMonoxln qtz most commonMonoxln qtz most commonHigh proportion of undulatory quartz less commonHigh proportion of undulatory quartz less commonCan be cross bedded or contain ripple marksCan be cross bedded or contain ripple marksGenerally sorted and rounded--end point of Generally sorted and rounded--end point of

evolutionevolutionMay contain minor chert and heavy mineralsMay contain minor chert and heavy minerals

Quartz AreniteQuartz Arenite

VarietiesVarieties

Ist cycle--more polyxln amp Ist cycle--more polyxln amp undulatory qtz less rounded undulatory qtz less rounded more feldspar more diverse more feldspar more diverse heavy mineralsheavy minerals

Multi-cyclemdash well rounded Multi-cyclemdash well rounded sorted overgrowthssorted overgrowths

Bimodality in some--selective Bimodality in some--selective removal of fine sand or 2 sourcesremoval of fine sand or 2 sources

Polycrystalline quartz Polycrystalline quartz grain with sutured grain with sutured crystal-crystal crystal-crystal boundaries Such boundaries Such quartz is classified as quartz is classified as a unstable grain a unstable grain This quartz is This quartz is sourced from low- sourced from low-grade metamorphic grade metamorphic rocks(Young 1976) rocks(Young 1976)

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Quartz AreniteQuartz Arenite

VarietiesVarieties

Ist cycle--more polyxln amp Ist cycle--more polyxln amp undulatory qtz less rounded undulatory qtz less rounded more feldspar more diverse more feldspar more diverse heavy mineralsheavy minerals

Multi-cyclemdash well rounded Multi-cyclemdash well rounded sorted overgrowthssorted overgrowths

Bimodality in some--selective Bimodality in some--selective removal of fine sand or 2 sourcesremoval of fine sand or 2 sources

Polycrystalline quartz Polycrystalline quartz grain with sutured grain with sutured crystal-crystal crystal-crystal boundaries Such boundaries Such quartz is classified as quartz is classified as a unstable grain a unstable grain This quartz is This quartz is sourced from low- sourced from low-grade metamorphic grade metamorphic rocks(Young 1976) rocks(Young 1976)

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

VarietiesVarieties

Ist cycle--more polyxln amp Ist cycle--more polyxln amp undulatory qtz less rounded undulatory qtz less rounded more feldspar more diverse more feldspar more diverse heavy mineralsheavy minerals

Multi-cyclemdash well rounded Multi-cyclemdash well rounded sorted overgrowthssorted overgrowths

Bimodality in some--selective Bimodality in some--selective removal of fine sand or 2 sourcesremoval of fine sand or 2 sources

Polycrystalline quartz Polycrystalline quartz grain with sutured grain with sutured crystal-crystal crystal-crystal boundaries Such boundaries Such quartz is classified as quartz is classified as a unstable grain a unstable grain This quartz is This quartz is sourced from low- sourced from low-grade metamorphic grade metamorphic rocks(Young 1976) rocks(Young 1976)

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Polycrystalline quartz Polycrystalline quartz grain with sutured grain with sutured crystal-crystal crystal-crystal boundaries Such boundaries Such quartz is classified as quartz is classified as a unstable grain a unstable grain This quartz is This quartz is sourced from low- sourced from low-grade metamorphic grade metamorphic rocks(Young 1976) rocks(Young 1976)

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Monocrystalline Quartz GrainMonocrystalline Quartz Grain

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

OriginOrigin

Are supermature sheet-like mostly on margins of cratonAre supermature sheet-like mostly on margins of craton Probably have eolian historyProbably have eolian history Look for bimodalityLook for bimodality Beach depositional environment possibleBeach depositional environment possible Some are marine--marine fossils interbedded with limestone Some are marine--marine fossils interbedded with limestone

amp dolomiteamp dolomite Most deposited in shallow marine environmentMost deposited in shallow marine environment May be trangressive sheet sands--Therefore shallow marine--May be trangressive sheet sands--Therefore shallow marine--

clays winnowed outclays winnowed out Conditions to form sandsConditions to form sands i removal of feldspars--weatheringtransporti removal of feldspars--weatheringtransport ii removal of clayii removal of clay iii rounding of quartziii rounding of quartz

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Beach Environment-Mussel Beach Environment-Mussel Rock CARock CA

