James Hein
zation
Geologist Emeritus with the USGS Pacific Coastal and Marine Science Center
Science and Products
Filter Total Items: 167
Ferromanganese crusts as indicators for paleoceanographic events in the NE Atlantic Ferromanganese crusts as indicators for paleoceanographic events in the NE Atlantic
Hydrogenetic ferromanganese crusts reflect the chemical conditions of the sewater from which they formed. Fine-scale geochemical analysis of crust layers in combination with age determinations can therefore be used to investigate paleoceanographic changes which are recorded in geochemical gradients in the crusts. At Tropic seamount (off northwest Africa), uniform crust growth influenced...
Authors
A. Koschinsky, P. Halbach, J.R. Hein, A. Mangini
238U-234U-230Th chronometry of Fe-Mn crusts: Growth processes and recovery of thorium isotopic ratios of seawater 238U-234U-230Th chronometry of Fe-Mn crusts: Growth processes and recovery of thorium isotopic ratios of seawater
Comparison of (234U) excess⁄(238U) and (230Th⁄232Th) activity ratios in oceanic Fe-Mn deposits provides a method for assessing the closed-system behaviour of 238U-234U-230Th, as well as variations in the initial uranium and thorium isotopic ratios of the precipitated metal oxides. This approach is illustrated using a Fe-Mn crust from Lotab seamount (Marshall Islands, west equatorial...
Authors
F. Chabaux, A.S. Cohen, R. K. O’Nions, J.R. Hein
Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California
Compositions of lavas from seven small to medium-sized seamounts, between lat 34.0°N and 30.5°N offshore southern and Baja California, include low-K2O tholeiitic, transitional, and mildly to moderately alkalic basalt and their differentiates. The low-K2O tholeiites resemble primitive (>9% MgO) mid-oceanic-ridge basalt (MORB) with low incompatible element abundances and very depleted...
Authors
A. S. Davis, S.H. Gunn, W.A. Bohrson, L.-B. Gray, J.R. Hein
Diagenesis of diatomite from the Kolubara Coal Basin, Baroševac, Serbia Diagenesis of diatomite from the Kolubara Coal Basin, Baroševac, Serbia
Diatomite associated with the Kolubara Coal Basin was studied to better understand early stage silica diagenesis of shallow water deposits. The Kolubara Basin consists of Neogene siliciclastic rocks, diatomite, marlstone and rare carbonates. Palaeozoic metamorphic and Mesozoic sedimentary and igneous basement rocks are transgressively overlain by Upper Miocene sandstone, siltstone, shale...
Authors
J. Obradovic, James R. Hein, J. Djurdjevic
Data and results from R.V. Aleksandr Vinogradov cruises 91-AV-19/1, North Pacific hydrochemistry transect; 91-AV-19/2, North Equatorial Pacific Karin Ridge Fe-Mn crust studies; and 91-AV-19/4, Northwest Pacific and Bering Sea sediment geochemistry and pal Data and results from R.V. Aleksandr Vinogradov cruises 91-AV-19/1, North Pacific hydrochemistry transect; 91-AV-19/2, North Equatorial Pacific Karin Ridge Fe-Mn crust studies; and 91-AV-19/4, Northwest Pacific and Bering Sea sediment geochemistry and pal
No abstract available.
Authors
A.S. Bychkov, A. E. Gibbs
Composition and origin of hydrothermal ironstones from central Pacific seamounts Composition and origin of hydrothermal ironstones from central Pacific seamounts
Ironstones recovered from five Late Cretaceous seamounts in the central Pacific region probably formed during late-stage edifice-building volcanism. Ironstones are dense and compact with the appearance of brown chert. The ironstones are characterized by a goethite mineralogy with FeOOH contents up to 88%, extreme fractionation of Fe and Mn, low trace-element and rare earth element...
