Written in Stone - Alexandra...
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0 500 1000 ft Carmel Formation Temple Cap Sandstone Navajo Sandstone Kaibab Formation TRIASSIC JURASSIC CRETACEOUS PERMIAN Moenave Fm Chinle Fm Moenkopi Fm Vermilion Cliffs White Cliffs Claron Formation Kaiparowits Formation Wahweap Formation Straight Cliffs Formation Tropic Shale Dakota Formation Kolob Terrace PENNSYLVANIAN MISSISSIPPIAN DEVONIAN CAMBRIAN PROTEROZOIC (PRECAMBRIAN) Canaan Peak Formation Toroweap Formation Coconino Sandstone Hermit Formation Esplanade Sandstone Wescogame Formation Manakacha Formation Watahomigi Formation Surprise Canyon Formation Redwall Limestone Temple Butte Limestone Muav Limestone Bright Angel Shale Tapeats Sandstone Grand Canyon Supergroup Vishnu Schist Shinarump- Chocolate Cliffs Arizona Strip Grand Canyon Colorado River 0 500 1000 ft Gray Cliffs Pink Cliffs Zion Canyon Bryce Canyon Supai Group Tonto Group 8000 - 9000' 7000' 6000' 5000' 6000' 7000' 10 miles Vertical exaggeration ~ 1 1 / 2 5000' sea level Cambrian, Devonian, Mississippian Cretaceous Tertiary 1 mile Pennsylvanian - Permian Triassic - Jurassic Proterozoic 7000' 7000' 5000' sea level Vermilion Cliffs White Cliffs Shinarump- Chocolate Cliffs Arizona Strip Grand Canyon Colorado River Gray Cliffs Pink Cliffs Bryce Canyon Kanab 1500' ALEOCENE - EOCENE P Constant Change he landscape surrounding Tropic hasn’t always looked like it does today. ough the rocky cliffs and canyons around you may seem fixed and unchanging, that’s only because their transformation is so slow. Imagine that you could watch the last few billion years of this land’s history condensed into a few hours. You’d see a dizzying rush of change—oceans overspreading the land, then receding. Desert sand dunes advancing, then giving way to lush tropical forests. Vast freshwater lakes forming and drying up. Land upliſting and eroding. e land’s geologic history lies before you like an open book—a book that is still being written. Each rock layer tells a different chapter of that dynamic story. Here