High EnergyHigh Energy Usually well sortedUsually well sorted Usually well Usually well

roundedrounded Lacks finesLacks fines

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Sinuous barchanoidal transverse dunes on a transgressive dunefield Sinuous barchanoidal transverse dunes on a transgressive dunefield in an arid environment at Guerrero Negro Baja California Mexico in an arid environment at Guerrero Negro Baja California Mexico

Photograph by Patrick HespPhotograph by Patrick Hesp httpwwwgeomorphorggalmslatteryworldhtmlhttpwwwgeomorphorggalmslatteryworldhtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Navajo SandstoneNavajo Sandstone

Coconino County Coconino County AZAZ

Nearly pure quartzNearly pure quartz Note large scale Note large scale

cross bedscross beds

USGS

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

St Peters SandstoneSt Peters Sandstone

Crossbedded St Crossbedded St Peter Sandstone in Peter Sandstone in roadcut along State roadcut along State Route 39 near Route 39 near center of NW14 center of NW14 sec 1 T 4N R 5 sec 1 T 4N R 5 E Iowa County E Iowa County WisconsinWisconsin

Ordovician Ordovician

USGS

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Freshly exposed Freshly exposed St Peter St Peter sandstone US sandstone US Silica Quarry in Silica Quarry in Pacific MOPacific MO

httpwwwrollanetorg~conorwcwomearticle2829amp30combinedhtm

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Ordovician PaleogeographyOrdovician Paleogeography

Note craton covered Note craton covered by shallow seasby shallow seas

Note demarcation of Note demarcation of equatoreequatore

St Peters sandstone St Peters sandstone deposited in these deposited in these shallow seasshallow seas

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Cambrian quartz Cambrian quartz arenite of the Mt arenite of the Mt Simon and Simon and Wonewoc Wonewoc Formation is Formation is exposed along exposed along bedding planes bedding planes

Deposited along a Deposited along a sandy equatorial sandy equatorial beach beach

wwwuwspeduhefferanMosineeFossilshtml

Must remove unstable minerals to be Must remove unstable minerals to be arenitearenite

Quartz Quartz CementationCementation

Two phases of cementation - This is a quartz sandstone seen under plain light The quartz grains have quartz overgrowths (labeled o) reflecting a first phase of cementation and then later a period of carbonate cementation (c) seen as a brownish material filling the pore space

httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_16htm

Calcite CementCalcite Cement

(Peter Kresan from Understanding Earth Press amp Siever)

ldquoldquoImmaturerdquo rocksImmaturerdquo rocks

(Mineralogically (Mineralogically unstable)unstable)

Enriched in Enriched in feldspars andfeldspars and

Unstable rock Unstable rock fragmentsfragments

Immature Siliciclastic SedimentImmature Siliciclastic Sediment

Is usually more Is usually more diversediverse

(mineralogy-wise) (mineralogy-wise) thanthan

mature sedimentmature sediment Grains includeGrains include

Plagioclase feldsparPlagioclase feldspar OrthoclaseOrthoclase MicroclineMicrocline MicasMicas LithicsLithics QuartzQuartz

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Quartz Quartz CementationCementation

Two phases of cementation - This is a quartz sandstone seen under plain light The quartz grains have quartz overgrowths (labeled o) reflecting a first phase of cementation and then later a period of carbonate cementation (c) seen as a brownish material filling the pore space

httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_16htm

Calcite CementCalcite Cement

(Peter Kresan from Understanding Earth Press amp Siever)

ldquoldquoImmaturerdquo rocksImmaturerdquo rocks

(Mineralogically (Mineralogically unstable)unstable)

Enriched in Enriched in feldspars andfeldspars and

Unstable rock Unstable rock fragmentsfragments

Immature Siliciclastic SedimentImmature Siliciclastic Sediment

Is usually more Is usually more diversediverse

(mineralogy-wise) (mineralogy-wise) thanthan

mature sedimentmature sediment Grains includeGrains include

Plagioclase feldsparPlagioclase feldspar OrthoclaseOrthoclase MicroclineMicrocline MicasMicas LithicsLithics QuartzQuartz

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Calcite CementCalcite Cement

