Publications
Products (journal articles, reports, fact sheets) authored by current and past scientists are listed below. Please check the USGS Pubs Warehouse for other USGS publications.
Filter Total Items: 1986
Sulfur geochemistry and microbial sulfate reduction during low-temperature alteration of uplifted lower oceanic crust: Insights from ODP Hole 735B Sulfur geochemistry and microbial sulfate reduction during low-temperature alteration of uplifted lower oceanic crust: Insights from ODP Hole 735B
Sulfide petrography plus whole rock contents and isotope ratios of sulfur were measured in a 1.5 km section of oceanic gabbros in order to understand the geochemistry of sulfur cycling during low-temperature seawater alteration of the lower oceanic crust, and to test whether microbial effects may be present. Most samples have low SO4/ΣS values (≤ 0.15), have retained igneous globules of...
Authors
Susan E. Alford, Jeffrey C. Alt, Wayne C. Shanks
Spatial mapping of mineralization with manganese-enhanced magnetic resonance imaging Spatial mapping of mineralization with manganese-enhanced magnetic resonance imaging
Paramagnetic manganese can be employed as a calcium surrogate to sensitize the magnetic resonance imaging (MRI) technique to the processing of calcium during the bone formation process. At low doses, after just 48h of exposure, osteoblasts take up sufficient quantities of manganese to cause marked reductions in the water proton T1 values compared with untreated cells. After just 24h of...
Authors
I.E. Chesnick, J.A. Centeno, T.I. Todorov, A.E. Koenig, K. Potter
Evidence for low-grade metamorphism, hydrothermal alteration, and diagenesis on Mars from phyllosilicate mineral assemblages Evidence for low-grade metamorphism, hydrothermal alteration, and diagenesis on Mars from phyllosilicate mineral assemblages
The enhanced spatial and spectral resolution provided by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on the Mars Reconnaissance Orbiter (MRO) has led to the discovery of numerous hydrated silicate minerals on Mars, particularly in the ancient, cratered crust comprising the southern highlands. Phases recently identified using visible/near-infrared spectra include...
Authors
Bethany L. Ehlmann, John F Mustard, Roger N. Clark, Gregg A. Swayze, Scott L. Murchie
Exhumation history of the NW Indian Himalaya revealed by fission track and 40Ar/39Ar ages Exhumation history of the NW Indian Himalaya revealed by fission track and 40Ar/39Ar ages
New fission track and Ar/Ar geochronological data provide time constraints on the exhumation history of the Himalayan nappes in the Mandi (Beas valley) — Tso Morari transect of the NW Indian Himalaya. Results from this and previous studies suggest that the SW-directed North Himalayan nappes were emplaced by detachment from the underthrusted upper Indian crust by 55 Ma and metamorphosed...
Authors
Micha Schlup, Albrecht Steck, Andrew Carter, Michael Cosca, Jean-Luc Epard, Johannes Hunziker
Impact of mine and natural sources of mercury on water, sediment, and biota in Harley Gulch adjacent to the Abbott-Turkey Run mine, Lake County, California Impact of mine and natural sources of mercury on water, sediment, and biota in Harley Gulch adjacent to the Abbott-Turkey Run mine, Lake County, California
Executive Summary Stable-isotope data indicate that there are three sources of water that effect the composition and Hg concentration of waters in Harley Gulch: (1) meteoric water that dominates water chemistry during the wet season; (2) thermal water effluent from the Turkey Run mine that effects the chemistry at sample site HG1; and (3) cold connate groundwater that dominates water...
Authors
James J. Rytuba, Roger L. Hothem, Brianne E. Brussee, Daniel N. Goldstein
And last comes XYZ And last comes XYZ
Catesian Coordinates can be used to specify the position of any point in three-dimensional space by measuring its distances from three mutually perpendicular planes.
Authors
Bill Langer
P is for pit P is for pit
A gravel pit that was a source of happy childhood memories showcases the evolution of mining technology.
Authors
W. H. Langer
R is for rocksicle R is for rocksicle
A Front Range perspective on managing and shipping aggregates.
Authors
W. H. Langer
N is for non-metallic N is for non-metallic
Annual non-metallic minerals are typically twice the value of metallic minerals, which takes a little of the sparkle out of gold.
Authors
W. H. Langer
O is for obsidian O is for obsidian
Although a relative youngster in geologic terms, obsidian can change over time from glass to mineral.
Authors
W. H. Langer
Distal signatures of Late Ordovician oceanic anoxia—New data from a classic epeiric ramp transect Distal signatures of Late Ordovician oceanic anoxia—New data from a classic epeiric ramp transect
No abstract available.
Authors
Patrick I. McLaughlin, Norlene Emerson, Brian Witzke, Bryan Sell, Poul Emsbo