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USGS2014

Legacy data for a northern prairie grassland: Woodworth Study Area, North Dakota, 1963-89

Ecological data commonly become more valuable through time. Such legacy data provide baseline records of past biological, physical, and social information that provide historical perspective and are necessary for assessment of stasis or change. Legacy data collected at the Woodworth Study Area (WSA), a contiguous block of grasslands, croplands, and wetlands covering more than 1,000 hectares of the Prairie Pothole Region of North Dakota, are cataloged and summarized in this study. The WSA is one of the longest researched grassland sites in the Upper Midwest. It has an extensive history of settlement, land use, and management that provides a deeper context for future research. The WSA data include long-term vegetation transect records, land use history, habitat management records, geologic information, wetland hydrology and chemistry information, and spatial images. Substantial parts of these data have not been previously reported. The WSA is representative of many other lands purchased by the U.S. Fish and Wildlife Service in the Prairie Pothole Region from the 1930s to the 1970s; therefore, synthesized data from the WSA are broadly applicable to topics of concern in northern grasslands, such as increases in non-native plants, managing for biodiversity, and long-term effects of habitat management. New techniques are also described that were used to preserve these data for future analyses. The data preservation techniques are applicable to any project with data that should be preserved for 100 years or more.

North Dakota↗

USGS1979

Hydrocarbon geochemical analyses of Mid-Atlantic Outer Continental Shelf sediments: an environmental assessment

Concentration levels of hydrocarbon in 122 composite mid-Atlantic shelf surface sediment samples have been examined during the second year (1976-1977) of the Bureau of Land Management environmental assessment program. The objective of this study was to establish baseline concentrations and provide data for the "natural variability" curve for the mid-Atlantic region. Concentration levels ( μ g/g) have been determined for the total lipids recovered by liquid column chromatography, and hexane-soluble fraction (aliphatics) benzene fraction (aromatics) as resolved by gas chromatography for each composite sediment sample. Several geochemical parameter values were also determined among which were: 1) n-alkane odd-even ratio; 2) isoprenoid alkane/ n-alkane ratio; 3) pristine/phytane ratio; 4) pristane/n-C 17 ratio; and 5) phytane/n-C 18 ratio. Summary analyses of the concentrations and geochemical 18 parameters are included in this report. Surface sediments examined from the mid-Atlantic shelf contained very low concentrations of resolved aliphatic hydrocarbons, less than 5.0 μ g/gm sediment, and very low concentrations of resolved aromatic hydrocarbons, usually less than 1.0 μ g/gm sediment. Mass spectral analyses of selected hexane eluates confirmed the presence of a series of normal aliphatic alkanes ranging from to n-C 16 to n-C 31 as well as the isoprenoids pristane and phytane. A series of three hydrocarbon peaks in the n-C 20 to n-C 21 range were tentatively identified as n-C 25 unsaturated, branched homologs, The aromatic fractions contained a number of polynuclear aromatics including phenanthrenes, methylphenanthrenes, fluoranthene and pyrcne, benzofluoranthene, and alkyl benzenes. Data accumulated in the second year of the program, coupled with data from the first year's investigations (Miller et al., 1977), have provided the basis for establishing a preliminary natural. "variability curve" for the hydrocarbon concentration levels and distribution in these selected mid-Atlantic shelf samples. This curve shows the seasonal variability noted in both the aliphatic and aromatic hydrocarbons in these samples.

