Groundwater-level elevations in the bedrock aquifers of the Denver Basin aquifer system, Elbert County, Colorado, 2015–23
Kelli M. Palko, Cory A. Russell, Nicholas J. Pieseski
2026, Scientific Investigations Report 2026-5115
Water users in Elbert County, Colorado, rely on groundwater from bedrock aquifers in the Denver Basin aquifer system (upper Dawson, lower Dawson, Denver, Arapahoe, and Laramie-Fox Hills aquifers) for approximately half of their water uses. Withdrawals from the bedrocks aquifers have increased to meet the water use needs of expanding...
Assessment of undiscovered conventional oil and gas resources in the Greater Carpathian area, 2024
Christopher J. Schenk, Tracey J. Mercier, Phuong A. Le, Andrea D. Cicero, Sarah E. Gelman, Jane S. Hearon, Benjamin G. Johnson, Jenny H. Lagesse, Heidi M. Leathers-Miller
2026, Fact Sheet 2026-3060
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 208 million barrels of oil and 4.1 trillion cubic feet of gas in the greater Carpathian area....
Millennial-scale climatic and cultural impacts on vegetation and fire at the southern edge of the Rocky Mountains, USA
Paul Henne, Susann Stolze, Natalie Kehrwald, Rebecca Lynn Brice, Craig Allen
2026, Quaternary Science Reviews (376)
Mountain forests and woodlands in semiarid regions of the world are threatened by climatic change and other human impacts. In the southwestern USA, climate and culturally driven changes to the structure and fire regimes of dry coniferous forests over recent centuries are well documented by tree-ring archives. However, the roles...
Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau
Marissa E. Mnich, Christopher D. Condit
2026, Professional Paper 1890-N
A detailed characterization of the >3,000 square kilometer (km2) Springerville volcanic field, located on the southern tip of the Colorado Plateau in Arizona, United States, with its more than 501 volcanic units and widely distributed >420 cinder cones and lava flows, provides constraints toward an integrated petrogenetic model for the...
Vegetation cover and composition in environments surrounding uranium mines in the Grand Canyon ecosystem, Northern Arizona
Rebecca K. Mann, Michael C. Duniway, Jo Ellen Hinck
2026, Open-File Report 2025-1024
Mining uranium from breccia-pipe deposits in the greater Grand Canyon region has occurred since the mid-1900s. However, possible ecosystem contamination with harmful levels of radionuclides may have occurred due to mining activities in the 21st century. In response, a 20-year Federal moratorium on new mining claims in the Grand Canyon...
ECCOE Landsat Quarterly Calibration and Validation Report—Quarter 2, 2025
Md Obaidul Haque, Nahid Hasan, Ashish Shrestha, Rajagopalan Rengarajan, Mark Lubke, Daniel Steinwand, Paul Bresnahan, Jerad L. Shaw, Kathryn Ruslander, Esad Micijevic, Michael J. Choate, Cody Anderson, Jeff Clauson, Kurt Thome, Amit Angal, Raviv Levy, Jeff Miller, Leibo Ding, Cibele Teixeira Pinto
2026, Open-File Report 2026-1059
Executive Summary The U.S. Geological Survey Earth Resources Observation and Science Calibration and Validation (Cal/Val) Center of Excellence (ECCOE) focuses on improving the accuracy, precision, calibration, and product quality of remote- sensing data, leveraging years of multiscale optical system geometric and radiometric calibration and characterization experience. The ECCOE Landsat Cal/Val Team...
Latest Pleistocene to 19th-century earthquakes on bending-moment reverse faults of the Seattle fault zone, Washington
Stephen J. Angster, Brian L. Sherrod, Jessie K. Pearl, Lydia M. Staisch, Wes Johns, Richard J. Blakely
2026, GSA Bulletin
Fault-related folds and their associated secondary faults play a critical yet often underrecognized role in accommodating strain and generating earthquakes in active fold-and-thrust belts. In the Seattle fault zone (SFZ), Washington, USA, we present new paleoseismic, geomorphic, and geophysical evidence for late Pleistocene and Holocene earthquakes on...
Sea-level rise in a coastal marsh: Linking increasing tidal inundation, decreasing soil strength and increasing pond expansion
Mona Huyzentruyt, Lennert Schepers, Matthew Kirwan, Glenn Guntenspergen, Stijn Temmerman
2026, Biogeosciences (23) 751-766
Coastal marsh conversion into ponds, which may be triggered by sea-level rise, is considered an important driver of marsh loss and their valuable ecosystem services. Previous studies have focused on the role of wind waves in driving the expansion of interior marsh ponds, through lateral erosion of marsh edges surrounding...
Recent scientific contributions by the U.S. Geological Survey in the San Francisco Bay and Sacramento–San Joaquin Delta Estuary
Judith Z. Drexler, Jake F. Weltzin
2026, Fact Sheet 2025-3058
Introduction The San Francisco Bay and Sacramento–San Joaquin Delta Estuary (hereafter, Bay-Delta) is the largest estuary on the West Coast of the United States. The Bay- Delta covers more than 1,600 square miles and drains a watershed of more than 75,000 square miles, which is greater than 40 percent of California....