Authors
J.R. Hein, Y. Hsueh-Wen, S.H. Gunn, A. E. Gibbs, W. Chung-ho
Two major Cenozoic episodes of phosphogenesis recorded in equatorial Pacific seamount deposits Two major Cenozoic episodes of phosphogenesis recorded in equatorial Pacific seamount deposits
Seamount phosphorites have been recognized since the 1950s, but this is the first study to provide an in depth exploration of the origin and history of these widespread deposits. Representative samples from equatorial Pacific Cretaceous seamounts were analyzed for chemical, mineralogical, and stable isotope compositions. The phosphorites occur in a wide variety of forms, but most...
Authors
J.R. Hein, Yeh Hsueh-Wen, S.H. Gunn, W.V. Sliter, L.M. Benninger, Wang Chung-Ho
Hydrothermal palygorskite and ferromanganese mineralization at a central California margin fracture zone Hydrothermal palygorskite and ferromanganese mineralization at a central California margin fracture zone
Ferromanganese oxyhydroxide crusts and nodules associated with palygorskite were recovered from the Santa Lucia Escarpment where the Morro Fracture Zone intersects the central California continental margin. Palygorskite was found in pure, high-Mg, low-Al, boxwork-textured veins, and disseminated in poorly consolidated palygorskite-rich mudstone. The purity of the palygorskite boxwork...
Authors
A. E. Gibbs, J.R. Hein, S.D. Lewis, D. S. McCulloch
Variations in the fine-scale composition of a central Pacific ferromanganese crust: Paleoceanographic implications Variations in the fine-scale composition of a central Pacific ferromanganese crust: Paleoceanographic implications
A 47- to 60-mm-thick Fe-Mn crust from Horizon Guyot (water depth 1800–1780 m), central Pacific, was used to evaluate the potential of crusts as recorders of Neogene paleoceanographic and paleoclimatic conditions. The chemical composition was determined by microprobe for 16 elements from a polished thin section. Three analyses were made per millimeter and averaged to give the composition...
Authors
J.R. Hein, W.A. Bohrson, M. S. Schulz, M. Noble, D.A. Clague
Geology, geophysics, geochemistry, and deep-sea mineral deposits, Federated States of Micronesia: KORDI-USGS R.V. Farnella Cruise F11-90-CP Geology, geophysics, geochemistry, and deep-sea mineral deposits, Federated States of Micronesia: KORDI-USGS R.V. Farnella Cruise F11-90-CP
No abstract available.
Authors
James R. Hein, Jung-Ho Ahn, J.C. Wong, Jung-Keuk Kang, V. K. Smith, Suk-Hoon Yoon, W. M. d’Angelo, Sang-Ok Yoo, A. E. Gibbs, Han-Joon Kim, P. J. Quinterno, Moon-Young Jung, A. S. Davis, Byong-Kwon Park, J.R. Gillison, M. S. Marlow, M. S. Schulz, D. F. Siems, J. E. Taggart, Norma Rait, L. G. Pickthorn, M.J. Malcolm, M. G. Kavulak, Hsueh-Wen Yeh, D. M. Mann, M.A. Noble, G. O. Riddle, B. H. Roushey, Hezekiah Smith
Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands
Six holes were drilled to depths of 30–69 m in the shallow lagoon of Aitutaki in the southern Cook Islands. One hole encountered pervasively dolomitized reef limestones at 36 m subbottom depth, which extended to the base of the drilled section at 69·3 m. This hole was drilled near the inner edge of the present barrier reef flat on the flank of a seismically defined subsurface ridge. Both...
Authors
James R. Hein, S.C. Gray, B. M. Richmond, L. D. White
Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history
Eustatic sea-level cycles superposed on thermal subsidence of an atoll produce layers of high sea-level reefs separated by erosional unconformities. Coral samples from these reefs from cores drilled to 50 m beneath the lagoons of Pukapuka and Rakahanga atolls, northern Cook Islands give electron spin resonance (ESR) and U-series ages ranging from the Holocene to 600,000 yr B.P. Subgroups...