Mid-Atlantic Outer Continental Shelf↗

USGS1978

Hydrologic Unit Map-1978, state of South Dakota

This map and accompanying table show Hydrologic Unites that are basically hydrographic in nature. The Cataloging Unites shown supplant the Cataloging Units previously depicted n the 1974 State Hydrologic Unit Map. The boundaries as shown have been adapted from the 1974 State Hydrologic Unit Map, "The Catalog of Information on Water Data" (1972), "Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources" by the U.S. Water Resources Council (1970), "River Basin of the United States" by the U.S. Soil Conservation Service (1963, 1970), "River Basin Maps Showing Hydrologic Stations" by the Inter-Agency Committee on Water Resources, Subcommittee on Hydrology (1961), and State planning maps. The Political Subdivision has been adopted from "Counties and County Equivalents of the States if the United States" presented in Federal Information Processing Standards Publication 6-2, issued by the National Bureau of Standards (1973) in which each county or county equivalent is identified by a 2-character State code and a 3-character county code. The Regions, Subregions and Accounting Units are aggregates of the Cataloging Unites. The Regions and Sub regions are currently (1978) used by the U.S> Water Resources Council for comprehensive planning, including the National Assessment, and as a standard geographical framework for more detailed water and related land-resources planning. The Accounting Units are those currently (1978) in use by the U.S. Geological Survey for managing the National Water Data Network. This map was revised to include a boundary realinement between Cataloging Units 10140103 and 10160009.

South Dakota↗

USGS2011

U.S. Geological Survey 2011 assessment of undiscovered oil and gas resources of the Cook Inlet region, south-central Alaska

The U.S. Geological Survey (USGS) has completed an assessment of the volumes of undiscovered, technically recoverable oil and gas resources in conventional and continuous accumulations in Cook Inlet. The assessment used a geology-based methodology and results from new scientific research by the USGS and the State of Alaska, Department of Natural Resources, Division of Geological and Geophysical Surveys and Division of Oil and Gas (DOG). In the Cook Inlet region, the USGS estimates mean undiscovered volumes of nearly 600 million barrels of oil, about 19 trillion cubic feet of gas, and about 46 million barrels of natural gas liquids.

Open-File Report↗

USGS1997

Classification and Mapping of Agricultural Land for National Water-Quality Assessment

Agricultural land use is one of the most important influences on water quality at national and regional scales. Although there is great diversity in the character of agricultural land, variations follow regional patterns that are influenced by environmental setting and economics. These regional patterns can be characterized by the distribution of crops. A new approach to classifying and mapping agricultural land use for national water-quality assessment was developed by combining information on general land-use distribution with information on crop patterns from agricultural census data. Separate classification systems were developed for row crops and for orchards, vineyards, and nurseries. These two general categories of agricultural land are distinguished from each other in the land-use classification system used in the U.S. Geological Survey national Land Use and Land Cover database. Classification of cropland was based on the areal extent of crops harvested. The acreage of each crop in each county was divided by total row-crop area or total orchard, vineyard, and nursery area, as appropriate, thus normalizing the crop data and making the classification independent of total cropland area. The classification system was developed using simple percentage criteria to define combinations of 1 to 3 crops that account for 50 percent or more or harvested acreage in a county. The classification system consists of 21 level I categories and 46 level II subcategories for row crops, and 26 level I categories and 19 level II subcategories for orchards, vineyards, and nurseries. All counties in the United States with reported harvested acreage are classified in these categories. The distribution of agricultural land within each county, however, must be evaluated on the basis of general land-use data. This can be done at the national scale using 'Major Land Uses of the United States,' at the regional scale using data from the national Land Use and Land Cover database, or at smaller scales using locally available data.

