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Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

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At least 253 records · Page 14Linked to original sources
USGS1983

The role of the USFWS geographic information system in coastal decisionmaking

Unprecedented demand on coastal resources in the 1980's has generated a need for valid information and analyses to support wise management of the coastal zone. The National Coastal Ecosystems Team of the U.S. Fish and Wildlife Service recently implemented a geographic information system to enhance its ability to analyze and display environmental information about the coastal zone. Outputs from this system have been presented to the State of Louisiana Senate and House Committees on Natural Resources and to the Congressional House of Representatives Committee on Merchant Marine and Fisheries. The purpose of this paper is to describe the use of the Map Overlay Statistical System for addressing selected coastal issues and to discuss its utility for coastal decisionmaking.

Alabama, Florida, Louisiana, Mississippi, Texas↗
USGS2008

Digital surfaces and thicknesses of selected hydrogeologic units within the Mississippi Embayment Regional Aquifer Study (MERAS)

Digital surfaces of selected Tertiary and younger age hydrogeologic units within the Mississippi embayment aquifer system were created using more than 2,600 geophysical logs for an area that covers approximately 70,000 square miles and encompasses parts of eight states. The digital surfaces were developed to define and display the hydrogeologic framework for the Mississippi Embayment Regional Aquifer Study (MERAS). The digital surfaces also provide a foundation of the selected hydrogeologic units for development of a steady-state and transient regional ground-water flow model of the Mississippi embayment aquifer system from the top of the Midway confining unit upwards to land surface. The ground-water flow model is under development as part of the U.S. Geological Survey Ground-Water Resources Program. Using a Geographic Information System, nine digital surfaces of the tops of selected hydrogeologic units were created using the Australian National University Digital Elevation Model method as an interpolation scheme. Thickness maps also were constructed using the Geographic Information System by calculating the difference between the altitude of the interpreted base of an overlying unit and the altitude of the interpreted top of an underlying unit. In general, the highest hydrogeologic unit altitudes are located along the eastern edge of the study area in the outcrop, and the lowest altitudes, in general, are located along the southern edge of the study area along the axis of the embayment. The Mississippi River Valley alluvial aquifer and the lower Claiborne aquifer are the thinnest aquifers of importance in the study area; the thickest aquifer of importance is the middle Claiborne aquifer.

Mississippi Embayment Regional Aquifer↗
USGS2006

History of the Fort Collins Science Center, U.S. Geological Survey

The U.S. Geological Survey’s Fort Collins Science Center ("the Center") has been a nucleus of research, technology development, and associated scientific activities within the Department of the Interior for more than 30 years. The Center’s historical activities are deeply rooted in federal biological resources research and its supporting disciplines, particularly as they relate to the needs of the U.S. Department of the Interior and its resource management agencies. The organizational framework and activities of the Center have changed and adapted over the years in response to shifts in the scientific issues and challenges facing the U.S. Department of the Interior and with the development of new strategies to meet these challenges. Thus, the history of the Center has been dynamic. The Center has been nested within the U.S. Geological Survey since 1996. From 1993 to 1996 the Center was a major unit of the National Biological Service (named the National Biological Survey at its inception). This was a period of great organizational flux. During that time the Center comprised multiple field stations and science functions that prior to 1993 had been scattered among the U.S. Bureau of Land Management, the U.S. Bureau of Reclamation, the National Park Service, and the U.S. Fish and Wildlife Service. In 1993, certain biological research components of these agencies were assigned to join with the National Ecology Research Center, formerly one of the major research and development hubs of the U.S. Fish and Wildlife Service. This was the year when biological resources research in the U.S. Department of the Interior was consolidated by the Secretary of the Interior, who in an April 1993 memo explaining his intentions wrote, "Our Department has, without doubt, the best biologists in the world." Soon after formation of the new agency, the Center was re-named the Midcontinent Ecological Science Center, reflecting its geographic location within the new Midcontinent administrative region of the National Biological Service (the other three original administrative regions were the eastern, western, and southern). The change in name to the Fort Collins Science Center took place in 2002, soon after the center moved to new facilities on the Colorado State University Natural Resources Research Campus. At various times during the period when it was part of the National Biological Service (1993–96), the Center served as the administrative and programmatic home base for a wide number of science activities in numerous Western states (table 1). This reflected the previous fragmentation of biological and related science efforts across resource management agencies in the U.S. Department of the Interior. The organization of the 2 Center within the National Biological Service was a manifestation of the desire of the Secretary of the Interior to consolidate its biological science activities in administratively independent entities that would ensure that the science retained its objectivity. Congress later recognized the need to maintain a hierarchical independence between biological science and resource management in the Department. However, Congress also saw that the U.S. Geological Survey, with its long history of objective science support to the nation in geology, water resources, geography, and remote sensing, was a suitable alternative home for these biological science functions. Thus, in 1996 Congress transferred the biological resources functions of the National Biological Service to the U.S. Geological Survey. Detailed overviews and opinions about the history and policy issues surrounding the formation and subsequent fate of the National Biological Service can be found elsewhere (for example Cohn, 1993, 2005; Kaufman, 1993; Kreeger, 1994; Pulliam, 1995, 1998a,b; Reichhardt, 1994; Wagner, 1999)