(Peter Kresan from Understanding Earth Press amp Siever)

ldquoldquoImmaturerdquo rocksImmaturerdquo rocks

(Mineralogically (Mineralogically unstable)unstable)

Enriched in Enriched in feldspars andfeldspars and

Unstable rock Unstable rock fragmentsfragments

Immature Siliciclastic SedimentImmature Siliciclastic Sediment

Is usually more Is usually more diversediverse

(mineralogy-wise) (mineralogy-wise) thanthan

mature sedimentmature sediment Grains includeGrains include

Plagioclase feldsparPlagioclase feldspar OrthoclaseOrthoclase MicroclineMicrocline MicasMicas LithicsLithics QuartzQuartz

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

ldquoldquoImmaturerdquo rocksImmaturerdquo rocks

(Mineralogically (Mineralogically unstable)unstable)

Enriched in Enriched in feldspars andfeldspars and

Unstable rock Unstable rock fragmentsfragments

Immature Siliciclastic SedimentImmature Siliciclastic Sediment

Is usually more Is usually more diversediverse

(mineralogy-wise) (mineralogy-wise) thanthan

mature sedimentmature sediment Grains includeGrains include

Plagioclase feldsparPlagioclase feldspar OrthoclaseOrthoclase MicroclineMicrocline MicasMicas LithicsLithics QuartzQuartz

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Immature Siliciclastic SedimentImmature Siliciclastic Sediment

Is usually more Is usually more diversediverse

(mineralogy-wise) (mineralogy-wise) thanthan

mature sedimentmature sediment Grains includeGrains include

Plagioclase feldsparPlagioclase feldspar OrthoclaseOrthoclase MicroclineMicrocline MicasMicas LithicsLithics QuartzQuartz

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

General Arkose DescriptionGeneral Arkose Description

Typically pink amp coarse grained may Typically pink amp coarse grained may be white fgr be white fgr Polyxln quartz dominatesPolyxln quartz dominates Feldspar usually k-spar (microcline)Feldspar usually k-spar (microcline) Kaolinization of feldspars commonKaolinization of feldspars common Angular and poor to moderate sorting Angular and poor to moderate sorting May have calcite cement and some matrixMay have calcite cement and some matrix

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

ArkoseArkose

Originally --rock with qtz and feldsparOriginally --rock with qtz and feldsparRe-defined-- sandstone with gt25 Re-defined-- sandstone with gt25

feldsparfeldspar Feldspars from granitegneiss sourceFeldspars from granitegneiss source

No agreement on feldspar contentNo agreement on feldspar content 25 usually cited25 usually cited

Folk--subarkose = 10-25 feldsparFolk--subarkose = 10-25 feldspar

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Arkose ndash greater than 25 FelsparArkose ndash greater than 25 Felspar Usually compositionally immature Usually compositionally immature

to submatureto submature Usually texturally submatureUsually texturally submature Idicates rapid uplift erosion and Idicates rapid uplift erosion and

deposition for feldspars to survivedeposition for feldspars to survive

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Hand specimens Imature siliciclastic Hand specimens Imature siliciclastic sandstonessandstones(arkose - litharenite)(arkose - litharenite)

Arkose (basalt-derived)

Arkose (granite-derived)

Litharenite (igneoussedimentaryderived)

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lithic FragmentsLithic Fragments

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

ArkoseArkose

Note twinned plagNote twinned plag Note interwoven Note interwoven

texture of kspartexture of kspar Rock has matrixRock has matrix

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

ArkoseArkose

750 m

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Arkose types Arkose types

Residual--in situ disintegration of Residual--in situ disintegration of graniticgneissic rocksgraniticgneissic rocks

Arkosic Arenite--reworked by riversea Arkosic Arenite--reworked by riversea generally well sorted matrix free grains generally well sorted matrix free grains

may be rounded may be rounded

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Deposition Deposition

Deposition in fluvial lacustrine or transitional Deposition in fluvial lacustrine or transitional marinemarine wedge-shaped (fan or apron) adjacent to upliftswedge-shaped (fan or apron) adjacent to uplifts thin and interbedded with lacustrine or marine thin and interbedded with lacustrine or marine

environmentenvironment

Arkoses interbedded with marinenon-marineArkoses interbedded with marinenon-marine eg conglomerates shales limestones amp eg conglomerates shales limestones amp

evaporitesevaporites channels plant fragments trough cross-bedding channels plant fragments trough cross-bedding

