Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

164811 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 26, results 626 - 650

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Model‐based decomposition of spatially varying temporal shifts in seasonal streamflow across north temperate US rivers.
Kevin M. Collins, Erin M. Schliep, Tyler Wagner, Christopher K. Wikle
2025, Water Resources Research (61)
Anthropogenically forced climate shifts disrupt the seasonal behavior of climatic and hydrologic processes. The seasonality of streamflow has significant implications for the ecology of riverine ecosystems and for meeting societal demands for water resources. We develop a hierarchical Bayesian model of daily streamflow to quantify how the...
Potential for hydroacoustic technology to describe physical habitat for imperilled native freshwater mussels
Jenny L. Hanson, Jayme Stone, Lisie Kitchel, Jesse Weinzinger, Teresa J. Newton
2025, Ecohydrology (18)
The lack of information on what constitutes suitable habitat for native freshwater mussels can limit restoration efforts. While many species reside in silt–sand–gravel substrates, species such as the Spectaclecase (Cumberlandia monodonta) and Salamander (Simpsonaias ambigua) mussels are thought to be associated with rock structures (e.g., wing dams...
The influence of nodule versus crust morphology on the composition of seamount-hosted ferromanganese minerals
Kira Mizell, Emily Piper, Terrence Blackburn, Amy Gartman
2025, Conference Paper
Ferromanganese mineral precipitation in the global oceans is ubiquitous, occurring in the form of both crusts and nodules at a broad range of depths and seafloor terrains. Although ferromanganese crusts and nodules are both composed of ferromanganese minerals, mineralogy and mean element concentrations compiled for regional crust versus nodule occurrences...
Fluid evolution and timing of the Stibnite-Yellow Pine district, Idaho
Mitchell M. Bennett, Erin E. Marsh, Heather A. Lowers
2025, Conference Paper
Gold, antimony, and tungsten resources of the Stibnite-Yellow Pine district, Idaho, are hosted in complexly faulted Late Cretaceous Atlanta Lobe of the Idaho batholith and surrounding Neoproterozoic-Paleozoic metamorphic rocks. This study utilizes detailed petrography and trace element chemistry of quartz to establish relative timing relationships between successive ore forming events...
Utilizing downhole datasets for modelling the aeromagnetic signature of the Iron Creek Co-Cu deposit in the Idaho Cobalt Belt
Daniel Schmidt, Geoffrey Phelps, Katharina I Pfaff, Thomas Monecke
2025, Conference Paper
The Idaho Cobalt Belt in east-central Idaho is host to some of the largest domestic Co resources, including the informal Iron Creek deposit. The two main ore zones of this deposit, the Iron Creek and the Ruby, are hosted in greenschist-grade interbedded argillite/siltstone and quartz-rich units of the Mesoproterozoic Apple...
Fingerprinting magmatic REE deposit sources with zircon petrochronology
Ian William Hillenbrand, Erin Kay Benson, Kathryn E. Watts, Jay Michael Thompson
2025, Conference Paper
Carbonatites and associated alkaline silicate rocks are of considerable economic interest due to their enrichments in rare earth elements. The petrogenesis and source(s) of these complexes, however, are poorly understood. Models propose either mantle plume-derived carbon-rich melts or a mantle source enriched by subduction-related metasomatism. We use zircon trace elements...
Geochemistry and thermometry of magnetite veins and replacements in iron ore deposits from the Iron Springs district, SW Utah, USA: Relation to magmatic and hydrothermal processes
Corey J. Meighan, Ryan D. Taylor, Albert H. Hofstra, Jay Michael Thompson
2025, Conference Paper
Ore-genesis, texture, chemical compositions, and thermometry of magnetite were used to better evaluate the origins of iron ore deposits across the Iron Spring district, Utah. Trace element compositions, determined by LA-ICP-MS, were used to calculate temperatures based on XMg numbers and characterize the trace element signatures of magmatic and hydrothermal...
Paleoproterozoic vein graphite mineralization caused by decarbonation in the Ruby Range, Montana, USA
George N.D. Case, Jay Michael Thompson, Sean P. Regan
2025, Conference Paper
Hydrothermal graphite veins are a possible source for modern battery materials and require better understanding of their carbon source(s) and absolute timing to develop mapable criteria for exploration models. We present new observations of graphite vein and alteration paragenesis and U-Pb LA-ICP-MS titanite age data from the Ruby prospect, Montana,...
