Reports
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 82,000 reports authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
Filter Total Items: 85162
Guide and data requirements for submission of mineral deposit mineral chemistry data in the Critical Minerals in Ores - Mineral Chemistry (CMiO-MIN) database Guide and data requirements for submission of mineral deposit mineral chemistry data in the Critical Minerals in Ores - Mineral Chemistry (CMiO-MIN) database
The Critical Minerals in Ores - Mineral Chemistry (CMiO-MIN) database (Hawkins et al., 2026) is designed to capture ore and ore-related mineral compositional data from critical mineral-bearing deposits across the globe. Samples included within this database must be well-characterised and come from localities that have been sufficiently studied to have a reasonable constraint on their...
Authors
Steph G. Hawkins, Garth E. Graham, Duane C. Petts, M.G. Gadd, Cait A. Stuart, Erik Roger Tharalson
Paleogene landscape and basin evolution in the Missouri River Headwater region of the Basin and Range Province in southwestern Montana: Implications for Paleogene extensional tectonic models and magmatism Paleogene landscape and basin evolution in the Missouri River Headwater region of the Basin and Range Province in southwestern Montana: Implications for Paleogene extensional tectonic models and magmatism
No abstract available.
Authors
Robert K. Schwartz, Theresa Maude Schwartz, Colleen G. Elliott
Appendix 6: Overview of iPOM 2.0: Updates to wolf abundance estimation in Montana Appendix 6: Overview of iPOM 2.0: Updates to wolf abundance estimation in Montana
Montana Fish, Wildlife and Parks (MFWP) uses the integrated Patch Occupancy Model (iPOM) to estimate statewide and regional wolf abundance. During the early years of recovery, wolf abundance was tracked using minimum counts. As the population increased, limitations of this method became apparent, motivating development of a model-based approach for estimating abundance. iPOM development...
Authors
Sarah Nelson Sells, Hannah A. Sipe, Thomas Riecke, Justin Gude, Molly Parks, Kevin M. Podruzny, Wendy Cole, Nathan J. Lance, Tyler W. Parks, Matt Thorpe, Sarah Zielke
Volcanic activity in Alaska and the Northern Mariana Islands in 2024—Summary of events and response of the Alaska Volcano Observatory Volcanic activity in Alaska and the Northern Mariana Islands in 2024—Summary of events and response of the Alaska Volcano Observatory
In 2024, the Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 10 volcanic centers in Alaska and the Northern Mariana Islands. Eruptive activity in Alaska consisted of the eruption of a thick lava flow within the summit crater at Great Sitkin Volcano throughout the entire year and a small...
Authors
Tim R. Orr, Ronni Grapenthin, David Fee, Hannah R. Dietterich, Aaron Wech, Peter J. Kelly, Taryn M. Lopez
Improving offshore 3D splay fault geometries and slip histories using seismic data reprocessing and structural modeling Improving offshore 3D splay fault geometries and slip histories using seismic data reprocessing and structural modeling
The goal of this project as written in the CRESCENT seed grant proposal was as follows: 1) reprocess selected profiles along strike from 45° to 48°N from the CASIE21 crustal-scale seismic data to obtain higher-resolution and higher-quality imaging of the uppermost 1-2 km of the accretionary wedge; 2) convert high-resolution USGS sparker seismic data from the time to depth domain to...
Authors
Anna M. Ledeczi, Nathaniel C. Miller, Harold J. Tobin, Cailey B. Condit
Range-wide relative abundance of the Appalachian grizzled skipper (Pyrgus centaureae wyandot) in the Eastern United States Range-wide relative abundance of the Appalachian grizzled skipper (Pyrgus centaureae wyandot) in the Eastern United States
The U.S. Fish and Wildlife Service has designated the Pyrgus centaureae wyandot (Appalachian Grizzled Skipper [AGS]) to be at-risk, based on its declining populations and the lack of information on its status. The objective of this study was to complete range-wide surveys to locate extant AGS colonies and to quantify the number of AGS observed at each location. From 2021–24, 284 surveys...
