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: 84795
Estimation of a Trophic State Index for selected inland lakes in Michigan, 1999–2013 Estimation of a Trophic State Index for selected inland lakes in Michigan, 1999–2013
A 15-year estimated Trophic State Index (eTSI) for Michigan inland lakes is available, and it spans seven datasets, each representing 1 to 3 years of data from 1999 to 2013. On average, 3,000 inland lake eTSI values are represented in each of the datasets by a process that relates field-measured Secchi-disk transparency (SDT) to Landsat satellite imagery to provide eTSI values for...
Authors
Lori M. Fuller, Richard S. Jodoin
GIS representation of coal-bearing areas in Antarctica GIS representation of coal-bearing areas in Antarctica
Understanding the distribution of coal-bearing geologic units in Antarctica provides information that can be used in sedimentary, geomorphological, paleontological, and climatological studies. This report is a digital compilation of information on Antarctica’s coal-bearing geologic units found in the literature. It is intended to be used in small-scale spatial geographic information...
Authors
Matthew D. Merrill
Assessing the socioeconomic impact and value of open geospatial information Assessing the socioeconomic impact and value of open geospatial information
The production and accessibility of geospatial information including Earth observation is changing greatly both technically and in terms of human participation. Advances in technology have changed the way that geospatial data are produced and accessed, resulting in more efficient processes and greater accessibility than ever before. Improved technology has also created opportunities for...
Authors
Francoise Pearlman, Jay Pearlman, Richard Bernknopf, Andrew Coote, Massimo Craglia, Lawrence Friedl, Jason Gallo, Henry Hertzfeld, Claire Jolly, Molly K. Macauley, Carl Shapiro, Alan Smart
Assessment of undiscovered hydrocarbon resources of sub-Saharan Africa Assessment of undiscovered hydrocarbon resources of sub-Saharan Africa
Introduction The main objective of the U.S. Geological Survey’s (USGS) National and Global Petroleum Assessment Project is to assess the potential for undiscovered, technically recoverable oil and natural gas resources of the United States and the world (U.S. Geological Survey World Conventional Resources Assessment Team, 2012). The USGS updated assessments that were completed during the...
Authors
Michael E. Brownfield
Effects of streamflows on stream-channel morphology in the eastern Niobrara National Scenic River, Nebraska, 1988–2010 Effects of streamflows on stream-channel morphology in the eastern Niobrara National Scenic River, Nebraska, 1988–2010
The Niobrara River is an important and valuable economic and ecological resource in northern Nebraska that supports ecotourism, recreational boating, wildlife, fisheries, agriculture, and hydroelectric power. Because of its uniquely rich resources, a 122-kilometer reach of the Niobrara River was designated as a National Scenic River in 1991, which has been jointly managed by the U.S...
Authors
Nathaniel J. Schaepe, Jason S. Alexander, Kiernan Folz-Donahue
The effect of suspended sediment and color on ultraviolet spectrophotometric nitrate sensors The effect of suspended sediment and color on ultraviolet spectrophotometric nitrate sensors
Four commercially available ultraviolet nitrate spectrophotometric sensors were evaluated by the U.S. Geological Survey Hydrologic Instrumentation Facility (HIF) to determine the effects of suspended sediment concentration (SSC) and colored dissolved organic matter (CDOM) on sensor accuracy. The evaluated sensors were: the Hach NITRATAX plus sc (5-millimeters (mm) path length), Hach...
Authors
Teri T. Snazelle
Hydrologic conditions, recharge, and baseline water quality of the surficial aquifer system at Jekyll Island, Georgia, 2012-13 Hydrologic conditions, recharge, and baseline water quality of the surficial aquifer system at Jekyll Island, Georgia, 2012-13
An increase of groundwater withdrawals from the surficial aquifer system on Jekyll Island, Georgia, prompted an investigation of hydrologic conditions and water quality by the U.S. Geological Survey during October 2012 through December 2013. The study demonstrated the importance of rainfall as the island’s main source of recharge to maintain freshwater resources by replenishing the water...
Authors
Debbie W. Gordon, Lynn J. Torak
Network global navigation satellite system surveys to harmonize American and Canadian datum for the Lake Champlain Basin Network global navigation satellite system surveys to harmonize American and Canadian datum for the Lake Champlain Basin
Historically high flood levels were observed during flooding in Lake Champlain and the Richelieu River from late April through May 2011. Flooding was caused by record spring precipitation and snowmelt from the third highest cumulative snowfall year on record, which included a warm, saturated late spring snowpack. Flood stage was exceeded for a total of 67 days from April 13 to June 19...
Authors
Robert H. Flynn, Paul H. Rydlund, Daniel J. Martin
Identifying and preserving high-water mark data Identifying and preserving high-water mark data
High-water marks provide valuable data for understanding recent and historical flood events. The proper collection and recording of high-water mark data from perishable and preserved evidence informs flood assessments, research, and water resource management. Given the high cost of flooding in developed areas, experienced hydrographers, using the best available techniques, can contribute...
Authors
Todd A. Koenig, Jennifer L. Bruce, Jim O’Connor, Benton D. McGee, Robert R. Holmes, Ryan Hollins, Brandon T. Forbes, Michael S. Kohn, Mathew Schellekens, Zachary W. Martin, Marie C. Peppler
DOI/GTN-P Climate and active-layer data acquired in the National Petroleum Reserve–Alaska and the Arctic National Wildlife Refuge, 1998–2014 DOI/GTN-P Climate and active-layer data acquired in the National Petroleum Reserve–Alaska and the Arctic National Wildlife Refuge, 1998–2014
This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2014; this array is part of the Global Terrestrial Network for Permafrost (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methods. The array...
Authors
Frank E. Urban, Gary D. Clow
Groundwater quality, age, and susceptibility and vulnerability to nitrate contamination with linkages to land use and groundwater flow, Upper Black Squirrel Creek Basin, Colorado, 2013 Groundwater quality, age, and susceptibility and vulnerability to nitrate contamination with linkages to land use and groundwater flow, Upper Black Squirrel Creek Basin, Colorado, 2013
The Upper Black Squirrel Creek Basin is located about 25 kilometers east of Colorado Springs, Colorado. The primary aquifer is a productive section of unconsolidated deposits that overlies bedrock units of the Denver Basin and is a critical resource for local water needs, including irrigation, domestic, and commercial use. The primary aquifer also serves an important regional role by the...
Authors
Tristan P. Wellman, Michael G. Rupert
Get your science used—Six guidelines to improve your products Get your science used—Six guidelines to improve your products
Introduction Natural scientists, like many other experts, face challenges when communicating to people outside their fields of expertise. This is especially true when they try to communicate to those whose background, knowledge, and experience are far distant from that field of expertise. At a recent workshop, experts in risk communication offered insights into the communication...
Authors
Suzanne C. Perry, Michael L. Blanpied, Erin R. Burkett, Nnenia M. Campbell, Anders Carlson, Dale A. Cox, Carolyn L. Driedger, David P. Eisenman, Katherine T. Fox-Glassman, Sherry Hoffman, Susanna M. Hoffman, Kishor S. Jaiswal, Lucile M. Jones, Nico Luco, Sabine M. Marx, Sean M. McGowan, Dennis S. Mileti, Morgan P. Moschetti, David Ozman, Elizabeth Pastor, Mark D. Petersen, Keith A. Porter, David W. Ramsey, Liesel A. Ritchie, Jessica K. Fitzpatrick, Kenneth S. Rukstales, Timothy L. Sellnow, Wendy L. Vaughon, David J. Wald, Lisa A. Wald, Anne Wein, Christina Zarcadoolas