Reports
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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.
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Low-head hydropower assessment of the Brazilian State of São Paulo Low-head hydropower assessment of the Brazilian State of São Paulo
This study produced a comprehensive estimate of the magnitude of hydropower potential available in the streams that drain watersheds entirely within the State of São Paulo, Brazil. Because a large part of the contributing area is outside of São Paulo, the main stem of the Paraná River was excluded from the assessment. Potential head drops were calculated from the Digital Terrain...
Authors
Guleid A. Artan, W. Matthew Cushing, Melissa L. Mathis, Larry L. Tieszen
Estimates of growth and mortality of under-yearling smallmouth bass in Spednic Lake, from 1970 through 2008 Estimates of growth and mortality of under-yearling smallmouth bass in Spednic Lake, from 1970 through 2008
This report is the product of a 2013 cooperative agreement between the U.S. Geological Survey, the International Joint Commission, and the Maine Bureau of Sea Run Fisheries and Habitat to quantify the effects of meteorological conditions (from 1970 through 2008) on the survival of smallmouth bass ( Micropterus dolomieu) in the first year of life in Spednic Lake. This report documents the...
Authors
Robert W. Dudley, Joan G. Trial
Long Valley Caldera 2003 through 2014: Overview of low level unrest in the past decade Long Valley Caldera 2003 through 2014: Overview of low level unrest in the past decade
Long Valley Caldera is located in California along the eastern escarpment of the Sierra Nevada Range. The caldera formed about 760,000 years ago as the eruption of 600 km3 of rhyolite magma (Bishop Tuff) resulted in collapse of the partially evacuated magma chamber. Resurgent doming in the central part of the caldera occurred shortly afterwards, and the most recent eruptions inside the...
Authors
Stuart K. Wilkinson, David P. Hill, John O. Langbein, Michael Lisowski, Margaret T. Mangan
Distribution and prevalence of knemidokoptic mange in Hawai`i `Amakihi on the island of Hawaii Distribution and prevalence of knemidokoptic mange in Hawai`i `Amakihi on the island of Hawaii
Knemidokoptic mange was first observed on two Hawai‘i ‘Amakihi (Hemignathus virens) mist netted in Manuka Natural Area Reserve (NAR) on the Island of Hawai‘i in June 2007. Microscopic examination of skin scrapings from lesions of the infested individuals revealed the scaley-leg mite, Knemidokoptes jamaicensis. Continued surveillance at Manuka NAR (2007-2009) documented a 24% (15/63)...
Authors
Jacqueline Gaudioso, Dennis LaPointe, Carter T. Atkinson, Chloe Apelgren
Productivity of forest birds at Hakalau Forest NWR Productivity of forest birds at Hakalau Forest NWR
Hawai‘i has some of the most endangered avian species in the world, which face numerous threats from habitat loss, disease, climate change, and introduced species. This report details the results of a two-year productivity study of all forest bird species at Hakalau National Wildlife Refuge, Hawai‘i Island. We found and monitored nests from seven native species and three common non...
Authors
Eben H. Paxton, George C Cummins, Steven J. Kendall
Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas
Sixteen aquifers in Arkansas that currently serve or have served as sources of water supply are described with respect to existing groundwater protection and management programs, geology, hydrologic characteristics, water use, water levels, deductive analysis, projections of hydrologic conditions, and water quality. State and Federal protection and management programs are described...
Authors
Timothy M. Kresse, Phillip D. Hays, Katherine R. Merriman, Jonathan A. Gillip, D. Todd Fugitt, Jane L. Spellman, Anna M. Nottmeier, Drew A. Westerman, Joshua M. Blackstock, James L. Battreal
Status of groundwater levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, 2012 to 2014 Status of groundwater levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, 2012 to 2014
Development of the Wichita well field in the Equus Beds aquifer in southwest Harvey County and northwest Sedgwick County began in the 1940s to supply water to the city of Wichita. The decline of water levels in the Equus Beds aquifer was noted soon after the development of the Wichita well field began. Development of irrigation wells began in the 1960s. City and agricultural withdrawals...
Authors
Cristi V. Hansen, Joshua A. Whisnant, Jennifer L. Lanning-Rush
Geologic framework for the national assessment of carbon dioxide storage resources: Williston Basin, Central Montana Basins, and Montana Thrust Belt study areas Geologic framework for the national assessment of carbon dioxide storage resources: Williston Basin, Central Montana Basins, and Montana Thrust Belt study areas
The 2007 Energy Independence and Security Act directs the U.S. Geological Survey (USGS) to conduct a national assessment of potential geologic storage resources for carbon dioxide (CO2). The methodology used by the USGS for the national CO2 assessment follows that of previous USGS work. This methodology is non-economic and is intended to be used at regional to sub-basinal scales. The...
Authors
Marc L. Buursink, Matthew D. Merrill, William H. Craddock, Tina L. Roberts-Ashby, Sean T. Brennan, Madalyn S. Blondes, P.A. Freeman, Steven M. Cahan, Christina A. DeVera, Celeste D. Lohr
A geologic and mineral exploration spatial database for the Stillwater Complex, Montana A geologic and mineral exploration spatial database for the Stillwater Complex, Montana
The Stillwater Complex is a Neoarchean, ultramafic to mafic layered intrusion exposed in the Beartooth Mountains in south-central Montana. This igneous intrusion contains magmatic mineralization that is variably enriched in strategic and critical commodities such as chromium, nickel, and the platinum-group elements. One deposit, the J-M Reef, is the sole source of primary production and...
Authors
Michael L. Zientek, Heather L. Parks
Groundwater-flow and land-subsidence model of Antelope Valley, California Groundwater-flow and land-subsidence model of Antelope Valley, California
Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley groundwater basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, groundwater provided more than 90 percent of the total water supply in the...
Authors
Adam J. Siade, Tracy Nishikawa, Diane L. Rewis, Peter Martin, Steven P. Phillips
Database for the geologic map of upper Eocene to Holocene volcanic and related rocks in the Cascade Range, Washington Database for the geologic map of upper Eocene to Holocene volcanic and related rocks in the Cascade Range, Washington
This geospatial database for a geologic map of the Cascades Range in Washington state is one of a series of maps that shows Cascade Range geology by fitting published and unpublished mapping into a province-wide scheme of lithostratigraphic units. Geologic maps of the Eocene to Holocene Cascade Range in California and Oregon complete the series, providing a comprehensive geologic map of...
Authors
Andrew D. Barron, David W. Ramsey, James G. Smith
Maps and geospatial data for the Shorty’s Island and Myrtle Bend substrate enhancement pilot projects, Kootenai River near Bonners Ferry, Idaho, 2014 Maps and geospatial data for the Shorty’s Island and Myrtle Bend substrate enhancement pilot projects, Kootenai River near Bonners Ferry, Idaho, 2014
The U.S. Geological Survey, in cooperation with the Idaho Department of Fish and Game, conducted a study to characterize the physical habitat occupied by Kootenai River white sturgeon during spawning and early-life phases. The objective was to gain a better understanding of spawning behavior, site selection, and type of habitat used during egg incubation in two sub-reaches of the...
Authors
Ryan L. Fosness