Geology, Geophysics, and Geochemistry Science Center

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.

USGS Publications Warehouse

Filter Total Items: 1,632
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Year Published: 2021

Integrated geophysical imaging of rare-earth-element-bearing iron oxide-apatite deposits in the eastern Adirondack Highlands, New York

The eastern Adirondack Highlands of northern New York host dozens of iron oxide-apatite (IOA) deposits containing magnetite and rare earth element (REE)-bearing apatite. We use new aeromagnetic, aeroradiometric, ground gravity, and sample petrophysical and geochemical data to image and understand these deposits and their geologic framework....

Shah, Anjana K.; Taylor, Ryan D.; Walsh, Gregory; Phillips, Jeffrey

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Year Published: 2021

Quantifying model structural uncertainty using airborne electromagnetic data

The ability to quantify structural uncertainty in geological models that incorporate geophysical data is affected by two primary sources of uncertainty: geophysical parameter uncertainty and uncertainty in the relationship between geophysical parameters and geological properties of interest. Here, we introduce an open-source, trans-dimensional...

Minsley, Burke J.; Foks, N. Leon; Bedrosian, Paul A.

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Year Published: 2021

Interpreting and reporting 40Ar/39Ar geochronologic data

The 40Ar/39Ar dating method is among the most versatile of geochronometers, having the potential to date a broad variety of K-bearing materials spanning from the time of Earth’s formation into the historical realm. Measurements using modern noble-gas mass spectrometers are now producing 40Ar/39Ar dates with analytical uncertainties of ∼0.1%,...

Schaen, Allen J.; Jicha, Brian R.; Hodges, Kip V.; Vermeesch, Pieter; Stelten, Mark E.; Mercer, Cameron M.; Phillips, David; Rivera, Tiffany; Jourdan, Fred; Matchan, Erin L.; Hemming, Sidney R.; Morgan, Leah E.; Kelley, Simon P.; Cassata, William S.; Heizler, Matt T.; Vasconcelos, Paulo M.; Benowitz, Jeff A.; Koppers, Anthony A.P. ; Mark, Darren F.; Niespolo, Elizabeth M.; Courtney J. Sprain; Hames, William E.; Kuiper, Klaudia F.; Turrin, Brent D.; Renne, Paul R.; Ross, Jake; Nomade, Sebastian; Guillou, Hervé; Webb, Laura E.; Cohen, Barbara A.; Calvert, Andrew T.; Joyce, Nancy; Ganderød, Morgan; Wijbrans, Jan; Ishizuka, Osamu; He, Huaiyu; Ramirez, Adán; Pfänder, Jörg; Lopez-Martínez, Margarita; Qiu, Huaning; Singer, Brad S.

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Year Published: 2021

Two-event genesis of Butte lode veins: Geologic and geochronologic evidence from ore veins, dikes, and host plutons

The long-standing ore-genesis model for world-class deposits of the Butte mining district, Montana, is of deep pre-Main Stage porphyry Cu-Mo and overlying Main Stage Ag-Zn-Cu-zoned lode veinsformed from discrete hydrothermal systems related to rhyolite dikes. The lode-specific model describes metals zones that formed in the lode veins as...

Lund, Karen; McAleer, Ryan J.; Aleinikoff, John N.; Cosca, Michael

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Year Published: 2021

Model structural uncertainty quantification and hydrogeophysical data integration using airborne electromagnetic data

Airborne electromagnetic (AEM) dataare usedto estimate large-scale model structural geometry, i.e. the spatial distribution of different lithological units based on assumed or estimated resistivity-lithology relationships, and the uncertainty in those structures given imperfect measurements. Geophysically derived estimates of model structural...

Minsley, Burke J.; Christensen, Nikolaj K; Christensen, Steen; Ley-Cooper, Yusen

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Year Published: 2020

Systems-deposits-commodities-critical minerals table for the earth mapping resources initiative

To define and prioritize focus areas across the United States with resource potential for 35 critical minerals in a few years’ time, the U.S Geological Survey Earth Mapping Resources Initiative (Earth MRI) required an efficient approach to streamline workflow. A mineral systems approach based on current understanding of how ore deposits that...

Hofstra, Albert H.; Kreiner, Douglas C.
Hofstra, A.H., and Kreiner, D.C., 2020, Systems-Deposits-Commodities-Critical Minerals Table for the Earth Mapping Resources Initiative (ver. 1.1, May 2021): U.S. Geological Survey Open-File Report 2020–1042, 26 p., https://doi.org/10.3133/ofr20201042.

