James Hein
zation
Geologist Emeritus with the USGS Pacific Coastal and Marine Science Center
Science and Products
Copper-nickel-rich, amalgamated ferromanganese crust-nodule deposits from Shatsky Rise, NW Pacific
A unique set of ferromanganese crusts and nodules collected from Shatsky Rise (SR), NW Pacific, were analyzed for mineralogical and chemical compositions, and dated using Be isotopes and cobalt chronometry. The composition of these midlatitude, deep-water deposits is markedly different from northwest-equatorial Pacific (PCZ) crusts, where most studies have been conducted. Crusts and nodules on SR
The molecular mechanism of Mo isotope fractionation during adsorption to birnessite
Constraints on the development of Proterozoic basins in central India from 40Ar/39Ar analysis of authigenic glauconitic minerals
Seamounts and ferromanganese crusts within and near the U.S. EEZ off California - Data for RV Farnella cruise F7-87-SC
Ferromanganese crusts as archives of deep water Cd isotope compositions
Seamount mineral deposits: A source of rare metals for high technology industries
Early Pleistocene origin of reefs around Lanai, Hawaii
Spotlight 6: Davidson seamount
Genesis of a regionally widespread celadonitic chert ironstone bed overlying upper Lias manganese deposits, Hungary
Thallium isotope evidence for a permanent increase in marine organic carbon export in the early Eocene
Coral reef evolution on rapidly subsiding margins
Seamount characteristics and mine-site model applied to exploration- and mining-lease-block selection for cobalt-rich ferromanganese crusts
Science and Products
- Science
- Data
- Maps
- Multimedia
- Publications
Filter Total Items: 167
Copper-nickel-rich, amalgamated ferromanganese crust-nodule deposits from Shatsky Rise, NW Pacific
A unique set of ferromanganese crusts and nodules collected from Shatsky Rise (SR), NW Pacific, were analyzed for mineralogical and chemical compositions, and dated using Be isotopes and cobalt chronometry. The composition of these midlatitude, deep-water deposits is markedly different from northwest-equatorial Pacific (PCZ) crusts, where most studies have been conducted. Crusts and nodules on SR
AuthorsJ. R. Hein, T.A. Conrad, M. Frank, M. Christl, W.W. SagerThe molecular mechanism of Mo isotope fractionation during adsorption to birnessite
Fractionation of Mo isotopes during adsorption to manganese oxides is a primary control on the global ocean Mo isotope budget. Previous attempts to explain what drives the surprisingly large isotope effect δ97/95Modissolved-δ97/95Moadsorbed=1.8‰ have not successfully resolved the fractionation mechanism. New evidence from extended X-ray absorption fine structure analysis and density functional theAuthorsL.E. Wasylenki, C.L. Weeks, J.R. Bargar, T.G. Spiro, J. R. Hein, A.D. AnbarConstraints on the development of Proterozoic basins in central India from 40Ar/39Ar analysis of authigenic glauconitic minerals
Ages of some key stratigraphic sequences in central Indian Proterozoic basins are based predominantly on lithostratigraphic relationships that have been constrained by only a few radioisotopic dates. To help improve age constraints, single grains of glauconitic minerals taken from sandstone and limestone in two Proterozoic sequences in the Pranhita-Godavari Valley and the Chattisgarh basin were anAuthorsJ. E. Conrad, J. R. Hein, A.K. Chaudhuri, S. Patranabis-Deb, J. Mukhopadhyay, G.K. Deb, N.J. BeukesSeamounts and ferromanganese crusts within and near the U.S. EEZ off California - Data for RV Farnella cruise F7-87-SC
The purpose of this report is to present and briefly describe ship-board and laboratory data for a U.S. Geological Survey (USGS) research cruise aboard the RV Farnella that took place December 3-21, 1987 (cruise F7-87-SC). The purpose of the cruise was to survey seamounts and ferromanganese crusts within and near the U.S. Exclusive Economic Zone (EEZ) off California. Eight seamounts were studied -AuthorsJames R. Hein, Jane A. Reid, Tracey A. Conrad, Rachel E. Dunham, David A. Clague, Marjorie S. Schulz, Alice S. DavisFerromanganese crusts as archives of deep water Cd isotope compositions