Circular↗

USGS2013

Hurricane Isaac: observations and analysis of coastal change

Understanding storm-induced coastal change and forecasting these changes require knowledge of the physical processes associated with a storm and the geomorphology of the impacted coastline. The primary physical process of interest is sediment transport that is driven by waves, currents, and storm surge associated with storms. Storm surge, which is the rise in water level due to the wind, barometric pressure, and other factors, allows both waves and currents to impact parts of the coast not normally exposed to these processes. Coastal geomorphology reflects the coastal changes associated with extreme-storm processes. Relevant geomorphic variables that are observable before and after storms include sand dune elevation, beach width, shoreline position, sediment grain size, and foreshore beach slope. These variables, in addition to hydrodynamic processes, can be used to quantify coastal change and are used to predict coastal vulnerability to storms (Stockdon and others, 2007). The U.S. Geological Survey (USGS) National Assessment of Coastal Change Hazards (NACCH) project ( http://coastal.er.usgs.gov/national-assessment/ ) provides hazard information to those concerned about the Nation’s coastlines, including residents of coastal areas, government agencies responsible for coastal management, and coastal researchers. Extreme-storm research is a component of the NACCH project ( http://coastal.er.usgs.gov/hurricanes/ ) that includes development of predictive understanding, vulnerability assessments using models, and updated observations in response to specific storm events. In particular, observations were made to determine morphological changes associated with Hurricane Isaac, which made landfall in the United States first at Southwest Pass, at the mouth of the Mississippi River, at 0000 August 29, 2012 UTC (Coordinated Universal Time) and again, 8 hours later, west of Port Fourchon, Louisiana (Berg, 2013). Methods of observation included oblique aerial photography, airborne light detection and ranging (lidar) topographic surveys, and ground-based topographic surveys. This report documents data-collection efforts and presents qualitative and quantitative descriptions of hurricane-induced changes to the shoreline, beaches, dunes, and infrastructure in the region that was heavily impacted by Hurricane Isaac. The report is divided into the following sections: Section 1: Introduction Section 2: Storm Overview, presents a synopsis of the storm, including meteorological evolution, wind speed impact area, wind-wave generation, and storm-surge extent and magnitudes. Section 3: Coastal-Change Observations, describes data-collection missions, including acquisition of oblique aerial photography and airborne lidar topographic surveys, in response to Hurricane Isaac. Section 4: Coastal-Change Analysis, describes data-analysis methods and observations of coastal change.

Atlantic Ocean;Caribbean Sea;Gulf Of Mexico;Missis↗

USGS2018

Golden Eagle Monitoring Plan for the Desert Renewable Energy Conservation Plan

This report describes options for monitoring the status and population trends of the golden eagle (Aquila chrysaetos) within the Desert Renewable Energy Conservation Plan (DRECP) area of Southern California in maintaining stable or increasing population in the planning area. The report profiles the ecology of golden eagles in the region and provides a range of potential sampling options to address monitoring needs and objectives. This approach also focused on links between changes in human land-use, golden eagle nesting and foraging habitat conditions, and population dynamics. The report outlines how monitoring data from demographic, prey, and habitat studies were used to develop a predictive demographic model for golden eagles in the DRECP area. Results from the model simulations suggest increases in renewable energy development could have negative consequences for population trajectories. Results also suggest site-specific conservation actions could reduce the magnitude of negative impacts to the local population of eagles. A monitoring framework is proposed including: (1) annual assessments of site-occupancy and reproduction by territorial pairs of golden eagles (including rates at which sites become colonized or vacated over time); (2) estimates of survival, movements, and intensity of use of landscapes by breeding and non-breeding golden eagles; (3) periodic (conducted every two to four years) assessments of nesting and foraging habitats, prey populations, and associations with land-use and management activities; and (4) updating the predictive demographic model with new information obtained on eagles and associated population stressors. The results of this research were published in the Journal of Rapture Research, Wiens, David,Inman, Rich D., Esque, Todd C., Longshore, Kathleen M. and Nussear, Kenneth (2017). Spatial Demographic Models to Inform Conservation Planning of Golden Eagles in Renewable Energy Landscapes. 51(3):234-257.

Report↗

USGS2004

Water-Quality Assessment of the San Joaquin-Tulare Basins: Entering a new decade

In 1991, the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey began to address the need for consistent and scientifically sound information for managing the Nation's water resources. The long-term goals of this program are to assess the status of the quality of freshwater streams and aquifers, to describe trends or changes in water quality over time, and to provide a sound understanding of the natural and human factors that affect the quality of these resources (Hirsch and others, 1988). Investigations are being conducted within major river basins and aquifer systems, or 'study units,' throughout the Nation to provide a framework for national and regional water-quality assessments. In 2001, the NAWQA Program began its second decade of intensive water-quality assessments. Forty-two of the original 59 study units (reduced by elimination or combination) are being revisited (Gilliom and others, 2001). The San Joaquin-Tulare Basins study unit (fig. 1), located in central California, was a part of the first decadal cycle of the Program investigations and remains in the second cycle.