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Year Published: 2020

DGMETA (version 1)—Dissolved gas modeling and environmental tracer analysis computer program

DGMETA (Dissolved Gas Modeling and Environmental Tracer Analysis) is a Microsoft Excel-based computer program that is used for modeling air-water equilibrium conditions from measurements of dissolved gases and for computing concentrations of environmental tracers that rely on air-water equilibrium model results. DGMETA can solve for the...

Jurgens, Bryant C.; Böhlke, J.K.; Haase, Karl; Busenberg, Eurybiades; Hunt, Andrew G.; Hansen, Jeffrey A.
Jurgens, B.C., Böhlke, J., Haase, K., Busenberg, E., Hunt, A.G., and Hansen, J.A., 2020, DGMETA (version 1)—Dissolved gas modeling and environmental tracer analysis computer program: U.S. Geological Survey Techniques and Methods 4-F5, 50 p., https://doi.org/10.3133/tm4F5.

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Year Published: 2020

Cretaceous to Oligocene magmatic and tectonic evolution of the western Alaska Range: insights from U-Pb and 40Ar/39Ar geochronology

New U-Pb and 40Ar/39Ar ages integrated with geologic mapping and observations across the western Alaska Range constrain the distribution and tectonic setting of Cretaceous to Oligocene magmatism along an evolving accretionary plate margin in south-central Alaska. These rocks were emplaced across basement domains that include Neoproterozoic to...

Jones, James V.; Todd, Erin; Box, Stephen E.; Haeussler, Peter; Holm-Denoma, Christopher S.; Karl, Susan M.; Graham, Garth E.; Bradley, Dwight C.; Kylander-Clark, Andrew R.C.; Friedman, Richard M.; Layer, Paul W.

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Year Published: 2020

Baseflow age distributions and depth of active groundwater flow in a snow‐dominated mountain headwater basin

Deeper flows through bedrock in mountain watersheds could be important, but lack of data to characterize bedrock properties limits understanding. To address data scarcity, we combine a previously published integrated hydrologic model of a snow‐dominated, headwater basin of the Colorado River with a new method for dating baseflow age using...

Carroll, Rosemary W.H.; Manning, Andrew H.; Niswonger, Richard G.; Marchetti, David W; Williams, Kenneth H.

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Year Published: 2020

Alkalic-type epithermal gold deposit model; Chapter R in Mineral deposit models for resource assessment

This report summarizes the primary characteristics of alkalic-type epithermal gold (Au) deposits and provides an updated descriptive model. These deposits, primarily of Mesozoic to Neogene age, are among the largest epithermal gold deposits in the world. Considered a subset of low-sulfidation epithermal deposits, they are spatially and genetically...

Kelley, Karen D.; Spry, Paul G.; McLemore, Virginia T.; Fey, David L.; Anderson, Eric D.
Kelley, K.D., Spry, P.G., McLemore, V.T., Fey, D.L., and Anderson, E.D., 2020, Alkalic-type epithermal gold deposit model: U.S. Geological Survey Scientific Investigations Report 2010–5070–R, 74 p., https://doi.org/ 10.3133/ sir20105070R.

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Year Published: 2020

Assessing uranium and select trace elements associated with breccia pipe uranium deposits in the Colorado River and main tributaries in Grand Canyon, USA

Assessing chemical loading from streams in remote, difficult-to-access watersheds is challenging. The Grand Canyon area in northern Arizona, an international tourist destination and sacred place for many Native Americans, is characterized by broad plateaus divided by canyons as much as two-thousand meters deep and hosts some of the highest-grade...

Tillman, Fred; Anderson, Jessica; Unema, Joel; Chapin, Thomas
Tillman, F.D, Anderson, J.R., Unema, J.A., and Chapin, T.P., 2020, Assessing uranium and select trace elements associated with breccia pipe uranium deposits in the Colorado River and main tributaries in Grand Canyon, USA. PLoS ONE, 15(11): e0241502.

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Year Published: 2020

Cenozoic tectonic evolution of the Ecemiş fault zone and adjacent basins, central Anatolia, Turkey during the transition from Arabia - Eurasia collision to escape tectonics

The effects of Arabia-Eurasia collision are recorded in faults, basins, and exhumed metamorphic massifs across eastern and central Anatolia. These faults and basins also preserve evidence of major changes in deformation and associated sedimentary processes along major suture zones including the Inner Tauride suture where it lies along the southern...

Umhoefer, Paul J.; Thompson, Stuart; Lefebre, Come; Cosca, Michael; Teyssier, Christian; Whitney, Donna L.