Open-File Report↗
USGS1999

The National Hydrography Dataset

The National Hydrography Dataset (NHD) is a newly combined dataset that provides hydrographic data for the United States. The NHD is the culmination of recent cooperative efforts of the U.S. Environmental Protection Agency (USEPA) and the U.S. Geological Survey (USGS). It combines elements of USGS digital line graph (DLG) hydrography files and the USEPA Reach File (RF3). The NHD supersedes RF3 and DLG files by incorporating them, not by replacing them. Users of RF3 or DLG files will find the same data in a new, more flexible format. They will find that the NHD is familiar but greatly expanded and refined. The DLG files contribute a national coverage of millions of features, including water bodies such as lakes and ponds, linear water features such as streams and rivers, and also point features such as springs and wells. These files provide standardized feature types, delineation, and spatial accuracy. From RF3, the NHD acquires hydrographic sequencing, upstream and downstream navigation for modeling applications, and reach codes. The reach codes provide a way to integrate data from organizations at all levels by linking the data to this nationally consistent hydrographic network. The feature names are from the Geographic Names Information System (GNIS). The NHD provides comprehensive coverage of hydrographic data for the United States. Some of the anticipated end-user applications of the NHD are multiuse hydrographic modeling and water-quality studies of fish habitats. Although based on 1:100,000-scale data, the NHD is planned so that it can incorporate and encourage the development of the higher resolution data that many users require. The NHD can be used to promote the exchange of data between users at the national, State, and local levels. Many users will benefit from the NHD and will want to contribute to the dataset as well.

Fact Sheet↗
USGS2022

Preliminary national-scale seismic risk assessment of natural gas pipelines in the United States

Although the gas pipeline infrastructure in the United States is vulnerable to the seismic hazards of (i) strong ground shaking, and (ii) ground failures induced by surface faulting, liquefaction, or landslides, limited national guidance exists for operators to consistently evaluate the earthquake response of their pipelines. To provide additional information for stakeholders and establish more consistency at a national scale, we attempt to quantify seismic risk for gas transmission pipelines in the conterminous United States using a metric such as average annual loss, which helps readily distinguish geographic areas of high and low relative risk. Specifically, we integrate the 2018 National Pipeline Mapping System, the 2018 National Seismic Hazard Model, and several candidate models from the literature for estimating pipeline damage. Through this effort, we highlight major research needs for ultimately reducing the many uncertainties associated with a comprehensive seismic risk assessment of gas pipelines.

