Hydrothermal Vent Deposits on Hydrothermal Vent Deposits on the Seafloorthe Seafloor

An International Decade of Ocean An International Decade of Ocean Exploration: 1970Exploration: 1970--19801980

Gary Gary McMurtryMcMurtry

Presentation OutlinePresentation Outline•• Overview of submarine hydrothermal systemsOverview of submarine hydrothermal systems

•• Metalliferous Metalliferous sediments: prelude to discoverysediments: prelude to discovery

•• Origins of LowOrigins of Low--T hydrothermal depositsT hydrothermal deposits

•• Discovery of HighDiscovery of High--T systems: seafloor ores?T systems: seafloor ores?

•• Volatiles recycling at Volatiles recycling at subduction subduction zones & the zones & the Geostill Geostill ConceptConcept

Schematic Section of Ocean Crust at Ridge AxisSchematic Section of Ocean Crust at Ridge Axis

McMurtry (1981)

Section of Altered Basalt and Autoradiograph,Section of Altered Basalt and Autoradiograph,ODP Drill Hole, ODP Drill Hole, Cocos Cocos RidgeRidge

Andrews & McMurtry (1979)

Li, BMap

RockSection

Section of Altered Basalt and Autoradiograph,Section of Altered Basalt and Autoradiograph,ODP Drill Hole, ODP Drill Hole, Cocos Cocos RidgeRidge

Andrews & McMurtry (1979)

Li, BMap

RockSection

Location of Galapagos Rift Vent FieldLocation of Galapagos Rift Vent Field

First Dives of ALVIN to Galapagos Rift, 1978First Dives of ALVIN to Galapagos Rift, 1978

$50K NGS Photo

Unique vent Biota: Unique vent Biota: ““Spagetti Spagetti WormsWorms””

Unique vent Biota: Unique vent Biota: ““Chemosynthetic ClamsChemosynthetic Clams””

ALVIN temperatureALVIN temperatureProbe: Note milky, lowProbe: Note milky, low--T T water full of bacteria and water full of bacteria and elemental sulfur particleselemental sulfur particles

The hydrothermal The hydrothermal vent crabvent crab, , Bythograea Bythograea thermydronthermydron, is a top , is a top predator at predator at ventvent sites sites in the Pacific Oceanin the Pacific Ocean

Hot Brines & Recent Heavy Metal Deposits in the Red SeaHot Brines & Recent Heavy Metal Deposits in the Red Sea

From: Degens & Ross (1970)

Atlantis II Deep Brine PoolAtlantis II Deep Brine Pool

From: Degens & Ross (1970)

Sections of Piston Cores Sections of Piston Cores into Hot Brine Pool Sedimentsinto Hot Brine Pool Sediments

Sediments contain:Sediments contain:

Amorphous silicaAmorphous silica (light brown)(light brown)Nontronite Nontronite (dark brown clay)(dark brown clay)AnhydriteAnhydrite (white (white pptppt))SulfidesSulfides of Fe, Cu, Zn & of Fe, Cu, Zn & PbPb(black (black ppt ppt with traces of Ag with traces of Ag and Au)and Au)

Degens & Ross (1970)

Metalliferous Metalliferous Sediments on the Seafloor: IDOE Sediments on the Seafloor: IDOE Nazca Nazca Plate ProjectPlate Project

Surface sediment chemistry: total elemental ratios of cores,Surface sediment chemistry: total elemental ratios of cores,in this case, Fe/Al reveal the East Pacific Rise & Bauer Basinin this case, Fe/Al reveal the East Pacific Rise & Bauer Basin

McMurtry (1981)

Sediment Fe accumulation rates (mg/cmSediment Fe accumulation rates (mg/cm22101033 years) and years) and dissolved dissolved 33He midHe mid--depth water column anomalies along the EPRdepth water column anomalies along the EPR