Multi-year cut-to-drown management limits Phragmites australis growth, belowground resources, and rhizome viability in Great Lakes wetlands
Wesley A. Bickford, Kaira A. Schaefer, Spenser L. Widin, Kurt P. Kowalski
2026, Journal of Great Lakes Research
The distribution and abundance of Phragmites in the Great Lakes coastal zone has expanded in part due to its unique ventilation physiology and its ability to take advantage of changes in lake levels over the past several decades. During an extended period of low lake levels in the early...
Prioritizing resource protection and understanding potential susceptibility of springs to surficial changes in a low-temperature geothermal system
Connor P. Newman, Jeff D. Pepin
2026, Geothermics (136)
Geothermal systems are vulnerable to changes in water budget and composition, requiring science-based management. This study uses a dataset of spring water temperatures, time series of groundwater residence time tracers (tritium and carbon-14), and stable isotopes of water to understand geothermal flow in a low-temperature geothermal system in north west...
Per- and polyfluoroalkyl substances (PFAS) and other contaminants of concern in tribal waters of Montana
Kelly L. Smalling, Paul M. Bradley, Kristin M. Romanok, John T. Doyle, Margaret J. Eggers, Christine Martin, Elliott P. Barnhart, Picabo Binette, Eric M. Castro, Madisan Chavez, Stephanie A. Ewing, Stephanie E. Gordon, Mathew W. Fields, James L. Gray, Ashley M. Groshong, Chiachi Hwang, Leslie K. Kanagy, JoRee WClay LaFrance, Keith A. Loftin, Carrie Mae Long, R. Blaine McCleskey, Shannon M. Meppelink, Crystal L. Richards, Molly L. Schreiner, Jonathan I. Shikany, Mahelat Tesfamariam
2026, Environmental Science: Processes & Impacts
We assessed potential exposures to a broad suite of contaminants (inorganic, organic and microbial) in culturally important surface waters from three watersheds in a northern plains Native American community (Apsáalooke [Crow Tribe of Montana]) in south-central Montana, United States, with water insecurity concerns. Inorganic (37), organic (435)...
Surface variable‐based machine learning for scalable arsenic prediction in undersampled areas
Shams Azad, Mason O. Stahl, Melinda Erickson, Beck A. DeYoung, Craig T. Connolly, Lawrence Chillrud, Kathrin Schilling, Ana Navas-Acien, Anirban Basu, Brian Mailloux, Benjamin C. Bostick, Steven N. Chillrud
2026, GeoHealth (10)
In the United States, private wells are not federally regulated, and many households do not test for Arsenic (As). Chronic exposure is linked with multiple health outcomes, and risk can change sharply over short distances and with well depth. Coarse maps or sparse sampling often miss exceedances....
Assessing the influence of conservation implementation on water quality during surface runoff events at edge-of-field monitoring sites located in the Laurentian Great Lakes basin
Brittany Rose Hanrahan, Matthew W. Diebel, Rebecca B. Carvin, Edward G. Dobrowolski, Matthew John Hardebeck, Andrew Jason Kowalczk, Chad A. Toussant, Matthew J. Komiskey
2026, Journal of Soil and Water Conservation
The Laurentian Great Lakes are a vital freshwater resource in the United States, and nonpoint source (NPS) nutrient pollution, specifically phosphorus (P) and nitrogen (N), from agricultural land use continues to negatively impact water quality throughout the Great Lakes basin. One focus of the Great Lakes Restoration...
Strength of depensation not influenced by fish population productivity
Greg S. Sass, Joesph T. Mrnak, Stephanie L Shaw, Zachary S. Feiner, Colin J. Dassow, Andrew L. Rypel, Holly Susan Embke
2026, Fisheries Research (294)
A long-held assumption in the management of exploited fisheries is that fish populations will compensate with increased recruit survival to replenish the population when adult stock size is reduced through harvest. Observations of depensatory recruitment (reduced recruit survival at low adult stock size) and critical depensatory thresholds have challenged the...
Mountain goat declines in a protected, interior, native population
Tabitha A. Graves, William Michael Janousek, Michael Yarnall, Jami Belt
2026, Ecosphere (17)
A shifting climate poses threats to alpine-adapted species including mountain goats. We used long-term (12 years) citizen science monitoring data and Bayesian N-mixture modeling to estimate population trends and drivers of population metrics among mountain goats in Glacier National Park (GNP). Median goats per site (n = 37 sites) declined by 45% (95%...
Miocene evolution of the Humboldt Current
John A. Barron, Thomas J. DeVries, Jason J. Coenen
2026, Palaeogeography, Palaeoclimatology, Palaeoecology (686)
Diatom records from the East Pisco Basin (EPB) of southern Peru and offshore Ocean Drilling Program (ODP) Hole 682 A reveal stepwise increases in the primary productivity of the Humboldt Current during the middle and late Miocene. Although diatoms are present back through the late middle Eocene, successively enhanced diatom production...
