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: 84615
Groundwater-level elevations in the bedrock aquifers of the Denver Basin aquifer system, Elbert County, Colorado, 2015–23 Groundwater-level elevations in the bedrock aquifers of the Denver Basin aquifer system, Elbert County, Colorado, 2015–23
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 regional population growth and development. The U.S...
Authors
Kelli M. Palko, Cory A. Russell, Nicholas J. Pieseski
Assessment of undiscovered conventional oil and gas resources in the Greater Carpathian area, 2024 Assessment of undiscovered conventional oil and gas resources in the Greater Carpathian area, 2024
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.
Authors
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
Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau
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 field. Large-volume effusive tholeiitic eruptions at...
Authors
Marissa E. Mnich, Christopher D. Condit
Vegetation cover and composition in environments surrounding uranium mines in the Grand Canyon ecosystem, Northern Arizona Vegetation cover and composition in environments surrounding uranium mines in the Grand Canyon ecosystem, Northern Arizona
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 watershed was initiated in 2012, to allow time to...
Authors
Rebecca K. Mann, Michael C. Duniway, Jo Ellen Hinck
ECCOE Landsat Quarterly Calibration and Validation Report—Quarter 2, 2025 ECCOE Landsat Quarterly Calibration and Validation Report—Quarter 2, 2025
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...
Authors
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
Recent scientific contributions by the U.S. Geological Survey in the San Francisco Bay and Sacramento–San Joaquin Delta Estuary Recent scientific contributions by the U.S. Geological Survey in the San Francisco Bay and Sacramento–San Joaquin Delta Estuary
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. The region surrounding the Bay- Delta is home to about 10 million people...
Authors
Judith Z. Drexler, Jake F. Weltzin