Authors
Nimish B. Vyas, Jennifer Selfridge, David Cuthrell, Robert Somes, Erin White, Judith Ratcliffe, J. Merrill Lynch, Laurie Hamon, Eileen Wyza, Betsy Leppo, Pete Woods, Anthony Tur, Donovan Drummey, Kathryn Nolan, Ellison Orcutt, Andrew Rapp, Leah Card, Jakob Goldner, Susan Olcott
Status and trends of pelagic and benthic prey fish populations in Lake Michigan, 2025 Status and trends of pelagic and benthic prey fish populations in Lake Michigan, 2025
Fall bottom trawl (fall BT) and lakewide acoustic (AC) surveys are conducted annually to generate indices of pelagic and benthic prey fish densities in Lake Michigan. The fall BT survey has been conducted each fall since 1973 using 12-m trawls at depths ranging from 9 to 110 m at fixed locations distributed across seven transects; this survey estimates densities of seven prey fish...
Authors
Ralph W. Tingley, Timothy P. O’Brien, Charles P. Madenjian, Peter C. Esselman, Patricia Dieter, Kristy Phillips, Ben Turschak, Dale Hanson, Steven A. Farha
Continuous and high-resolution longitudinal profiles of the water surface and riverbed elevation for 282 miles of the Colorado River from Lees Ferry to Pearce Ferry, Arizona, 2021 Continuous and high-resolution longitudinal profiles of the water surface and riverbed elevation for 282 miles of the Colorado River from Lees Ferry to Pearce Ferry, Arizona, 2021
Longitudinal profiles of water surface and riverbed elevations capture key geomorphic characteristics that can be affected by water infrastructure and natural processes. Continuous water surface profiles of the Colorado River in Grand Canyon, a river influenced by two of the largest dams in the United States, have been measured infrequently. The water surface profile was first measured...
Authors
Shannon L. Sartain, Matthew A. Kaplinski, Keith Kohl, Katherine A. Chapman, Nathaniel D. Bransky, Joel B. Sankey, Paul E. Grams
High-resolution transboundary vegetation community maps of the Sonoran and Mojave Desert ecoregion to support critical landscape conservation planning and habitat management needs High-resolution transboundary vegetation community maps of the Sonoran and Mojave Desert ecoregion to support critical landscape conservation planning and habitat management needs
We produced a 30-m resolution binational land cover map of Bird Conservation Region 33 (BCR 33) for the U.S. North American Bird Conservation Initiative. The region covers large portions of the Sonoran and Mojave Deserts. The map can support the U.S. Fish and Wildlife Service (FWS) Migratory Bird Program’s recovery planning efforts and constitutes the first known binational land cover...
Authors
Pamela L Nagler, Jennie N. Duberstein, James Broska, Kamel Didan, Myles B. Traphagen
Critical minerals memory match game Critical minerals memory match game
An educational information packet about the 2025 List of Critical Minerals, which includes a memory match game about select critical minerals and how they are used.
Authors
Danielle A. Olinger
The Great Lakes Geologic Mapping Coalition—Working collaboratively to understand the geology of the Great Lakes Region The Great Lakes Geologic Mapping Coalition—Working collaboratively to understand the geology of the Great Lakes Region
Authors
Brianna Lopez, Jenna L. Shelton, Michael Marketti, Kate Ritzel, Brandon L. Graham
Assessment of undiscovered conventional oil and gas resources in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa, 2026 Assessment of undiscovered conventional oil and gas resources in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa, 2026
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 419 million barrels of oil and 5.5 trillion cubic feet of gas in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa.
Authors
Christopher J. Schenk, Tracey J. Mercier, Cheryl A. Woodall, Thomas M. Finn, Heidi M. Leathers-Miller, Michael E. Brownfield, Phuong A. Le, Stephanie B. Gaswirth, Marilyn E. Tennyson