Compilation of a nationwide river image dataset for identifying river channels and river rapids via deep learning
Nicholas Brimhall, Kelvyn K. Bladen, Tom Kerby, Carl J. Legleiter, Cameron Swapp, Hannah Fluckiger, Julie E Bahr, Makenna Roberts, Kaden Hart, Christina L. Stegman, Brennan Bean, Kevin Moon
2026, Remote Sensing (18)
Remote sensing enables large-scale, image-based assessments of river dynamics, offering new opportunities for hydrological monitoring. We present a publicly available dataset consisting of 281,024 satellite and aerial images of U.S. rivers, constructed using an Application Programming Interface (API) and the U.S. Geological Survey’s National Hydrography Dataset. The dataset includes images,...
The biosphere in the Anthropocene
Mark Williams, Mary L. McGann, Moriaki Yasuhara, Chhaya Chaudhary, Lisa Barber, Kerry Allen
2026, Transactions of the Royal Society of London (381)
Earth’s biosphere is in a period of rapid change, resulting from anthropogenic pressures such as climate change, habitat loss and species translocation and extinction. The extraordinary pace of change has led to the suggestion that we live in a new geological epoch of time called the Anthropocene....
Bedrock geologic map of the Eagle Lake quadrangle, Essex County, New York
Gregory J. Walsh, Sean P. Regan, Phillip S. Geer, Arthur J. Merschat, Kaitlyn A. Suarez, Ryan J. McAleer, Matt S. Walton, Jr., E. Allen Crider, Jr.
2026, Scientific Investigations Map 3542
The bedrock geology of the 7.5-minute Eagle Lake quadrangle, Essex County, New York, consists of deformed and metamorphosed Mesoproterozoic gneisses of the Adirondack Highlands unconformably overlain by weakly deformed lower Paleozoic sedimentary rocks of the Champlain Valley. The Mesoproterozoic rocks occur on the eastern edge of the Adirondack Highlands and...
An energetic tradeoff best explains parturition timing in grizzly bears
C. M. Costello, L. L. Roberts, D. D. Bjornlie, M. D. Cameron, J. G. Clapp, Mark Haroldson, G. V. Hilderbrand, K. Joly, W. Kasworm, J. M. Nicholson, T. Radandt, M. S. Sorum, J. E. Teisberg, Frank T. van Manen, M. A. Vinks
2026, Ecology and Evolution (16)
Timing of grizzly bear (Ursus arctos) parturition during hibernation has been explained by ancestral traits (delayed implantation, altricial young, obligate maternal denning), but the ultimate driver underlying precise timing has not been fully explored. Capitalizing on an observed latitudinal increase in denning duration among four populations in interior North America,...
Distribution, abundance, breeding activities, and habitat use of the Least Bell's Vireo at Marine Corps Base Camp Pendleton, California—2020–24 summary report
Suellen Lynn, Alexandra Houston, Barbara E. Kus, Shannon M. Mendia
2026, Open-File Report 2025-1057
Executive Summary The purpose of this report is to provide the Marine Corps with a summary of abundance, breeding activity, demography, and habitat use of endangered Least Bell’s Vireos (Vireo bellii pusillus) at Marine Corps Base Camp Pendleton, California (MCBCP or Base). The report presents results of vireo surveys and monitoring...
Comparison of two precipitation gage networks in Cook County, Illinois
Kevin K. Johnson
2026, Scientific Investigations Report 2025-5102
The Cook County Precipitation Network is a set of 25 precipitation gages established within Cook County, Illinois, on approximately a 5- to 7-mile square grid and used by the U.S. Army Corps of Engineers to help account for diversions of water from Lake Michigan to the State of Illinois. The...
Widespread terrestrial ecosystem disruption at the onset of the Paleocene–Eocene Thermal Maximum
Mei Nelissen, Debra A. Willard, Han Konijnenburg-van Cittert, Gabriel J. Bowen, Teuntje Hollaar, Appy Sluijs, Joost Frieling, Henk Brinkhuis
2026, Proceedings of the National Academy of Sciences (123)
The Paleocene–Eocene Thermal Maximum (PETM, ~56 Mya) interval was marked by massive 13C-depleted carbon emissions into the ocean/atmosphere system, manifested as a negative carbon isotope excursion (CIE) in sedimentary components, and ~5 °C global average warming. Episodes of hydrological perturbations and soil-erosion have been widely documented for the PETM but their...
Toxicity of anticoagulant rodenticides on Pacific salmon: Assessing lethal and sublethal effects
Lillian M. Pavord, Melissa K. Driessnack, Aaron B. Shiels, Steven Volker, Barnett A. Rattner, Jenifer McIntyre
2026, Ecotoxciology and Environmental Safety (310)
To restore native biodiversity on island ecosystems containing invasive rodents, partial- and whole-island eradications generally rely on broadcast baiting with anticoagulant rodenticides (ARs). This approach can result in bait pellets entering aquatic environments, raising concerns about effects to non-target fish. Salmonids are a dominant group of fishes on many temperate...