California↗

USGS2020

A within-season approach for detecting early crop stage of corn and soybean using high temporal and spatial resolution imagery

Crop emergence is a critical stage for crop development and crop growth modeling. Mapping crop emergence using remote sensing data is challenging. Previous remote sensing phenology algorithms showed that crop stages could be detected around the V3-V4 (3 to 4 established leaves) vegetative stage. Traditional approaches have a strong assumption regarding the temporal evolution of plant growth and normally require a complete growth period of observations to define seasonal changes. Most approaches were not designed for the within-season mapping in the early growing season. In the current paper, we developed a new within-season emergence (WISE) approach to mapping crop green-up date using satellite observations during early growth stages. The approach was first optimized using high spatiotemporal resolution (10 m, 2 day revisit) imagery from the Vegetation and Environment monitoring New MicroSatellite (VENµS) research mission, and assessed using ground observations of early crop growth stages (emergence VE and one leaf V1 stages for corn, and emergence VE and unifoliolate VC stages for soybeans) collected over the Beltsville Agricultural Research Center (BARC) experimental fields in Beltsville, MD during the 2019 growing season. Results show that early crop growth stages can be reliably detected at sub-field scale about two weeks after crop emergence. The remote sensing green-up dates were about 4-5 days after crop emergence on average. Coefficients of determination (R2) between green-up dates and the mid-point dates of the early growth stages were above 0.90. The mean absolute differences, standard deviations, and root mean square errors comparing to the early growth stage mid-point dates were within six days. The maximum differences were within ±10 days across all fields. The WISE approach was assessed using operational Sentinel-2 data (10 m, 5 day revisit) in BARC. The detected green-up dates from Sentinel-2 were found close to VENµS results. Some fields were not detected due to the lack of observations during emergence dates. For independent evaluation, the WISE approach was applied over an agricultural watershed on the Maryland Eastern Shore using both VENµS and the harmonized Landsat and Sentinel-2 (HLS) data (30 m, 3-4 day revisit). The green-up dates were compared with crop progress reports of crop emergence dates from the National Agricultural Statistics Service (NASS) at the state-level. The WISE -detected green-up dates at the regional scale are within VE stage ranges but slightly earlier than NASS crop progress reports at the state-level. The WISE approach uses remote sensing observations during the early crop growth stages and has potential for operational application within the season using Sentinel-2 and HLS data.

Maryland↗

USGS2013

Characterization of mercury contamination in the Androscoggin River, Coos County, New Hampshire

The former chloralkali facility in Berlin, New Hampshire, was designated a Superfund site in 2005. Historic paper mill activities resulted in the contamination of groundwater, surface water, and sediments with many organic compounds and mercury (Hg). Hg continues to seep into the Androscoggin River in elemental form through bedrock fractures. The objective of this study was to spatially characterize (1) the extent of Hg contamination in water, sediment, and biota; (2) Hg speciation and methylmercury (MeHg) production potential rates in sediment; (3) the availability of inorganic divalent Hg (Hg(II)) for Hg(II)-methylation (MeHg production); and (4) ancillary sediment geochemistry necessary to better understand Hg speciation and MeHg production potential rates in this system. Concentrations of total mercury (THg) and MeHg in sediment, pore water, and biota in the Androscoggin River were elevated downstream from the former chloralkali facility compared with those upstream from reference sites. Sequential extraction of surface sediment showed a distinct difference in Hg speciation upstream compared with downstream from the contamination site. An upstream site was dominated by potassium hydroxide-extractable forms (for example, organic-Hg or particle-bound Hg(II)), whereas sites downstream from the point source were dominated by more chemically recalcitrant forms (largely concentrated nitric acid-extractable), indicative of elemental mercury or mercurous chloride. At all sites, only a minor fraction (less than 0.1 percent) of THg existed in chemically labile forms (for example, water extractable or weak acid extractable). All metrics indicated that a greater percentage of mercury at an upstream site was available for Hg(II)-methylation compared with sites downstream from the point source, but the absolute concentration of bioavailable Hg(II) was greater downstream from the point source. In addition, the concentration of tin-reducible inorganic reactive mercury, a surrogate measure of bioavailable Hg(II) generally increased with distance downstream from the point source. Whereas concentrations of mercury species on a sediment-dry-weight basis generally reflected the relative location of the sample to the point source, river-reach integrated mercury-species inventories and MeHg production potential (MPP) rates reflected the amount of fine-grained sediment in a given reach. THg concentrations in biota were significantly higher downstream from the point source compared with upstream reference sites for smallmouth bass, white sucker, crayfish, oligochaetes, bat fur, nestling tree swallow blood and feathers, adult tree swallow blood, and tree swallow eggs. As with tin-reducible inorganic reactive mercury, THg in smallmouth bass also increased with distance downstream from the point source. Toxicity tests and invertebrate community assessments suggested that invertebrates were not impaired at the current (2009 and 2010) levels of mercury contamination downstream from the point source. Concentrations of THg and MeHg in most water and sediment samples from the Androscoggin River were below U.S. Environmental Protection Agency (USEPA), the Canadian Council of Ministers of the Environment, and probable effects level guidelines. Surface-water and sediment samples from the Androscoggin River had similar THg concentrations but lower MeHg concentrations compared with other rivers in the region. Concentrations of THg in fish tissue were all above regional and U.S. Environmental Protection Agency guidelines. Moreover, median THg concentrations in smallmouth bass from the Androscoggin River were significantly higher than those reported in regional surveys of river and streams nationwide and in the Northeastern United States and Canada. The higher concentrations of mercury in smallmouth bass suggest conditions may be more favorable for Hg(II)-methylation and bioaccumulation in the Androscoggin River compared with many other rivers in the United States and Canada.