McMurtry, unpubl. data

Surface (0Surface (0--5 cm) distribution of Fe5 cm) distribution of Fe--montmorillonitemontmorilloniteand and 33He water column anomalies along the EPRHe water column anomalies along the EPR

McMurtry, unpubl. data

Surface sediment Surface sediment elemental maps ofelemental maps ofFe, Fe, Mn Mn and Niand Ni

Dymond et al., 1981

Surface sediment elemental maps ofSurface sediment elemental maps ofAl (Al (detritaldetrital) and ) and Si Si (biogenic) sources(biogenic) sources

from Dymond et al.,1981

Factor Analysis of Elemental ConcentrationsFactor Analysis of Elemental Concentrations

Factor loadings versus corelocations reveal distributionof three major Factors:

Factor 1 = hydrogenous (Ni, Al)Factor 2 = hydrothermal (Fe, Mn, Cu)Factor 3 = biogenic (Si)

Dymond et al., 1981

Model for Model for diagenetic diagenetic origin of Bauer Basin origin of Bauer Basin metalliferous metalliferous sediments: sediments: sedimemt sedimemt leach resultsleach results

Dymond et al., 1981

Model for Model for diagenetic diagenetic origin of Bauer Basin origin of Bauer Basin metalliferous metalliferous sediments: bottom current directionssediments: bottom current directions

Dymond et al., 1981

Model for Model for diagenetic diagenetic origin of Bauer Basin origin of Bauer Basin

metalliferous metalliferous sediments: sediments:

SEM evidence for SEM evidence for diatom alteration to diatom alteration to

claysclays

Dymond et al., 1981

Model for Model for diagenetic diagenetic origin of Bauer Basin origin of Bauer Basin metalliferous metalliferous sediments: Fesediments: Fe--MnMn--SiSi

Dymond et al., 1981

East Pacific Rise & Bauer Basin East Pacific Rise & Bauer Basin Clay Mineral GenesisClay Mineral Genesis

McMurtry & Yeh (1981)

XX--ray Diffraction Patterns, <2 ray Diffraction Patterns, <2 μμm, carbonate m, carbonate & Fe& Fe--oxide free basisoxide free basis

McMurtry & Yeh (1981)

Effects of ethylene Effects of ethylene glycol treatment on glycol treatment on

smectitesmectite

dd--layer expansion =>layer expansion =>22--theta shifttheta shift

McMurtry & Yeh (1981)

Galapagos Mounds StudyGalapagos Mounds Study

McMurtry et al. (1983)

Galapagos Mounds Field DetailGalapagos Mounds Field Detail

McMurtry et al. (1983)

Models for Models for GenesisGenesis

Alvin photo of mounds Nontronite (dark green), Temp. inside = 30 C

Williams et al. (1979)

Alvin diving on Juan de Alvin diving on Juan de Fuca Fuca & & Gorda Gorda Ridges, 1984 NOAA Vents programRidges, 1984 NOAA Vents program

Geologic setting of Geologic setting of Axial Seamount, Axial Seamount,

Juan de Juan de Fuca Fuca RidgeRidge

Seabeam Seabeam & Side& Side--scan bathymetry, Axial Calderascan bathymetry, Axial Caldera

Ashes Vent Field

Alvin diving on Ashes vent fieldAlvin diving on Ashes vent field

Arquit (1986)

LowLow--T hydrothermal chimneys, Ashes vent T hydrothermal chimneys, Ashes vent field, Axial Calderafield, Axial Caldera

Alvin Push Core of Chimney, Dive 1411Alvin Push Core of Chimney, Dive 1411

TEM photos of TEM photos of hisingeritehisingerite, amorphous silica, , amorphous silica, nontronite nontronite (d), Axial Seamount(d), Axial Seamount

Archebacteria Archebacteria ((ArcheaArchea) ) in SEM, in SEM,

Loihi Loihi Seamount, Seamount,

HawaiiHawaii

Karl et al. (1983)