The geochemistry of Cd in seawater has attracted significant attention owing to the nutrient-like properties of this element. Recent culturing studies have demonstrated that Cd is a biologically important trace metal that plays a role in the sequestration of inorganic carbon. This conclusion is supported by recent isotope data for Cd dissolved in seawater and incorporated in cultured phytoplanktonAuthorsT. J. Horner, M. Schönbächler, M. Rehkämper, S.G. Nielsen, H. Williams, A. N. Halliday, Z. Xue, James R. HeinSeamount mineral deposits: A source of rare metals for high technology industries
The near exponential growth in Earth’s population and the global economy puts increasing constraints on our planet’s finite supply of natural metal resources, and, consequently, there is an increasing need for new sources to supply high-tech industries. To date, effectively all of our raw-metal resources are produced at land-based sites. Except for nearshore placer deposits, the marine environmenAuthorsJames R. Hein, Tracey A. Conrad, Hubert StaudigelEarly Pleistocene origin of reefs around Lanai, Hawaii
A sequence of submerged terraces (L1–L12) offshore Lanai was previously interpreted as reefal, and correlated with a similar series of reef terraces offshore Hawaii island, whose ages are known to be <500 ka. We present bathymetric, observational, lithologic and 51 87Sr/86Sr isotopic measurements for the submerged Lanai terraces ranging from −300 to −1000 m (L3–L12) that indicate that these terracAuthorsJody M. Webster, David A. Clague, Iain D.E. Faichney, Paul D. Fullagar, James R. Hein, James G. Moore, Charles K. PaullSpotlight 6: Davidson seamount
Davidson Seamount is located about 80 km off the central California coast in the Monterey Bay National Marine Sanctuary. It is one of the better-explored seamounts in the world, having been sampled and observed during 32 dives by the remotely operated vehicle (ROV) Tiburon. These dives mapped the bottom substrate and biological communities, and collected over 280 rock samples and nearly as many beAuthorsDavid A. Clague, L. Lundsten, James R. Hein, Jennifer B. Paduan, Alice DavisGenesis of a regionally widespread celadonitic chert ironstone bed overlying upper Lias manganese deposits, Hungary
Mineralogy and chemical composition are presented for a chert-ironstone bed that overlies the ??rk??t Mn deposit. This bed is mottled green-brown in its lower and upper parts, which are composed of quartz, goethite and celadonite. These parts of the bed are interpreted to be strongly altered tuffs, reflecting oxidic, low-temperature alteration of a hydrated, Fe-rich, Al-poor tuff, and K and Mg uptAuthorsMarta Polgari, J. R. Hein, M. Toth, A. Brukner-Wein, T. Vigh, L. Biro, C. CserhatiThallium isotope evidence for a permanent increase in marine organic carbon export in the early Eocene
The first high resolution thallium (Tl) isotope records in two ferromanganese crusts (Fe-Mn crusts), CD29 and D11 from the Pacific Ocean are presented. The crusts record pronounced but systematic changes in 205Tl/203Tl that are unlikely to reflect diagenetic overprinting or changes in isotope fractionation between seawater and Fe-Mn crusts. It appears more likely that the Fe-Mn crusts track the TlAuthorsS.G. Nielsen, S. Mar-Gerrison, A. Gannoun, D. LaRowe, V. Klemm, A. N. Halliday, K.W. Burton, J. R. HeinCoral reef evolution on rapidly subsiding margins
A series of well-developed submerged coral reefs are preserved in the Huon Gulf (Papua New Guinea) and around Hawaii. Despite different tectonics settings, both regions have experienced rapid subsidence (2-6??m/ka) over the last 500??ka. Rapid subsidence, combined with eustatic sea-level changes, is responsible for repeated drowning and backstepping of coral reefs over this period. Because we canAuthorsJ.M. Webster, J.C. Braga, D. A. Clague, C. Gallup, J. R. Hein, D.C. Potts, W. Renema, R. Riding, K. Riker-Coleman, E. Silver, L.M. WallaceSeamount characteristics and mine-site model applied to exploration- and mining-lease-block selection for cobalt-rich ferromanganese crusts
Regulations are being developed through the International Seabed Authority (ISBA) for the exploration and mining of cobalt-rich ferromanganese crusts. This paper lays out geologic and geomorphologic criteria that can be used to determine the size and number of exploration and mine-site blocks that will be the focus of much discussion within the ISBA Council deliberations. The surface areas of 155AuthorsJames R. Hein, Tracey A. Conrad, Rachel E. Dunham - News