on the Colorado Plateau, the rock layers didn’t get jumbled as the plateau upliſted, the way they have in many other upliſted regions. at makes it far easier to read a sequential story from the rock layers, since you can be fairly sure that the older layers lie beneath the younger ones. T Written in Stone View from Highway 12 in Tropic. Claron Formation Icing on the Cake tŚŝůĞ ĞdžƉůŽƌŝŶŐ ƚŚĞ ŽůŽƌĂĚŽ WůĂƚĞĂƵ ĚƵƌŝŶŐ ƚŚĞ ϭϴϴϬƐ ŐĞŽůŽŐŝƐƚ ůĂƌĞŶĐĞ ƵƩŽŶ ůŝŬĞŶĞĚ ŝƚ ƚŽ Ă ŐƌĞĂƚ ƐƚĂŝƌǁĂLJ ďĞĐĂƵƐĞ ŽĨ ŝƚƐ ƌĞŵĂƌŬĂďůĞ ƐĞƋƵĞŶĐĞ ŽĨ ĐůŝīƐ ĂŶĚ ƉůĂƚĞĂƵƐ ƌŝƐŝŶŐ ŵŽƌĞ ƚŚĂŶ ϲϬϬϬ ĨĞĞƚ ĨƌŽŵ ƚŚĞ ďŽƩŽŵ ŽĨ 'ƌĂŶĚ ĂŶLJŽŶ ƚŽ ƚŚĞ ƚŽƉ ŽĨ ƌLJĐĞ ĂŶLJŽŶ dŚĞ WŝŶŬ ůŝīƐ ĚƌĂŵĂƟĐĂůůLJ ƌĞǀĞĂůĞĚ ŝŶ ƌLJĐĞ ĂŶLJŽŶ EĂƟŽŶĂů WĂƌŬ ĂŶĚ WŽǁĞůů WŽŝŶƚ ĂƌĞ ƚŚĞ ƚŽƉŵŽƐƚ ƐƚĞƉ ŽĨ ƚŚŝƐ 'ƌĂŶĚ ^ƚĂŝƌĐĂƐĞͶƚŚĞLJƌĞ ƚŚĞ ŝĐŝŶŐ ŽŶ ƚŚĞ ůĂLJĞƌ ĐĂŬĞ ŽĨ ƚŚĞ ŽůŽƌĂĚŽ WůĂƚĞĂƵ Claron Formation dŚĞ ůĂƌŽŶ &ŽƌŵĂƟŽŶ ĨŽƌŵƐ ƚŚĞ ďƌĞĂƚŚƚĂŬŝŶŐ ƐƉŝƌĞƐ ĂŶĚ ĐůŝīƐ ŽĨ ƌLJĐĞ ĂŶLJŽŶ EĂƟŽŶĂů WĂƌŬ ĂŶĚ ŝdžŝĞ EĂƟŽŶĂů &ŽƌĞƐƚ dŚŝƐ ƌŽĐŬ ůĂLJĞƌ ďĞŐĂŶ forming about 50 million years ago, when an ŝŵŵĞŶƐĞ ĨƌĞƐŚǁĂƚĞƌ ůĂŬĞ ĐŽǀĞƌĞĚ ƚŚŝƐ ƌĞŐŝŽŶ >ĂŬĞ ůĞǀĞůƐ ĐŚĂŶŐĞĚ ŽǀĞƌ ƟŵĞ ĂŶĚ ƚŚĞƐĞ ǀĂƌLJŝŶŐ ĐŽŶĚŝƟŽŶƐ ƉƌŽĚƵĐĞĚ Ă ŵŝdž ŽĨ ůŝŵĞƐƚŽŶĞ ƐĂŶĚƐƚŽŶĞ ĂŶĚ ƐŝůƚƐƚŽŶĞ ŝŶ ƚŚŝƐ ĨŽƌŵĂƟŽŶ Straight Cliffs Formation ŝŐŚƚLJͲĮǀĞ ŵŝůůŝŽŶ LJĞĂƌƐ ĂŐŽ ůƵƐŚ ĐŽĂƐƚĂů ƐǁĂŵƉƐ ĂŶĚ ŵĂƌƐŚĞƐ ŝŶ ƚŚŝƐ ĂƌĞĂ ůĞŌ deposits of sand, mud, and plenty of ǀĞŐĞƚĂƟŽŶ KǀĞƌ ƟŵĞ ƚŚĂƚ ŽƌŐĂŶŝĐ ŵĂƩĞƌ ĨŽƌŵĞĚ ůĂLJĞƌƐ Žƌ ƐĞĂŵƐ ŽĨ ĐŽĂů Rock layers of the Grand Staircase, from the bottom of Grand Canyon (leſt) to the top of Bryce Canyon (right). e layers in the upper illustration are greatly stretched out to clearly show the strata. Illustration courtesy of Ron Blakey, Ancient Landscapes of the Colorado Plateau. Drawing from geologic evidence, this paleogeographic map depicts Utah some 50 million years ago, when the freshwater sediments of the Claron Formation were deposited. Credit: Ron Blakey, Ancient Landscapes of the Colorado Plateau. By carefully studying rock formations, geologists can “read” the land’s history. e map above shows what geologists believe North America looked like about 92 million