Re-Os geochronology of molybdenite by LA-ICP-MS/MS
Amanda Souders, Jay Michael Thompson
2025, Conference Paper
Re-Os geochronology is a powerful tool to directly date sulphide mineralisation using phases such as molybdenite, pyrite and chalcopyrite. We present a snapshot of a method in development utilizing laser ablation inductively coupled-plasma ‘triple quad’ mass spectrometry (LA-ICP-MS/MS) for Re-Os geochronology of molybdenite. While traditional LA-(MC)-ICP-MS measurements are limited by...
40Ar/39Ar geochronology supporting mineral resources research at USGS Denver
Leah E. Morgan, Cameron Mark Mercer
2025, Conference Paper
The 40Ar/39Ar geochronology method is used to date potassium-bearing rocks and minerals, based on the decay of 40K to 40Ar, which provides important temporal constraints for geological events. The USGS Denver Argon Geochronology Laboratory dates samples from a variety of projects, mainly in the USGS Mineral Resource Program and the...
Seamless Geologic Map Database for the Intermountain West, United States: A foundational dataset for mineral systems analysis
Amy K. Gilmer, Kenzie J. Turner, Jeremiah B. Workman, Ren A. Thompson, Theresa Maude Schwartz, Chester A. Ruleman
2025, Conference Paper
The Intermountain West has a complex geologic history, resulting in the formation of a diverse array of mineral deposits.  Effective mineral exploration requires understanding the spatial and temporal relationships among geologic processes and events, a key focus of the mineral systems approach to exploration.  This paper presents the Intermountain West...
Ages and trace element fertility of porphyry-related mineralization in the Philipsburg polymetallic district, Montana, with a comparison to Butte
Celine M.E. Beaucamp, Christopher H. Gammons, Jay Michael Thompson, Holly J. Stein
2025, Conference Paper
The Philipsburg mining district is a Mo-Cu porphyry system with associated Cordilleran polymetallic veins. Geochronology was employed to date the porphyry (~66 Ma, U/Pb in zircon) and molybdenite mineralization from the veins (~76 Ma, Re-Os). Age results suggest that the two-mineralization events model proposed by Lund et al. (2018) for the...
Pre- and post-eruptive geochemical and isotopic fingerprints of rhyolites parental to volcano-sedimentary lithium brine and clay resources in the western USA & central Andes
Celestine N. Mercer, Regina Marie Khoury, Julie Roberge, Madison Myers
2025, Conference Paper
Lithium is a high-demand, critical element used not only in lightweight rechargeable lithium-ion batteries, but also in nuclear applications and industries producing ceramics, aluminum, and medical products. It is extracted primarily from pegmatites and volcano-sedimentary brines and clays in arid, closed lacustrine or caldera basins. Lithium brines of the central...
Water temperature regimes and thermal drivers in semi-natural and flow-regulated rivers of the northern Great Plains
Patrick Braaten, T. David Ritter, Tyler M. Haddix, David B. Fuller, John R. Hunziker, John G. Hargrave
2025, River Research and Applications (41) 2073-2091
Rivers of the northern Great Plains have lacked long-term, continuous water temperature assessments, and there is limited information on thermal regimes of these systems and factors driving water temperature. We collected and assembled 2001–2022 water temperature data from 18 sites on four reaches of three rivers that differ in anthropogenic...
Stable isotope composition and geochemistry of calcite and dolomite in the Mountain Pass carbonatite: A lens into petrogenesis
Erin Kay Benson, Kathryn E. Watts, Jay Michael Thompson, Heather A. Lowers
2025, Conference Paper
Carbonatites host most of the global rare earth element (REE) deposits. The petrogenesis of these rocks, including magmatic and post-magmatic processes, are poorly understood but critical in forming and upgrading these deposits. The Mountain Pass carbonatite, which hosts the only active REE mine in North America, is lithologically variable but...
Hyperspectral imaging of river bathymetry using an ensemble of regression trees
Carl J. Legleiter, Paul J. Kinzel, Brandon Overstreet, Lee R. Harrison
2025, Earth Surface Processes and Landforms (50)
Remote sensing has emerged as an effective tool for characterizing river systems, and machine learning (ML) techniques could make this approach even more powerful. To explore this possibility, we developed an ML-based workflow for hyperspectral imaging of river bathymetry using an ensemble of regression trees (HIRBERT). This approach involves using...
