Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2533
Relationships between protein-encoding gene abundance and corresponding process are commonly assumed yet rarely observed Relationships between protein-encoding gene abundance and corresponding process are commonly assumed yet rarely observed
For any enzyme-catalyzed reaction to occur, the corresponding protein-encoding genes and transcripts are necessary prerequisites. Thus, a positive relationship between the abundance of gene or transcripts and corresponding process rates is often assumed. To test this assumption, we conducted a meta-analysis of the relationships between gene and/or transcript abundances and corresponding...
Authors
Jennifer D. Rocca, Edward K. Hall, Jay T. Lennon, Sarah E. Evans, Mark P. Waldrop, James B. Cotner, Diana R. Nemergut, Emily B. Graham, Matthew D. Wallenstein
A 3400 year paleolimnological record of prehispanic human–environment interactions in the Holmul region of the southern Maya lowlands A 3400 year paleolimnological record of prehispanic human–environment interactions in the Holmul region of the southern Maya lowlands
The timing, magnitude and drivers of late Holocene environmental change in the Holmul region of the southern Maya lowlands are examined by combining paleoenvironmental and archeological data. Environmental proxy analyses on a ~ 3350 cal yr lacustrine sediment record include pollen, charcoal, loss on ignition, magnetic suscep- tibility, and elemental geochemistry. Archeological evidence...
Authors
David B. Wahl, Francisco Estrada-Belli, Lysanna Anderson
Stratigraphic reconnaissance of the Middle Jurassic Red Glacier Formation, Tuxedni Group, at Red Glacier, Cook Inlet, Alaska Stratigraphic reconnaissance of the Middle Jurassic Red Glacier Formation, Tuxedni Group, at Red Glacier, Cook Inlet, Alaska
The Alaska Division of Geological & Geophysical Surveys (DGGS) and U.S. Geological Survey (USGS) are implementing ongoing programs to characterize the petroleum potential of Cook Inlet basin. Since 2009 this program has included work on the Mesozoic stratigraphy of lower Cook Inlet, including the Middle Jurassic Tuxedni Group between Tuxedni and Iniskin bays (LePain and others, 2013...
Authors
David L. LePain, Richard G. Stanley
Structural superposition in fault systems bounding Santa Clara Valley, California Structural superposition in fault systems bounding Santa Clara Valley, California
Santa Clara Valley is bounded on the southwest and northeast by active strike-slip and reverse-oblique faults of the San Andreas fault system. On both sides of the valley, these faults are superposed on older normal and/or right-lateral normal oblique faults. The older faults comprised early components of the San Andreas fault system as it formed in the wake of the northward passage of...
Authors
Russell W. Graymer, Richard G. Stanley, David A. Ponce, Robert C. Jachens, Robert W. Simpson, Carl M. Wentworth
Truncorotalia crassaformis from its type locality: Comparison with Caribbean plankton and Pliocene relatives Truncorotalia crassaformis from its type locality: Comparison with Caribbean plankton and Pliocene relatives
Truncorotalia crassaformis has been identified in Pliocene-Holocene assemblages globally but there has been little analysis of specimens from its type locality at Lomita Quarry, California. This has led to confusion about some diagnostic criteria, particularly the presence of a peripheral keel. To better understand variation specimens are studied from the type locality (Pleistocene, c...
Authors
George H. Scott, James C. Ingle, Brendan McCane, Charles L. Powell, Robert C. Thunell
Evidence for outcrop-scale deformation band faults on Mars from Curiosity rover imagery Evidence for outcrop-scale deformation band faults on Mars from Curiosity rover imagery
No abstract available.