conterminous United States↗
USGS1990

U.S. Geological Survey National Computer Technology Meeting; Program and abstracts, May 7-11, 1990

he Water Resources Division of the U.S. Geological Survey has made major advancements in the use of computer technology to meet the Survey‘s mission of providing the hydrologic information and understanding needed for the optimum use and management of the Nation’s water resources. The Division requires substantial computer technology to process, store, and analyze data from about 60,000 sites. To meet this workload, the Division organized its computer resources in 1982 through the Distributed Information System (DIS) Program Office, which manages the Division's national network of computers. The DIS is designed to provide computer resources in support of the Division’s current and future activities -acquisition and storage of hydrologic information, hydrologic data analysis, geographic information systems, reports and electronic report processing, and administration. The Water Resources Division sponsored the first DIS Site Administrators Meeting in March 1984 in Denver, Colorado, and a second meeting in October 198.5 in Hyannis, Massachusetts. The thrust of the first two national meetings was the training of Water Resources Division personnel in the use and administration of the Division’s computer hardware and software. Starting with the third meeting, which was held in Atlanta, Georgia, in May 1987, the name was changed to the National Computer Technology Meeting because the format evolved to include presentation of papers prepared by computer and scientific personnel in the Division. These papers document work done in the field of computer science as applied to hydrology, including the design and use of geographic information systems, use of nationally distributed software, the development of procedures for data-base management, and research papers on the expanding field of computer technology. Training continues to be a major part of the National Computer Technology Meeting. This year’s meeting includes training on the use of UNIX operating system, UNIX system administration and security, the C programming language, local area networking, as well as a publication seminar. This report includes abstracts for papers and posters that have been accepted for presentation at the Fifth National Computer Technology Meeting.

Open-File Report↗
USGS2015

Back-Island and Open-Ocean Shorelines, and Sand Areas of the Undeveloped Areas of New Jersey Barrier Islands, March 9, 1991, to July 30, 2013

Assessing the physical change to shorelines and wetlands is critical for determining the resiliency of wetland systems that protect adjacent habitat and communities. The wetland and back-barrier shorelines of the New Jersey barrier islands were changed by wave action and storm surge from Hurricane Sandy in 2012. The U.S. Geological Survey Coastal and Marine Geology Program is assessing the impact of Hurricane Sandy to understand its historical context and the vulnerability of wetland systems. These assessments require data that document physical changes over time, such as maps, aerial photographs, satellite imagery, and lidar elevation data. This Data Series Report includes open-ocean shorelines, back-island shorelines, back-island shoreline points, sand polygons, and sand lines for the undeveloped areas of New Jersey barrier islands. These data were extracted from orthoimagery (aerial photography) taken between March 9, 1991, and July 30, 2013. The images used were 0.3–1-meter (m)-resolution U.S. Geological Survey Digital Orthophoto Quarter Quads (DOQQ), U.S. Department of Agriculture National Agriculture Imagery Program (NAIP) images, National Oceanic and Atmospheric Administration images , and New Jersey Geographic Information Network images. The back-island shorelines were hand-digitized at the intersects of the apparent back-island shoreline and transects spaced at 20-m intervals. The open-ocean shorelines were hand-digitized at the approximate still-water level, such as tide level, which was fit through the average position of waves and swash apparent on the beach. Hand-digitizing was done at a scale of approximately 1:2,000. The sand polygons were derived by an image-processing unsupervised classification technique that separates images into classes. The classes were then visually categorized as either sand or not sand. Sand lines were taken from the sand polygons. Also included in this report are 20-m-spaced transect lines and the transect base lines.