Scientific opportunities in the National Landscape Conservation System
Sarah K. Carter, Sarah E. Whipple, Samuel E. Jordan, Nicole M. Herman-Mercer, Robin C. Lewis, Karen L. Prentice, Zachary H. Bowen, Frederick L. Klasner
2025, Parks Stewardship Forum (41) 388-401
The National Landscape Conservation System consists of unique and beautiful places across America’s landscapes where identified resources and values are protected and science is highlighted. The mission of the National Landscape Conservation System (NLCS), which is managed by the Bureau of Land Management and is often referred to as the...
Evaluation of the acute toxicity of the piscicide TFM to Burbot
Nicholas Schloesser, James A. Luoma, Courtney Kirkeeng, Samantha L. Wolfe, Justin Schueller, Hannah Mann Thompson
2025, Journal of Wildlife Management (89)
Non-target animal sensitivity remains a concern when treating Laurentian Great Lakes streams with 4-nitro-3-(trifluoromethyl)phenol (TFM), the main pesticide used to control Sea Lamprey Petromyzon marinus as part of the bi-national Great Lakes Fishery Commission's Sea Lamprey Control Program. Populations of Burbot Lota lota, a historically and culturally important fish, inhabit some of the...
A soil velocity model for improved ground motion simulations in the U. S. Pacific Northwest
Alex R. Grant, Erin A. Wirth, Ian P. Stone
2025, Seismica (4)
Near-surface seismic velocity structure may significantly impact the intensity, duration, and frequency content of ground shaking during an earthquake. In this study, we compile 649 shear wave velocity (Vs) profiles throughout the U.S. Pacific Northwest and southern British Columbia (PNW) and use these measured profiles to develop a representative soil...
Decision support tools for brown pelican management in the northern Gulf of America (Gulf of Mexico)
James P. Cronin, Blair E. Tirpak, Leah L. Dale, Virginia L. Robenski, John M. Tirpak, Barry C. Wilson, William G. Vermillion, Donald R. Schoolmaster Jr.
2025, Journal of Wildlife Management (89)
Management plans with clear priorities can help to achieve brown pelican Pelecanus occidentalis conservation objectives in the northern Gulf of America (Gulf of Mexico). Efforts to establish clear priorities can be hindered by information gaps, especially those related to the uncertainty associated with changing conditions that influence brown pelican populations. We addressed...
Population structure and movement dynamics of Redband Trout in the Kootenai River basin
Courtnie L. Ghere, Malte Willmes, Ryan S. Hardy, Tyler J. Ross, James Dunnigan, Sean Wilson, Scott Carleton, Michael C. Quist
2025, River Research and Applications (41) 2218-2233
Redband Trout Oncorhynchus mykiss gairdneri is a species of high conservation concern in the Kootenai River basin, United States and Canada. However, identifying the specific mechanisms influencing Redband Trout is difficult as its life history structure is largely unknown. Using otolith microchemistry analysis, we found that 18.5% (n = 66) of...
Uppermost Oligocene and Miocene diatom biostratigraphy of Ocean Drilling Program Sites 682 and 688 from the Peru Margin
Jason Coenen, John A. Barron, Thomas J. DeVries
2025, Stratigraphy (22) 155-180
The diatom biochronology of ODP (Ocean Drilling Program) Holes 682A and 688E provides a detailed framework for refiningMiocene diatom zonation in the East Pisco Basin of southern Peru, establishing both a nearly complete offshore reference section and a correlation tool for the fragmentary onshore vertebrate-bearing deposits. This new biostratigraphic record...
Calcareous nannofossil biostratigraphy and floral response to environmental changes recorded in the Pliocene Yorktown Formation, southeastern Virginia, USA
Masayuki Utsunomiya, Harry J. Dowsett
2025, Stratigraphy (22) 181-193
The Pliocene Yorktown Formation, deposited on the U.S. Mid-Atlantic Coastal Plain, has played an important role in advancing our knowledge of Pliocene paleoclimate. To refine the age and paleoenvironment of the Yorktown Formation, we analyzed the calcareous nannofossil assemblage and compared it with variations in lithology and calculated sea surface...