Authors
Jonathan S. Caine, Ryan B. Anderson, Kenneth E. Herkenhoff, Glynis M. Parrett
Magmatism, metasomatism, tectonism, and mineralization in the Humboldt Range, Pershing County, Nevada Magmatism, metasomatism, tectonism, and mineralization in the Humboldt Range, Pershing County, Nevada
Introduction The Humboldt Range, Pershing County, Nevada, predominantly consists of Mesozoic igneous and sedimentary rocks that were modified several times by magmatism, metasomatism, and tectonism, and contain a variety of metallic (Ag, Au, Pb, Zn, Sb, W, Hg) and non-metallic (dumortierite, pinite, fluorite) mineral deposits (Knopf, 1924; Kerr and Jenney, 1935; Kerr, 1938; Cameron, 1939
Authors
Peter G. Vikre
Lateritic, supergene rare earth element (REE) deposits Lateritic, supergene rare earth element (REE) deposits
Intensive lateritic weathering of bedrock under tropical or sub-tropical climatic conditions can form a variety of secondary, supergene-type deposits. These secondary deposits may range in composition from aluminous bauxites to iron and niobium, and include rare earth elements (REE). Over 250 lateritic deposits of REE are currently known and many have been important sources of REE. In...
Authors
Mark D. Cocker
The environmental and medical geochemistry of potentially hazardous materials produced by disasters The environmental and medical geochemistry of potentially hazardous materials produced by disasters
Many natural or human-caused disasters release potentially hazardous materials (HM) that may pose threats to the environment and health of exposed humans, wildlife, and livestock. This chapter summarizes the environmentally and toxicologically significant physical, mineralogical, and geochemical characteristics of materials produced by a wide variety of recent disasters, such as volcanic...
Authors
Geoffrey S. Plumlee, Suzette A. Morman, G.P. Meeker, Todd M. Hoefen, Philip L. Hageman, Ruth E. Wolf
Joint inversion of seismic and magnetotelluric data in the Parkfield Region of California using the normalized cross-gradient constraint Joint inversion of seismic and magnetotelluric data in the Parkfield Region of California using the normalized cross-gradient constraint
We present jointly inverted models of P-wave velocity (Vp) and electrical resistivity for a two-dimensional profile centered on the San Andreas Fault Observatory at Depth (SAFOD). Significant structural similarity between main features of the separately inverted Vp and resistivity models is exploited by carrying out a joint inversion of the two datasets using the normalized cross...
Authors
Ninfa L. Bennington, Haijiang Zhang, Cliff Thurber, Paul A. Bedrosian
Quaternary landscape development, alluvial fan chronology and erosion of the Mecca Hills at the southern end of the San Andreas Fault zone Quaternary landscape development, alluvial fan chronology and erosion of the Mecca Hills at the southern end of the San Andreas Fault zone
Quantitative geomorphic analysis combined with cosmogenic nuclide 10Be-based geochronology and denudation rates have been used to further the understanding of the Quaternary landscape development of the Mecca Hills, a zone of transpressional uplift along the southern end of the San Andreas Fault, in southern California. The similar timing of convergent uplifts along the San Andreas Fault...
Authors
Harrison J. Gray, Lewis A. Owen, Craig Dietsch, Richard A. Beck, Marc A. Caffee, Robert B. Finkelman, Shannon Mahan
Potash: a global overview of evaporate-related potash resources, including spatial databases of deposits, occurrences, and permissive tracts Potash: a global overview of evaporate-related potash resources, including spatial databases of deposits, occurrences, and permissive tracts
Potash is mined worldwide to provide potassium, an essential nutrient for food crops. Evaporite-hosted potash deposits are the largest source of salts that contain potassium in water-soluble form, including potassium chloride, potassium-magnesium chloride, potassium sulfate, and potassium nitrate. Thick sections of evaporitic salt that form laterally continuous strata in sedimentary...
Authors
Greta J. Orris, Mark D. Cocker, Pamela Dunlap, Jeff C. Wynn, Gregory T. Spanski, Deborah A. Briggs, Leila Gass, James D. Bliss, Karen S. Bolm, Chao Yang, Bruce R. Lipin, Stephen Ludington, Robert J. Miller, Miroslaw Slowakiewicz