Publications
Filter Total Items: 1492
Iron-sulfur-carbon relationships in organic-carbon-rich sequences I: Cretaceous Western Interior seaway Iron-sulfur-carbon relationships in organic-carbon-rich sequences I: Cretaceous Western Interior seaway
No abstract available.
Authors
Walter E. Dean, Michael A. Arthur
Borax in the supraglacial moraine of the Lewis Cliff, Buckley Island quadrangle--first Antarctic occurrence Borax in the supraglacial moraine of the Lewis Cliff, Buckley Island quadrangle--first Antarctic occurrence
During the 1987-1988 austral summer field season, membersof the south party of the antarctic search for meteorites south-ern team* working in the Lewis Cliff/Colbert Hills region dis-covered several areas of unusual mineralization within theLewis Cliff ice tongue and its associated moraine field (figure1). The Lewis Cliff ice tongue (84°15'S 161°25'E) is a meteorite-stranding surface of...
Authors
J. J. Fitzpatrick, D.R. Muhs
Uranium-series ages, faunal correlations and tectonic deformation of marine terraces within the Agua Blanca fault zone at Punta Banda, northern Baja California, Mexico Uranium-series ages, faunal correlations and tectonic deformation of marine terraces within the Agua Blanca fault zone at Punta Banda, northern Baja California, Mexico
No abstract available.
Authors
T. K. Rockwell, D.R. Muhs, G. L. Kennedy, M.E. Hatch, S.M. Wilson, R.E. Klinger
Morphology of Red Creek, Wyoming, an arid-region anastomosing channel system Morphology of Red Creek, Wyoming, an arid-region anastomosing channel system
The narrow, deep, and sinuous main channel is flanked by anastomosing flood channels, or anabranches. Most anabranches are initiated at meander bends. The primary mechanism of anabranch initiation is avulsion during overbank floods. -from Author
Authors
R.R. Schumann
Geologic map of the Trident Peak SW quadrangle, Humboldt County, Nevada Geologic map of the Trident Peak SW quadrangle, Humboldt County, Nevada
No abstract available.
Authors
Scott A. Minor, Michael Wager, Craig S. Harwood
U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf systematics of Returned Mars Samples U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf systematics of Returned Mars Samples
No abstract available.
Authors
M. Tatsumoto, Wayne R. Premo
Stratigraphic evidence of Holocene faulting in the mid-continent: The Meers fault, southwestern Oklahoma Stratigraphic evidence of Holocene faulting in the mid-continent: The Meers fault, southwestern Oklahoma
Stratigraphic relations and ten 14C ages show that movement occurred on the Meers fault in late Holocene time. Movement on the fault postdates the Browns Creek Alluvium, which began to be deposited between 14,000 and 13,000 yr B.P., and predates the East Cache Alluvium, which was deposited between 800 and 100 yr B.P. Surface warping along the fault led to local stream incision on the...
Authors
Richard F. Madole
A paleomagnetic investigation of rocks from the Ohio Range and the Dry Valleys, Transantarctic Mountains, Antarctica A paleomagnetic investigation of rocks from the Ohio Range and the Dry Valleys, Transantarctic Mountains, Antarctica
Two well-defined virtual geomagnetic poles (VGPs) for East Antarctica were obtained from the Middle Jurassic Ferrar Dolerite, sampled from a thick sill on Mt Schopf in the Ohio Range, and from a horizontal sheet intruding Paleozoic granitic rocks at Mt Cerberus in the Dry Valleys. The VGP from the sill at Mt Schopf lies at lat. 58°.0S, long. 129°.0W (dm=13°, dp=12°), and the VGP from Mt...
Authors
Karl S. Kellogg
Sediment deposition in the Late Holocene abyssal Black Sea with climatic and chronological implications Sediment deposition in the Late Holocene abyssal Black Sea with climatic and chronological implications
The temporal sedimentary patterns in the Late Holocene central eastern and western Black Sea are very similar. The sedimentary history was most visibly affected by the coccolithophorid species Emiliania huxleyi which briefly invaded the Black Sea for the first time (“First Invasion Period”), nearly disappeared again shortly afterwards (“Transition Sapropel”), but returned permanently...
Authors
B.J. Hay, M.A. Arthur, Walter E. Dean, E.D. Neff, S. Honjo
Pyrite formation in the Lower Cretaceous Mowry Shale: Effect of organic matter type and reactive iron content Pyrite formation in the Lower Cretaceous Mowry Shale: Effect of organic matter type and reactive iron content
Geochemical analysis of the Lower Cretaceous Mowry Shale in Wyoming and Montana shows that organic matter type and reactive iron content limited pyrite formation during early diagenesis. Consequently, direct interpretation of paleosalinity cannot be made from a carbon/sulfur plot. Mowry Shale samples with hydrogen index (HI) less than 150 (mg hydrocarbon/ organic carbon) contain low...
Authors
Hugh R. Davis, Charles W. Byers, Walter E. Dean
Pedogenic replacement of aluminosilicate grains by CaCO3 in Ustollic Haplargids, south-central Montana, U.S.A. Pedogenic replacement of aluminosilicate grains by CaCO3 in Ustollic Haplargids, south-central Montana, U.S.A.
A chronosequence of calcic soils formed on granitic glaciofluvial terrace deposits of Rock Creek and the Clarks Fork in south-central Montana shows progressive replacement of aluminosilicate parent-material grains by calcium-magnesium carbonate. The terraces range from late Pliocene to Holocene in age as dated by tephrochronology, correlation, and stream incision rates. Replacement is...
Authors
Marith C. Reheis
Evolution of the Early Proterozoic Colorado province: Constraints from U-Pb geochronology Evolution of the Early Proterozoic Colorado province: Constraints from U-Pb geochronology
The Colorado province represents an addition of a belt of rocks more than 500 km wide to the southern margin of the Archean Wyoming craton during the Early Proterozoic, between about 1790 and 1660 Ma. Correspondence in ages between metamorphism, deformation, and plutonism; association of volcanic rocks with comagmatic calc-alkalic plutons; and lack of older basement are all consistent...
Authors
John C. Reed, M. E. Bickford, Wayne R. Premo, John N. Aleinikoff, John S. Pallister