= fluvial env = fluvial env

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Alluvial FansAlluvial Fans

Fan-shaped Fan-shaped depositsdeposits

of siliciclasticof siliciclasticsediment depositedsediment depositedat the base ofat the base ofmountainsmountains

Gravel to clay sizedGravel to clay sized Angular to sub Angular to sub

roundedrounded immatureimmature

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Alluvia FansAlluvia Fans

1048729 Best developed in arid regions1048729 Best developed in tectonically active areas

From Walker RG 1980 Facies Models Geological Association of Canada

Lateral fining

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Braided StreamBraided Stream

Note meandering Note meandering and adjacent and adjacent braided streambraided stream

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

httpwwwusouthaledugeologyhaywickGY402402-pp14pdf

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

OriginOrigin

Mostly first cycleMostly first cyclePlagioclase arkoses from volcanic Plagioclase arkoses from volcanic

sourcesourceNeed cold or arid climate for feldspar Need cold or arid climate for feldspar

preservationpreservation humid climate bad for feldsparshumid climate bad for feldspars

D Need rapid uplift and erosionD Need rapid uplift and erosion 1 under these conditions feldspar 1 under these conditions feldspar

preservable in humid climatepreservable in humid climate

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

2399

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

VI) ExamplesVI) Examples Devonian Old Red sandstone-England Precambrian Devonian Old Red sandstone-England Precambrian

Torridon sandstone-ScotlandTorridon sandstone-Scotland Silurian Clinton Fm-Pennsylvania Silurian Clinton Fm-Pennsylvania

Old Red Sandstone Siccar Point

1778 Hutton studied outcrop and recognized the great expanse of geologic time

Near-vertical greywackes of the Silurian Gala Group were unconformably Overlain by the younger gently-dipping sandstones of the Devono-Carboniferous Stratheden Group (Upper Old Red Sandstone) httpwwwhgsorgenarticlesprintviewasp

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InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

InterpretationsInterpretations Tyee Formation Tyee Formation

(Eocene Oregon (Eocene Oregon Coast Range) -Coast Range) - This This sandstone was sandstone was deposited late during deposited late during an adjacent orogeny an adjacent orogeny and shows evidence and shows evidence of a source area that of a source area that includes quartz (q) includes quartz (q) plagioclase (f) plagioclase (f) potassium feldspar potassium feldspar (f(k) stained here to (f(k) stained here to straw yellow color) straw yellow color) muscovite (m) and muscovite (m) and biotite (b) all of which biotite (b) all of which suggest that the suggest that the source area was source area was granitic pluton that granitic pluton that contained micas The contained micas The large Lv grain large Lv grain suggests that arc suggests that arc volcanic rocks were volcanic rocks were also exposed in the also exposed in the source area source area httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm

Lookingglass Formation Lookingglass Formation (Eocene Oregon Coast (Eocene Oregon Coast Range) -Range) - This sandstone was This sandstone was deposited below the Tyee deposited below the Tyee Formation (last slide) and Formation (last slide) and shows a somewhat different shows a somewhat different source area These grains source area These grains include quartz (q) include quartz (q) feldsparlate during an feldsparlate during an adjacent orogeny and shows adjacent orogeny and shows evidence of a source area that evidence of a source area that includes quartz (q) includes quartz (q) plagioclase (f) many plagioclase (f) many sedimentary lithic grains (Ls sedimentary lithic grains (Ls that are likely from a shale that are likely from a shale source or a phylliteslate source or a phylliteslate source) and several heavy source) and several heavy mineral grains (h) This mineral grains (h) This composition differs from the composition differs from the volcanic arc derived Tyee volcanic arc derived Tyee Formation and suggests the Formation and suggests the source area for this sandstone source area for this sandstone involved rocks that were involved rocks that were probably laid down on the sea probably laid down on the sea floor (shales) and were later floor (shales) and were later uplifted into an active orogen uplifted into an active orogen The heavy minerals may The heavy minerals may indicate metamorphism in the indicate metamorphism in the source area that would also source area that would also be consistent with orogeny be consistent with orogeny httpfacultygguwyoeduhellerSed20Strat20ClassSedStratL1slideshow_1_12htm