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: 1962
Deep resistivity geophysics of the San Juan–Silverton caldera complex, San Juan County, Colorado (USA) Deep resistivity geophysics of the San Juan–Silverton caldera complex, San Juan County, Colorado (USA)
Magnetotelluric (MT) and audiomagnetotelluric (AMT) data are used to better understand the subsurface geology and mineral resources in the San Juan–Silverton caldera complex located near Silverton, Colorado, western United States, as part of the extensive southern Rocky Mountains volcanic field that covers much of southwestern Colorado and northern New Mexico. Seven MT and AMT profiles...
Authors
Brian D. Rodriguez, Douglas Yager, Eric D. Anderson, Robert L. Runkel, Bennett Eugene Hoogenboom, Bruce Smith, Maria Deszcz-Pan
Mesoproterozoic to Paleozoic tectonics, Pleistocene landforms, and Holocene seismicity in the Blue Ridge: Results from integrated studies of the 9 August 2020, Mw 5.1 earthquake area near Sparta, North Carolina, USA Mesoproterozoic to Paleozoic tectonics, Pleistocene landforms, and Holocene seismicity in the Blue Ridge: Results from integrated studies of the 9 August 2020, Mw 5.1 earthquake area near Sparta, North Carolina, USA
This field trip examines the results of integrated geologic studies of the 9 August 2020, Mw 5.1 earthquake near Sparta, North Carolina, USA. The earthquake generated ~4 km of coseismic surface rupture of the Little River fault and uplifted a surface area of ~11 km 2. The Little River fault is a thrust fault oriented 110–130°/45–70°SW, and mapped fault segments are en echelon with scarp...
Authors
Arthur J. Merschat, Mark W. Carter, Ashley S. Lynn, Kevin G. Stewart, Paula Figueiredo, William E. Odom, Ryan J. McAleer, Jorge A. Vazquez, Nicholas Edwin Powell, Christopher S. Holm-Denoma
Climate-driven increases in stream metal concentrations in mineralized watersheds throughout the Colorado Rocky Mountains, USA Climate-driven increases in stream metal concentrations in mineralized watersheds throughout the Colorado Rocky Mountains, USA
Increasing stream metal concentrations apparently caused by climate warming have been reported for a small number of mountain watersheds containing hydrothermally altered bedrock with abundant sulfide minerals (mineralized watersheds). Such increases are concerning and could negatively impact downstream ecosystem health, water resources, and mine-site remediation efforts. However, the
Authors
Andrew H. Manning, Tanya N. Petach, Robert L. Runkel, Diane M. McKnight
Evaluation of the characteristics, discharge, and water quality of selected springs at Fort Irwin National Training Center, San Bernardino County, California Evaluation of the characteristics, discharge, and water quality of selected springs at Fort Irwin National Training Center, San Bernardino County, California
Eight springs and seeps at Fort Irwin National Training Center were described and categorized by their general characteristics, discharge, geophysical properties, and water quality between 2015 and 2017. The data collected establish a modern (2017) baseline of hydrologic conditions at the springs. Two types of springs were identified: (1) precipitation-fed upland springs (Cave, Desert...
Authors
Jill N. Densmore, Drew C. Thayer, Meghan C. Dick, Peter W. Swarzenski, Lyndsay B. Ball, Celia Z. Rosecrans, Cordell Johnson
Paleogene sedimentary basin development in southern Nevada, USA Paleogene sedimentary basin development in southern Nevada, USA
The cause of the transition from Mesozoic and early Cenozoic crustal shortening to later extension in the western United States is debated. In many parts of the extant Sevier hinterland, now the Basin and Range Province, the sedimentary sections that provide the most direct record of that transition remain poorly studied and lack meaningful age control. In this paper, we present field
Authors
Jens-Erik Lundstern, Theresa Maude Schwartz, Cameron Mark Mercer, Joseph P. Colgan, Jeremiah B. Workman, Leah E. Morgan
Sulphide petrology and ore genesis of the stratabound Sheep Creek sediment-hosted Zn–Pb–Ag–Sn prospect, and U–Pb zircon constraints on the timing of magmatism in the northern Alaska Range Sulphide petrology and ore genesis of the stratabound Sheep Creek sediment-hosted Zn–Pb–Ag–Sn prospect, and U–Pb zircon constraints on the timing of magmatism in the northern Alaska Range
The Sheep Creek prospect is a stratabound Zn–Pb–Ag–Sn massive sulfide occurrence in the Bonnifield mining district, northern Alaska Range. The prospect is within a quartz–sericite–graphite–chlorite schist unit associated with Devonian carbonaceous and siliceous metasedimentary rocks. Volcanogenic massive sulfide (VMS) deposits in the district are hosted in felsic metavolcanic rocks (362...
Authors
Cynthia Dusel-Bacon, John N. Aleinikoff, Suzanne Paradise, John F. Slack
Trace silicon determination in biological samples by inductively coupled plasma mass spectrometry (ICP-MS): Insight into volatility of silicon species in hydrofluoric acid digests for optimal sample preparation and introduction to ICP-MS Trace silicon determination in biological samples by inductively coupled plasma mass spectrometry (ICP-MS): Insight into volatility of silicon species in hydrofluoric acid digests for optimal sample preparation and introduction to ICP-MS
A method for the determination of trace levels of silicon from biological materials by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. The volatility of water-soluble silicon species, hexafluorosilicic acid (H2SiF6), and sodium metasilicate (Na2SiO3) was investigated by evaporating respective solutions (50 µg/mL silicon) in nitric acid (HNO3), nitric acid +...