New Jersey↗
USGS1999

Delaware River Basin

During the past 25 years, industry and government have made large financial investments in manufacturing, processing, and wastewater-treatment facilities to reduce the amount of contaminants being discharged. Although these investments have led to improved water quality across the Nation, concerns about the effects of nutrients, toxins, and pathogens on human health and that of ecological communities remain. To address the need for consistent and scientifically sound information for managing the Nation's water resources, the U.S. Geological Survey began the National Water-Quality Assessment (NAWQA) program in 1991. This program is unique in that it integrates surface- and ground-water-quality monitoring with the study of aquatic ecosystems. The goals of the NAWQA program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers (water-bearing sediments and rocks), (2) describe how water quality is changing over time, and (3) increase our understanding of the natural and human factors that affect water quality (Leahy and others, 1990, Gilliom and others, 1995). Assessing the quality of water in every location of the Nation would not be practical. Therefore, NAWQA investigations are conducted within 59 selected areas called study units (fig. 1). These study units encompass important river and aquifer systems in the United States and represent the diverse geographic, waterresource, land-use, and water-use characteristics of the Nation. The Delaware River Basin is one of 15 study units in which work began in 1996. Water-quality sampling in the study unit will begin in 1999. This fact sheet provides a brief overview of the NAWQA program, describes the Delaware River Basin study unit, identifies the major water-quality issues in the basin, and documents the plan of study that will be followed during the study-unit investigation.

Delaware, Maryland, New Jersey, New York, Pennsylv↗
USGS2005

Distance to nearest road in the conterminous United States

The USGS Geographic Analysis and Monitoring (GAM) program has developed a national, high resolution dataset that gives the distance to the nearest road every 30 meters across the conterminous 48 states. This work provides the first unified national picture of roadless space, vehicular accessibility, and intensity of road construction. The new dataset is the first member of the National Overview Road Metrics (NORM) family of road related indicators. This indicator measures straight-line or Euclidean distance (ED) to the nearest road, and is given the compound name NORM ED. NORM ED data can be viewed and downloaded from the transportation section of the web viewer for The National Map , http://nationalmap.usgs.gov. The full-resolution dataset for the conterminous states is made of 8.7 billion values.

Fact Sheet↗
USGS2009

Hazards, Disasters, and The National Map

Federal, State, and local response and management personnel must have current, reliable, and easily accessible geographic information and maps to prepare for, respond to, or recover from emergency situations. In life-threatening events, such as earthquakes, floods, or wildland fires, geographic information is essential for locating critical infrastructure and carrying out evacuation and rescue operations. The USGS promotes partnerships to ensure that base map data are up to date, readily available, and shareable among local, state, and National users. The National Map enables other government agencies, private industry, and the public to link and share additional data that provide even more information. These efforts with state and local governments have helped standardize the data by reducing data inconsistencies between neighboring jurisdictions and will help fill in the gaps for those places where data are lacking.

Fact Sheet↗
USGS2004

Metadata for ReVA logistic regression dataset

The U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency's Regional Vulnerability Assessment Program, has developed a set of statistical tools to support regional-scale, ground-water quality and vulnerability assessments. The Regional Vulnerability Assessment Program goals are to develop and demonstrate approaches to comprehensive, regional-scale assessments that effectively inform water-resources managers and decision-makers as to the magnitude, extent, distribution, and uncertainty of current and anticipated environmental risks. The U.S. Geological Survey is developing and exploring the use of statistical probability models to characterize the relation between ground-water quality and geographic factors in the Mid-Atlantic Region. Available water-quality data obtained from U.S. Geological Survey National Water-Quality Assessment Program studies conducted in the Mid-Atlantic Region were used in association with geographic data (land cover, geology, soils, and others) to develop logistic-regression equations that use explanatory variables to predict the presence of a selected water-quality parameter exceeding specified management concentration thresholds. The resulting logistic-regression equations were transformed to determine the probability, P(X), of a water-quality parameter exceeding a specified management threshold. Additional statistical procedures modified by the U.S. Geological Survey were used to compare the observed values to model-predicted values at each sample point. In addition, procedures to evaluate the confidence of the model predictions and estimate the uncertainty of the probability value were developed and applied. The resulting logistic-regression models were applied to the Mid-Atlantic Region to predict the spatial probability of nitrate concentrations exceeding specified management thresholds. These thresholds are usually set or established by regulators or managers at national or local levels. At management thresholds of 1 milligram per liter, and 3 milligrams per liter, the probability of nitrate concentrations exceeding these levels is greater than 50 percent (.50) throughout much of the Mid-Atlantic Region. This includes extensive areas throughout central Maryland, southeastern Pennsylvania, northwestern Pennsylvania and the Delmarva Peninsula. In addition, extensive areas in North Carolina and Virginia also have high probabilities of nitrate concentrations in ground water exceeding management thresholds of 1 milligram per liter and 3 milligrams per liter. The mapped areas showing a high predicted probability of nitrate concentrations in ground water exceeding 1 milligram per liter and 3 milligrams per liter correspond to areas that are mapped as cultivated land cover overlying carbonate rocks. At a management threshold of 10 milligrams per liter (corresponding to the U.S. Environmental Protection Agency standard for nitrate in drinking water of 10 milligrams per liter), the predicted probability of nitrate concentrations in ground water exceeding this level are low for most of the Mid-Atlantic Region except for the Delmarva Peninsula, southeastern Pennsylvania, and areas mapped as carbonate rocks in Virginia, Maryland, and Pennsylvania.