New Hampshire↗

USGS1999

1999 Resource assessment of selected Tertiary coal beds and zones in the northern Rocky Mountains and Great Plains region

The USGS has assessed resources of selected coal of the Fort Union Formation and equivalent units in the Northern Rocky Mountains and Great Plains region. The assessment focused on coal in the Powder River, Williston, Hanna-Carbon, and Greater Green River basins most likely to be utilized in the next few decades. In other basins in the region Tertiary coal resources are summarized but not assessed. Disc 1, in PDF files, includes results of the assessment and chapters on coal geology, quantity and quality, and land use and ownership. Disc 2 provides GIS files for land use and ownership maps and geologic maps, and basic GIS data for the assessed basins. ArcView shapefiles, PDF files for cross sections and TIFF files are included along with ArcView Datapublisher software for Windows-based computer systems.

Colorado, Montana, Wyoming↗

USGS2014

Methods for estimating annual exceedance-probability discharges and largest recorded floods for unregulated streams in rural Missouri

Regression analysis techniques were used to develop a set of equations for rural ungaged stream sites for estimating discharges with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities, which are equivalent to annual flood-frequency recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively. Basin and climatic characteristics were computed using geographic information software and digital geospatial data. A total of 35 characteristics were computed for use in preliminary statewide and regional regression analyses. Annual exceedance-probability discharge estimates were computed for 278 streamgages by using the expected moments algorithm to fit a log-Pearson Type III distribution to the logarithms of annual peak discharges for each streamgage using annual peak-discharge data from water year 1844 to 2012. Low-outlier and historic information were incorporated into the annual exceedance-probability analyses, and a generalized multiple Grubbs-Beck test was used to detect potentially influential low floods. Annual peak flows less than a minimum recordable discharge at a streamgage were incorporated into the at-site station analyses. An updated regional skew coefficient was determined for the State of Missouri using Bayesian weighted least-squares/generalized least squares regression analyses. At-site skew estimates for 108 long-term streamgages with 30 or more years of record and the 35 basin characteristics defined for this study were used to estimate the regional variability in skew. However, a constant generalized-skew value of -0.30 and a mean square error of 0.14 were determined in this study. Previous flood studies indicated that the distinct physical features of the three physiographic provinces have a pronounced effect on the magnitude of flood peaks. Trends in the magnitudes of the residuals from preliminary statewide regression analyses from previous studies confirmed that regional analyses in this study were similar and related to three primary physiographic provinces. The final regional regression analyses resulted in three sets of equations. For Regions 1 and 2, the basin characteristics of drainage area and basin shape factor were statistically significant. For Region 3, because of the small amount of data from streamgages, only drainage area was statistically significant. Average standard errors of prediction ranged from 28.7 to 38.4 percent for flood region 1, 24.1 to 43.5 percent for flood region 2, and 25.8 to 30.5 percent for region 3. The regional regression equations are only applicable to stream sites in Missouri with flows not significantly affected by regulation, channelization, backwater, diversion, or urbanization. Basins with about 5 percent or less impervious area were considered to be rural. Applicability of the equations are limited to the basin characteristic values that range from 0.11 to 8,212.38 square miles (mi 2 ) and basin shape from 2.25 to 26.59 for Region 1, 0.17 to 4,008.92 mi 2 and basin shape 2.04 to 26.89 for Region 2, and 2.12 to 2,177.58 mi 2 for Region 3. Annual peak data from streamgages were used to qualitatively assess the largest floods recorded at streamgages in Missouri since the 1915 water year. Based on existing streamgage data, the 1983 flood event was the largest flood event on record since 1915. The next five largest flood events, in descending order, took place in 1993, 1973, 2008, 1994 and 1915. Since 1915, five of six of the largest floods on record occurred from 1973 to 2012.