Authors
Zikri Arslan, Heather A. Lowers
Influence of inherited structure on flexural extension in foreland basin systems: Evidence from the northern Arkoma basin and southern Ozark dome, USA Influence of inherited structure on flexural extension in foreland basin systems: Evidence from the northern Arkoma basin and southern Ozark dome, USA
Extensional faults are key components of foreland basin systems. They form within the upper crust in response to flexure of the lithosphere and accommodate subsidence within the foredeep and forebulge depozones. Such faults are excellent proxies for orogenic system evolution and control the distribution of natural resources and hazards. However, the spatiotemporal evolution of flexural...
Authors
Brandon Michael Lutz, Mark R. Hudson, Tyson Michael Smith, Marieke Dechesne, Leland R. Spangler, Anne E. McCafferty, Chelsea Morgan Amaral, Neil Patrick Griffis, Jaime Ann Megumi Hirtz
Paleoproterozoic reworking of Archean crust and extreme back-arc metamorphism in the enigmatic southern Trans-Hudson orogen Paleoproterozoic reworking of Archean crust and extreme back-arc metamorphism in the enigmatic southern Trans-Hudson orogen
The crustal evolution of the southernmost ∼2000–1800 Ma Trans-Hudson orogen (THO) is enigmatic due to burial by Phanerozoic sediments. We provide new insights through petrochronologic analysis of a paragneiss drill core sample. Detrital zircon age peaks at 2625, 2340, and 1880 Ma and Hf isotopes suggest Paleoproterozoic arc development proximal to Archean source(s). Phase equilibria...
Authors
Ian William Hillenbrand, Amy K. Gilmer, Michael L. Williams, Amanda Kate Souders, Michael J. Jercinovic, Heather A. Lowers, Jorge A. Vazquez
Geoelectric evidence for a wide spatial footprint of active extension in central Colorado Geoelectric evidence for a wide spatial footprint of active extension in central Colorado
Three-dimensional magnetotelluric (MT) imaging in central Colorado reveals a set of north-striking high-conductivity tracks at lower-crustal (50–20 km) depths, with conductive finger-like structures rising off these tracks into the middle crust (20–5 km depth). We interpret these features to represent saline aqueous fluids and partial melt that are products of active extensional...
Authors
Benjamin S. Murphy, Jonathan Saul Caine, Paul A. Bedrosian, Kayla J Crosbie
Deep magmatic staging chambers for crustal layered mafic intrusions: An example from the Bushveld Complex of southern Africa Deep magmatic staging chambers for crustal layered mafic intrusions: An example from the Bushveld Complex of southern Africa
The deep mafic magmatic staging chambers of layered mafic intrusions have been conjectured but not imaged. Their existence has long been postulated from geochemical models which require multiple magma injections from staging chambers to account for their multi-scale igneous layering and variations in sources and degrees of crustal contamination. For the Bushveld Complex of southern...
Authors
Janine Cole, Carol A. Finn, Susan J. Webb
On-orbit calibration and performance of the EMIT imaging spectrometer On-orbit calibration and performance of the EMIT imaging spectrometer
The Earth surface Mineral dust source InvesTigation (EMIT) is a remote visible to shortwave infrared (VSWIR) imaging spectrometer that has been operating onboard the International Space Station since July 2022. This article describes EMIT's on-orbit spectroradiometric calibration and validation. Accurate spectroscopy is vital to achieve consistent mapping results with orbital imaging...
Authors
David R. Thompson, Robert O. Green, Christine Bradley, Philip G. Brodrick, Natalie Mahowald, Eyal Ben-Dor, Matthew R. Bennett, Michael Bernas, Nimrod Carmon, K. Dana Chadwick, Roger N. Clark, Red Willow Coleman, Evan Cox, Ernesto L. Diaz, Michael L. Eastwood, Regina Eckert, Bethany L. Ehlmann, Paul Ginoux, Marıa Goncalves Ageitos, Kathleen Grant, Louis Guanter, Daniela Heller Pearlshtien, Mark Helmlinger, Harrison Herzog, Todd M. Hoefen, Yue Huang, Abigail Keebler, Olga Kalashnikova, Didier Keymeulen, Raymond F. Kokaly, Martina Klose, Longlei Li, Sarah Lundeen, John Michael Meyer, Elizabeth Middleton, Ron L. Miller, Pantazis Mouroulis, Bogdan Oaida, Vicenzo Obiso, Francisco Ochoa, Winston Olson-Duvall, Gregory S. Okin, Thomas H. Painter, Carlos Perez Garcıa-Pando, Randy Pollock, Vincent J. Realmuto, Lucas Shaw, Peter Sullivan, Gregg A. Swayze, Erik Thingvold, Andrew K Thorpe, Suresh Vannan, Catalina Villarreal, Charlene Ung, Daniel W. Wilson, Sander Zandbergen