Open-File Report↗
USGS2005

Ground-water vulnerability to nitrate contamination at multiple thresholds in the mid-Atlantic region using spatial probability models

The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency?s Regional Vulnerability Assessment Program, has developed a set of statistical tools to support regional-scale, ground-water quality and vulnerability assessments. The Regional Vulnerability Assessment Program?s goals are to develop and demonstrate approaches to comprehensive, regional-scale assessments that effectively inform managers and decision-makers as to the magnitude, extent, distribution, and uncertainty of current and anticipated environmental risks. The U.S. Geological Survey is developing and exploring the use of statistical probability models to characterize the relation between ground-water quality and geographic factors in the Mid-Atlantic Region. Available water-quality data obtained from U.S. Geological Survey National Water-Quality Assessment Program studies conducted in the Mid-Atlantic Region were used in association with geographic data (land cover, geology, soils, and others) to develop logistic-regression equations that use explanatory variables to predict the presence of a selected water-quality parameter exceeding a specified management concentration threshold. The resulting logistic-regression equations were transformed to determine the probability, P(X), of a water-quality parameter exceeding a specified management threshold. Additional statistical procedures modified by the U.S. Geological Survey were used to compare the observed values to model-predicted values at each sample point. In addition, procedures to evaluate the confidence of the model predictions and estimate the uncertainty of the probability value were developed and applied. The resulting logistic-regression models were applied to the Mid-Atlantic Region to predict the spatial probability of nitrate concentrations exceeding specified management thresholds. These thresholds are usually set or established by regulators or managers at National or local levels. At management thresholds of 1 milligram per liter and 3 milligrams per liter as nitrogen, the probability of nitrate concentrations exceeding these levels is greater than 50 percent (0.50) throughout much of the Mid-Atlantic Region. This includes extensive areas throughout central Maryland, southeastern Pennsylvania, northwestern Pennsylvania, and the Delmarva Peninsula. In addition, extensive areas in North Carolina and Virginia also have high probabilities of nitrate concentrations in ground water exceeding management thresholds of 1 milligram per liter and 3 milligrams per liter. The mapped areas showing a high predicted probability of nitrate concentrations in ground water exceeding 1 milligram per liter and 3 milligrams per liter correspond to areas that are mapped as cultivated land cover and/or overlying carbonate rocks. At a management threshold of 10 milligrams per liter (corresponding to the U.S. Environmental Protection Agency standard for nitrate in drinking water of 10 milligrams per liter), the predicted probability of nitrate concentrations in ground water exceeding this level is low for most of the Mid-Atlantic Region, except for the Delmarva Peninsula, southeastern Pennsylvania, and areas mapped as carbonate rocks in Virginia, Maryland, and Pennsylvania.