years ago, when the marine sediments of the Tropic Shale layer were deposited. Credit: Ron Blakey, Ancient Landscapes of the Colorado Plateau. You Are Here From the vantage point of Arizona’s Kaibab Plateau, you can look north and see many of the “steps” of the Grand Staircase. Pink Cliffs White Cliffs Vermilion Cliffs Written in Stone You Are Here Tropic Shale Wahweap Formation Straight Cliffs Formation Tropic Shale 'ĞŽůŽŐŝƐƚƐ ĮƌƐƚ ŝĚĞŶƟĮĞĚ ƚŚĞ dƌŽƉŝĐ ^ŚĂůĞ ŚĞƌĞ ŝŶ dƌŽƉŝĐ hƚĂŚ dŚŝƐ ůĂLJĞƌ ĨŽƌŵĞĚ ĂďŽƵƚ ϵϯ ŵŝůůŝŽŶ LJĞĂƌƐ ĂŐŽ ǁŚĞŶ ƚŚŝƐ ƌĞŐŝŽŶ ůĂLJ ďĞŶĞĂƚŚ ƚŚĞ tĞƐƚĞƌŶ /ŶƚĞƌŝŽƌ ^ĞĂǁĂLJ ^ŝůƚ ĂŶĚ ĐůĂLJ ƉĂƌƟĐůĞƐ ƐĞƩůĞĚ ƚŽ ƚŚĞ ƐĞĂ ŇŽŽƌ ĂƐ ĚŝĚ ƚŚĞ ƐŚĞůůƐ ŽĨ ĐŽƵŶƚůĞƐƐ ŵĂƌŝŶĞ ĂŶŝŵĂůƐ KǀĞƌ ƟŵĞ ƚŚĞƐĞ ƐĞĚŝŵĞŶƚƐ ŚĂƌĚĞŶĞĚ ŝŶƚŽ ĨŽƐƐŝůͲƌŝĐŚ ƐŚĂůĞ dŽŐĞƚŚĞƌ ƚŚĞ dƌŽƉŝĐ ^ŚĂůĞ ^ƚƌĂŝŐŚƚ ůŝīƐ tĂŚǁĞĂƉ ĂŶĚ <ĂŝƉĂƌŽǁŝƚƐ ĨŽƌŵĂƟŽŶƐ ĐŽŶƚĂŝŶ ŽŶĞ ŽĨ ƚŚĞ ďĞƐƚ ĂŶĚ ŵŽƐƚ ĐŽŶƟŶƵŽƵƐ ƌĞĐŽƌĚƐ ŽĨ >ĂƚĞ ƌĞƚĂĐĞŽƵƐ ůŝĨĞ ŝŶ ƚŚĞ ǁŽƌůĚ Dakota Formation EŝŶĞƚLJͲĮǀĞ ŵŝůůŝŽŶ LJĞĂƌƐ ĂŐŽ ƚŚĞ tĞƐƚĞƌŶ /ŶƚĞƌŝŽƌ ^ĞĂǁĂLJ ǁĂƐ ƐůŽǁůLJ ƐƉƌĞĂĚŝŶŐ ĚŽǁŶ ƚŚƌŽƵŐŚ ƚŚĞ ŝŶƚĞƌŝŽƌ ǁĞƐƚĞƌŶ hŶŝƚĞĚ ^ƚĂƚĞƐ Ɛ ƚŚĞ ƐĞĂ ƌŽƐĞ ĂŶĚ ĨĞůů ƚŚŝƐ ƌĞŐŝŽŶ ǁĂƐ ǀĂƌŝŽƵƐůLJ ĐŽǀĞƌĞĚ ǁŝƚŚ ƐŚĂůůŽǁ ƐĂůƚ ǁĂƚĞƌƐ ůƵƐŚ ĐŽĂƐƚĂů ƐǁĂŵƉƐ ĂŶĚ ƐĂŶĚLJ ĞdžƉĂŶƐĞƐ ĞƚĐŚĞĚ ďLJ ƌŝǀĞƌƐ ĂŶĚ ƐƚƌĞĂŵƐ dŚĂƚƐ ǁŚLJ LJŽƵůů ĮŶĚ ƐĞǀĞƌĂů ĚŝīĞƌĞŶƚ ƐĞĚŝŵĞŶƚĂƌLJ ƌŽĐŬ ƚLJƉĞƐ ŝŶ ƚŚĞ ĂŬŽƚĂ &ŽƌŵĂƟŽŶͶŝŶĐůƵĚŝŶŐ ƐĂŶĚƐƚŽŶĞ ĐŽĂů ďĞŶƚŽŶŝƚĞ ĐůĂLJ ĂŶĚ ƐŚĂůĞ Wahweap Formation ^ǁĂŵƉLJ ĨƌĞƐŚǁĂƚĞƌ ůŽǁůĂŶĚƐ ĐŽǀĞƌĞĚ ƚŚŝƐ ĂƌĞĂ ϴϬ ŵŝůůŝŽŶ LJĞĂƌƐ ĂŐŽ ĚĞƉŽƐŝƟŶŐ ƐĂŶĚ Ɛŝůƚ ĐůĂLJ ĂŶĚ ƚŚĞ ƌĞŵĂŝŶƐ ŽĨ ĚĞĂĚ ĂŶŝŵĂůƐ dŚĞƐĞ became the fossil-rich layers of sandstone, shale, and mudstone of ƚŚĞ tĂŚǁĞĂƉ &ŽƌŵĂƟŽŶ Kaiparowits Formation During the Late Cretaceous, 75 million years ago, this region was a lush, subtropical, coastal plain inhabited by a fabulous array of animals, from tyrannosaurs to ǀĞůŽĐŝƌĂƉƚŽƌƐ dŚĞ ďŽŶĞƐ ŽĨ ŵĂŶLJ ŽĨ ƚŚĞƐĞ ĂŶŝŵĂůƐ ǁĞƌĞ ƉƌĞƐĞƌǀĞĚ in layers of mud and sand, forming an outstanding fossil ƌĞĐŽƌĚ ĨŽƌ ƚŚŝƐ ƉĞƌŝŽĚ Here in Tropic, you can only see the top- most geologic layers of the Grand Staircase. Gray Cliffs Chocolate Cliffs
Transcript of Written in Stone - Alexandra...