Authors
S.C. Gray, J.R. Hein, R. Hausmann, U. Radtke
Science and Products
Filter Total Items: 167
Ferromanganese crusts as indicators for paleoceanographic events in the NE Atlantic Ferromanganese crusts as indicators for paleoceanographic events in the NE Atlantic
Hydrogenetic ferromanganese crusts reflect the chemical conditions of the sewater from which they formed. Fine-scale geochemical analysis of crust layers in combination with age determinations can therefore be used to investigate paleoceanographic changes which are recorded in geochemical gradients in the crusts. At Tropic seamount (off northwest Africa), uniform crust growth influenced...
Authors
A. Koschinsky, P. Halbach, J.R. Hein, A. Mangini
238U-234U-230Th chronometry of Fe-Mn crusts: Growth processes and recovery of thorium isotopic ratios of seawater 238U-234U-230Th chronometry of Fe-Mn crusts: Growth processes and recovery of thorium isotopic ratios of seawater
Comparison of (234U) excess⁄(238U) and (230Th⁄232Th) activity ratios in oceanic Fe-Mn deposits provides a method for assessing the closed-system behaviour of 238U-234U-230Th, as well as variations in the initial uranium and thorium isotopic ratios of the precipitated metal oxides. This approach is illustrated using a Fe-Mn crust from Lotab seamount (Marshall Islands, west equatorial...
Authors
F. Chabaux, A.S. Cohen, R. K. O’Nions, J.R. Hein
Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California
Compositions of lavas from seven small to medium-sized seamounts, between lat 34.0°N and 30.5°N offshore southern and Baja California, include low-K2O tholeiitic, transitional, and mildly to moderately alkalic basalt and their differentiates. The low-K2O tholeiites resemble primitive (>9% MgO) mid-oceanic-ridge basalt (MORB) with low incompatible element abundances and very depleted...
Authors
A. S. Davis, S.H. Gunn, W.A. Bohrson, L.-B. Gray, J.R. Hein
Diagenesis of diatomite from the Kolubara Coal Basin, Baroševac, Serbia Diagenesis of diatomite from the Kolubara Coal Basin, Baroševac, Serbia
Diatomite associated with the Kolubara Coal Basin was studied to better understand early stage silica diagenesis of shallow water deposits. The Kolubara Basin consists of Neogene siliciclastic rocks, diatomite, marlstone and rare carbonates. Palaeozoic metamorphic and Mesozoic sedimentary and igneous basement rocks are transgressively overlain by Upper Miocene sandstone, siltstone, shale...
Authors
J. Obradovic, James R. Hein, J. Djurdjevic
Data and results from R.V. Aleksandr Vinogradov cruises 91-AV-19/1, North Pacific hydrochemistry transect; 91-AV-19/2, North Equatorial Pacific Karin Ridge Fe-Mn crust studies; and 91-AV-19/4, Northwest Pacific and Bering Sea sediment geochemistry and pal Data and results from R.V. Aleksandr Vinogradov cruises 91-AV-19/1, North Pacific hydrochemistry transect; 91-AV-19/2, North Equatorial Pacific Karin Ridge Fe-Mn crust studies; and 91-AV-19/4, Northwest Pacific and Bering Sea sediment geochemistry and pal
No abstract available.
Authors
A.S. Bychkov, A. E. Gibbs
Composition and origin of hydrothermal ironstones from central Pacific seamounts Composition and origin of hydrothermal ironstones from central Pacific seamounts
Ironstones recovered from five Late Cretaceous seamounts in the central Pacific region probably formed during late-stage edifice-building volcanism. Ironstones are dense and compact with the appearance of brown chert. The ironstones are characterized by a goethite mineralogy with FeOOH contents up to 88%, extreme fractionation of Fe and Mn, low trace-element and rare earth element...