Topography of South Coast, Hawaii IslandTopography of South Coast, Hawaii Island

Courtesy of J. R. Smith

Early NOAA surveys, Early NOAA surveys, Loihi Loihi SeamountSeamount

Thousand Fingers vent field

Malahoff et al. (1982)

Methane Plumes, U. Tokyo Cruise, 1985Methane Plumes, U. Tokyo Cruise, 1985

Gamo et al. (1987)

LowLow--T Hydrothermal Deposit T Hydrothermal Deposit ZonationZonation, , LoihiLoihi

DeCarlo et al. (1983)

Comparative Metals, FeComparative Metals, Fe--Mont., Mont., NontronitesNontronites

DeCarlo et al. (1983)

HURL Pisces V HURL Pisces V diving: diving: Loihi Loihi

SeamountSeamount

Chimneys at edgeChimneys at edgeof West Pit Craterof West Pit Crater

HURL Pisces V HURL Pisces V diving:diving:

PelePele’’s s Vents, Vents, Loihi Loihi SeamountSeamount

PelePele’’s s Vents Chemistry: Vents Chemistry: SiSi--T relationsT relations

Sedwick et al. (1992)

PelePele’’s s Vents Chemistry: AnionsVents Chemistry: Anions

Sedwick et al. (1992)

PelePele’’s s Vents Chemistry: Alkali MetalsVents Chemistry: Alkali Metals

Sedwick et al. (1992)

PelePele’’s s Vents Chemistry: Alkaline EarthsVents Chemistry: Alkaline Earths

Sedwick et al. (1992)

PelePele’’s s Vents Chemistry: Transition MetalsVents Chemistry: Transition Metals

Sedwick et al. (1992)

PelePele’’s s Vents Chemistry Vents Chemistry -- ModelModel

Sedwick et al. (1992)

Hawaii Undersea Hawaii Undersea Research Observatory Research Observatory

(HUGO)(HUGO)

First Fiber Optic & First Fiber Optic & Power Cabled DeploymentPower Cabled Deploymentto an Active Underseato an Active UnderseaVolcano, 1998Volcano, 1998

⇒⇒ continuous realcontinuous real--time time monitoringmonitoring

Black Smokers & Massive SulfidesBlack Smokers & Massive Sulfides

Cover of Science Magazine,March, 1980F. N. Spiess et al.

Top of Chimney, Endeavor Ridge

Back to the Galapagos RiftBack to the Galapagos Rift

Seabeam Seabeam bathymetry, East Galapagos Riftbathymetry, East Galapagos Rift

Malahoff et al. (1983)

Geologic Setting of Geologic Setting of Massive Sulfides, Massive Sulfides,

Galapagos RiftGalapagos Rift

Malahoff et al. (1983)

Large Extinct Chimneys,Large Extinct Chimneys,Coalesced Chimney Coalesced Chimney

StacksStacks

Malahoff et al. (1983)

Size of the depositsSize of the deposits----Large!Large!

Malahoff et al. (1983)

Seafloor Alteration of Massive Seafloor Alteration of Massive SulfidesSulfides

Recycling at Convergent Recycling at Convergent Margins: the Margins: the Geostill Geostill HypothesisHypothesis

Mineral Mineral Zonation Zonation in the Andesin the Andes

Woollard & McMurtry (1979)

Major Hypotheses to Explain RegionalMajor Hypotheses to Explain RegionalZonationZonation

Woollard & McMurtry (1979)

Physical Properties Physical Properties of Major Metalsof Major Metals

Woollard & McMurtry (1979)

Melting Point of Melting Point of Major Metal Major Metal

SulfidesSulfides

Woollard & McMurtry (1979)

Range of equilibriumsolidus temperatures

Temperature of Vapor Temperature of Vapor Pressure of Metals Pressure of Metals

& Partial Pressure of & Partial Pressure of MetalMetal--ChloridesChlorides

Woollard & McMurtry (1979)

Ages of Major Geologic UnitsAges of Major Geologic Units

Woollard & McMurtry (1979)