05001000 ft
Carmel Formation
Temple Cap SandstoneNavajo Sandstone
Kaibab Formation
TRIASSIC
JURASSIC
CRETACEOUS
PERMIAN
Moenave Fm
Chinle Fm
Moenkopi Fm
VermilionCliffs
White Cliffs
Claron Formation
Kaiparowits Formation
Wahweap Formation
Straight CliffsFormation
Tropic Shale
Dakota Formation
Kolob Terrace
PENNSYLVANIAN
MISSISSIPPIANDEVONIAN
CAMBRIAN
PROTEROZOIC(PRECAMBRIAN)
Canaan Peak Formation
Toroweap FormationCoconino SandstoneHermit Formation
Esplanade SandstoneWescogame Formation
Manakacha FormationWatahomigi Formation
Surprise Canyon FormationRedwall Limestone
Temple Butte LimestoneMuav Limestone
Bright Angel ShaleTapeats Sandstone
Grand Canyon SupergroupVishnu Schist
Shinarump-ChocolateCliffsArizona
StripGrand Canyon
Colorado River
05001000 ft Gray Cliffs
Pink Cliffs
Zion Canyon
Bryce Canyon
Supai Group
Tonto Group
8000 - 9000'
7000'6000'5000'6000'7000'
10 miles Vertical exaggeration ~ 1 1/2
5000'
sea levelCambrian, Devonian, Mississippian
CretaceousTertiary
1 mile
Pennsylvanian - Permian Triassic - Jurassic
Proterozoic
7000' 7000'
5000'sea level
VermilionCliffs
White CliffsShinarump-ChocolateCliffsArizona
Strip
Grand Canyon
Colorado River Gray CliffsPink Cliffs
Bryce Canyon
Kanab1500'
ALEOCENE - EOCENEP
Constant Change he landscape surrounding Tropic hasn’t always looked like it does today. Though the rocky cliffs and canyons around you may seem fixed and unchanging, that’s only because their transformation is so slow. Imagine that you could watch the last few billion years of this land’s history condensed into a few hours. You’d see a dizzying rush of change—oceans overspreading the land, then receding. Desert sand dunes advancing, then giving way to lush tropical forests. Vast freshwater lakes forming and drying up. Land uplifting and eroding.
The land’s geologic history lies before you like an open book—a book that is still being written. Each rock layer tells a different chapter of that dynamic story. Here on the Colorado Plateau, the rock layers didn’t get jumbled as the plateau uplifted, the way they have in many other uplifted regions. That makes it far easier to read a sequential story from the rock layers, since you can be fairly sure that the older layers lie beneath the younger ones.
T
Written in Stone
View from Highway 12 in Tropic.
Claron Formation Icing on the Cake
Claron Formation
forming about 50 million years ago, when an
Straight Cliffs Formation
deposits of sand, mud, and plenty of
Rock layers of the Grand Staircase, from the bottom of Grand Canyon (left) to the top of Bryce Canyon (right). The layers in the upper illustration are greatly stretched out to clearly show the strata. Illustration courtesy of Ron Blakey, Ancient Landscapes of the Colorado Plateau.
Drawing from geologic evidence, this paleogeographic map depicts Utah some 50 million years ago, when the freshwater sediments of the Claron Formation were deposited. Credit: Ron Blakey, Ancient Landscapes of the Colorado Plateau.
By carefully studying rock formations, geologists can “read” the land’s history. The map above shows what geologists believe North America looked like about 92 million years ago, when the marine sediments of the Tropic Shale layer were deposited. Credit: Ron Blakey, Ancient Landscapes of the Colorado Plateau.
You Are Here
From the vantage point of Arizona’s Kaibab Plateau, you can look north and see many of the “steps” of the Grand Staircase.
Pink Cliffs White Cliffs
Vermilion Cliffs
Written in Stone
You Are Here
Tropic Shale
Wahweap FormationStraight Cliffs Formation
Tropic Shale
Dakota Formation
Wahweap Formation
became the fossil-rich layers of sandstone, shale, and mudstone of
Kaiparowits FormationDuring the Late Cretaceous, 75 million years ago, this region was a lush, subtropical, coastal plain inhabited by a fabulous array of animals, from tyrannosaurs to
in layers of mud and sand, forming an outstanding fossil
Here in Tropic, you can only see the top-most geologic layers of the Grand Staircase.
Gray Cliffs
Chocolate Cliffs
![MAGMATIC INTRUSIONS INTO THE SULFUR-RICH CARMEL … · Ranney W. (2008) Ancient Landscapes of the Colorado Plateau. Grand Canyon Association. [22] Peterson F. (1994) Systems of the](https://static.fdocuments.net/doc/165x107/5f064c737e708231d4174b26/magmatic-intrusions-into-the-sulfur-rich-carmel-ranney-w-2008-ancient-landscapes.jpg)