Missouri↗

USGS2008

Porphyry copper deposits of the world: Database and grade and tonnage models, 2008

This report is an update of earlier publications about porphyry copper deposits (Singer, Berger, and Moring, 2002; Singer, D.A., Berger, V.I., and Moring, B.C., 2005). The update was necessary because of new information about substantial increases in resources in some deposits and because we revised locations of some deposits so that they are consistent with images in GoogleEarth. In this report we have added new porphyry copper deposits and removed a few incorrectly classed deposits. In addition, some errors have been corrected and a number of deposits have had some information, such as grades, tonnages, locations, or ages revised. Colleagues have helped identify places where improvements were needed. Mineral deposit models are important in exploration planning and quantitative resource assessments for a number of reasons including: (1) grades and tonnages among deposit types are significantly different, and (2) many types occur in different geologic settings that can be identified from geologic maps. Mineral deposit models are the keystone in combining the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Too few thoroughly explored mineral deposits are available in most local areas for reliable identification of the important geoscience variables or for robust estimation of undiscovered deposits?thus we need mineral-deposit models. Globally based deposit models allow recognition of important features because the global models demonstrate how common different features are. Well-designed and -constructed deposit models allow geologists to know from observed geologic environments the possible mineral deposit types that might exist, and allow economists to determine the possible economic viability of these resources in the region. Thus, mineral deposit models play the central role in transforming geoscience information to a form useful to policy makers. The foundation of mineral deposit models is information about known deposits. The purpose of this publication is to make this kind of information available in digital form for porphyry copper deposits. The consistently defined deposits in this file provide the foundation for grade and tonnage models included here and for mineral deposit density models (Singer and others, 2005: Singer, 2008).

Open-File Report↗

USGS2021

Climate change scenario planning for resource stewardship at Wind Cave National Park

This report explains scenario planning as a climate change adaptation tool in general, then describes how it was applied to Wind Cave National Park as the second part of a pilot project to dovetail climate change scenario planning with National Park Service (NPS) Resource Stewardship Strategy development. In the orientation phase, Park and regional NPS staff, other subject-matter experts, natural and cultural resource planners, and the climate change core team who led the scenario planning project identified priority resource management topics and associated climate sensitivities. Next, the climate change core team used this information to create a set of four divergent climate futures—summaries of relevant climate data from individual climate projections—to encompass the range of ways climate could change in coming decades in the park. Participants in the scenario planning workshop then developed climate futures into robust climate-resource scenarios that considered expert-elicited resource impacts and identified potential management responses. Finally, the scenario-based resource responses identified by park staff and subject matter experts were used to integrate climate-informed adaptations into resource stewardship goals and activities for the park's Resource Stewardship Strategy. This process of engaging resource managers in climate change scenario planning ensures that their management and planning decisions are informed by assessments of critical future climate uncertainties.