Scientific Investigations Report↗
USGS2013

Observed changes in phenology across the USA: A regional review for the 2013 National Climate Assessment, Northeast Regional Information Sheet

This is one in a series of eight, geographic region-focused information sheets that summarizes documented changes in plant and animal phenology over the past century across the United States. This summary is based on long-term studies (10 years or more) published in the primary scientific literature since 2001. A forthcoming manuscript synthesizes the findings of the eight regional information sheets. This information was developed in support of the U.S. Global Change Research Program’s National Climate Assessment and can be used to facilitate preparation for the cascading effects of ongoing climate change.

Connecticut, Delaware, Maine, Maryland, Massachuse↗
USGS2013

Observed changes in phenology across the USA: A regional review for the 2013 National Climate Assessment, Southwest Regional Information Sheet

This is one in a series of eight, geographic region-focused information sheets that summarizes documented changes in plant and animal phenology over the past century across the United States. This summary is based on long-term studies (10 years or more) published in the primary scientific literature since 2001. A forthcoming manuscript synthesizes the findings of the eight regional information sheets. This information was developed in support of the U.S. Global Change Research Program’s National Climate Assessment and can be used to facilitate preparation for the cascading effects of ongoing climate change.

Arizona, California, Colorado, Nevada, New Mexico,↗
USGS2013

Observed changes in phenology across the USA: A regional review for the 2013 National Climate Assessment, Midwest Regional Information Sheet

This is one in a series of eight, geographic region-focused information sheets that summarizes documented changes in plant and animal phenology over the past century across the United States. This summary is based on long-term studies (10 years or more) published in the primary scientific literature since 2001. A forthcoming manuscript synthesizes the findings of the eight regional information sheets. This information was developed in support of the U.S. Global Change Research Program’s National Climate Assessment and can be used to facilitate preparation for the cascading effects of ongoing climate change.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2013

Observed changes in phenology across the USA: A regional review for the 2013 National Climate Assessment, Southeast Regional Information Sheet

This is one in a series of eight, geographic region-focused information sheets that summarizes documented changes in plant and animal phenology over the past century across the United States. This summary is based on long-term studies (10 years or more) published in the primary scientific literature since 2001. A forthcoming manuscript synthesizes the findings of the eight regional information sheets. This information was developed in support of the U.S. Global Change Research Program’s National Climate Assessment and can be used to facilitate preparation for the cascading effects of ongoing climate change.

Alabama, Arkansas, Florida, Georgia, Kentucky, Lou↗
USGS2001

Alien plant invasion in mixed-grass prairie: Effects of vegetation type and anthropogenic disturbance

The ability of alien plant species to invade a region depends not only on attributes of the plant, but on characteristics of the habitat being invaded. Here, we examine characteristics that may influence the success of alien plant invasion in mixed-grass prairie at Theodore Roosevelt National Park, in western North Dakota, USA. The park consists of two geographically separate units with similar vegetation types and management history, which allowed us to examine the effects of native vegetation type, anthropogenic disturbance, and the separate park units on the invasion of native plant communities by alien plant species common to counties surrounding both park units. If matters of chance related to availability of propagules and transient establishment opportunities determine the success of invasion, park unit and anthropogenic disturbance should better explain the variation in alien plant frequency. If invasibility is more strongly related to biotic or physical characteristics of the native plant communities, models of alien plant occurrence should include vegetation type as an explanatory variable. We examined >1300 transects across all vegetation types in both units of the park. Akaike's Information Criterion (AIC) indicated that the fully parameterized model, including the interaction among vegetation type, disturbance, and park unit, best described the distribution of both total number of alien plants per transect and frequency of alien plants on transects where they occurred. Although all vegetation types were invaded by alien plants, mesic communities had both greater numbers and higher frequencies of alien plants than did drier communities. A strong element of stochasticity, reflected in differences in frequencies of individual species between the two park units, suggests that prediction of risk of invasion will always involve uncertainty. In addition, despite well-documented associations between anthropogenic disturbance and alien plant invasion, five of the six most abundant alien species at Theodore Roosevelt National Park had distributions unrelated to disturbance. We recommend that vegetation type be explicitly taken into account when designing monitoring plans for alien species in natural areas.

North Dakota↗