Authors
J.R. Hein, Y. Hsueh-Wen, S.H. Gunn, A. E. Gibbs, W. Chung-ho
Two major Cenozoic episodes of phosphogenesis recorded in equatorial Pacific seamount deposits Two major Cenozoic episodes of phosphogenesis recorded in equatorial Pacific seamount deposits
Seamount phosphorites have been recognized since the 1950s, but this is the first study to provide an in depth exploration of the origin and history of these widespread deposits. Representative samples from equatorial Pacific Cretaceous seamounts were analyzed for chemical, mineralogical, and stable isotope compositions. The phosphorites occur in a wide variety of forms, but most...
Authors
J.R. Hein, Yeh Hsueh-Wen, S.H. Gunn, W.V. Sliter, L.M. Benninger, Wang Chung-Ho
Hydrothermal palygorskite and ferromanganese mineralization at a central California margin fracture zone Hydrothermal palygorskite and ferromanganese mineralization at a central California margin fracture zone
Ferromanganese oxyhydroxide crusts and nodules associated with palygorskite were recovered from the Santa Lucia Escarpment where the Morro Fracture Zone intersects the central California continental margin. Palygorskite was found in pure, high-Mg, low-Al, boxwork-textured veins, and disseminated in poorly consolidated palygorskite-rich mudstone. The purity of the palygorskite boxwork...
Authors
A. E. Gibbs, J.R. Hein, S.D. Lewis, D. S. McCulloch
Variations in the fine-scale composition of a central Pacific ferromanganese crust: Paleoceanographic implications Variations in the fine-scale composition of a central Pacific ferromanganese crust: Paleoceanographic implications
A 47- to 60-mm-thick Fe-Mn crust from Horizon Guyot (water depth 1800–1780 m), central Pacific, was used to evaluate the potential of crusts as recorders of Neogene paleoceanographic and paleoclimatic conditions. The chemical composition was determined by microprobe for 16 elements from a polished thin section. Three analyses were made per millimeter and averaged to give the composition...
Authors
J.R. Hein, W.A. Bohrson, M. S. Schulz, M. Noble, D.A. Clague
Geology, geophysics, geochemistry, and deep-sea mineral deposits, Federated States of Micronesia: KORDI-USGS R.V. Farnella Cruise F11-90-CP Geology, geophysics, geochemistry, and deep-sea mineral deposits, Federated States of Micronesia: KORDI-USGS R.V. Farnella Cruise F11-90-CP
No abstract available.
Authors
James R. Hein, Jung-Ho Ahn, J.C. Wong, Jung-Keuk Kang, V. K. Smith, Suk-Hoon Yoon, W. M. d’Angelo, Sang-Ok Yoo, A. E. Gibbs, Han-Joon Kim, P. J. Quinterno, Moon-Young Jung, A. S. Davis, Byong-Kwon Park, J.R. Gillison, M. S. Marlow, M. S. Schulz, D. F. Siems, J. E. Taggart, Norma Rait, L. G. Pickthorn, M.J. Malcolm, M. G. Kavulak, Hsueh-Wen Yeh, D. M. Mann, M.A. Noble, G. O. Riddle, B. H. Roushey, Hezekiah Smith
Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands
Six holes were drilled to depths of 30–69 m in the shallow lagoon of Aitutaki in the southern Cook Islands. One hole encountered pervasively dolomitized reef limestones at 36 m subbottom depth, which extended to the base of the drilled section at 69·3 m. This hole was drilled near the inner edge of the present barrier reef flat on the flank of a seismically defined subsurface ridge. Both...
Authors
James R. Hein, S.C. Gray, B. M. Richmond, L. D. White
Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history
Eustatic sea-level cycles superposed on thermal subsidence of an atoll produce layers of high sea-level reefs separated by erosional unconformities. Coral samples from these reefs from cores drilled to 50 m beneath the lagoons of Pukapuka and Rakahanga atolls, northern Cook Islands give electron spin resonance (ESR) and U-series ages ranging from the Holocene to 600,000 yr B.P. Subgroups...
Authors
S.C. Gray, J.R. Hein, R. Hausmann, U. Radtke