South Dakota↗

USGS2009

Data on mercury in water, bed sediment, and fish from streams across the United States, 1998-2005

The U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) and Toxic Substances Hydrology Programs conducted the National Mercury Pilot Study in 1998 to examine relations of mercury (Hg) in water, bed sediment and fish in streams across the United States, including Alaska and Hawaii. Water and bed-sediment samples were analyzed for total Hg (THg), methylmercury (MeHg), and other constituents; fish were analyzed for THg. Similar sampling was conducted at additional streams across the country in 2002 and 2004-05. This report summarizes sample collection and processing protocols, analytical methods, environmental data, and quality-assurance data for stream water, bed sediment, and fish for these national studies. To extend the geographic coverage of the data, this report also includes four regional USGS Hg studies conducted during 1998-2001 and 2004. The environmental data for these national and regional Hg studies are provided in an electronic format.

Data Series↗

USGS2012

Data resources for range-wide assessment of livestock grazing across the sagebrush biome

The data contained in this series were compiled, modified, and analyzed for the U.S. Geological Survey (USGS) report "Range-Wide Assessment of Livestock Grazing Across the Sagebrush Biome." This report can be accessed through the USGS Publications Warehouse (online linkage: http://pubs.usgs.gov/of/2011/1263/). The dataset contains spatial and tabular data related to Bureau of Land Management (BLM) Grazing Allotments. We reviewed the BLM national grazing allotment spatial dataset available from the GeoCommunicator National Integrated Land System (NILS) website in 2007 (http://www.geocommunicator.gov). We identified several limitations in those data and learned that some BLM State and/or field offices had updated their spatial data to rectify these limitations, but maintained the data outside of NILS. We contacted appropriate BLM offices (State or field, 25 in all) to obtain the most recent data, assessed the data, established a data development protocol, and compiled data into a topologically enforced dataset throughout the area of interest for this project (that is, the pre-settlement distribution of Greater Sage-Grouse in the Western United States). The final database includes three spatial datasets: Allotments (BLM Grazing Allotments), OUT_Polygons (nonallotment polygons used to ensure topology), and Duplicate_Polygon_Allotments. See Appendix 1 of the aforementioned report for complete methods. The tabular data presented here consists of information synthesized by the Land Health Standard (LHS) analysis (Appendix 2), and data obtained from the BLM Rangeland Administration System (http://www.blm.gov/ras/). In 2008, available LHS data for all allotments in all regions were compiled by BLM in response to a Freedom of Information Act (FOIA) request made by a private organization. The BLM provided us with a copy of these data. These data provided three major types of information that were of interest: (1) date(s) (if any) of the most recent LHS evaluation for each allotment; (2) whether if evaluated, each region-specific standard (3–8 LHS depending on region) had been met on a given allotment; and (3) whether livestock contributed to any of these standards not being met. A description of how we processed the original data to prepare for analysis is described in Appendix 2, and the synthesized dataset can be found in the table "lhs_x_walk." Permitted use dates, livestock type (horse, sheep or cattle), number of livestock, and Animal Unit Months [the number of animal units (1,000-pound animal equivalents) that can be grazed for 31 days with the available forage in a sustainable manner] are the legal maximum grazing amounts for a given allotment, and legal adjustments to these numbers occur infrequently. We summarized permitted use by BLM allotment in the table "Permitted_Use." Billed use records are used for calculations of permittees' annual grazing bills. We summarized billed use by allotment for BLM grazing year in the table "Billed_Use." All three tables can be joined with the allotment spatial data in a geographic information system (GIS) environment, using the IDENT attribute as the primary key.

Data Series↗

USGS2001

Subsurface correlations and sequence stratigraphic interpretations of lower Silurian strata in the Appalachian Basin of northeast Ohio, southwest New York, and northwest Pennsylvania

Significant quantities of recoverable natural gas resources are estimated to be in the regionally extensive Lower Silurian Medina Group and “Clinton” sandstone of the Appalachian Basin (Gautier and others, 1995; Ryder and others, 1996; Ryder, 1998). In order to assess these accumulations of natural gas more accurately, the U.S. Geological Survey (USGS) has investigated the Silurian stratigraphy along six lines of cross section located in New York, Pennsylvania, Ohio, and West Virginia (fig. 1). Cross section A–A' extends about 375 mi from northeast to southwest and is oriented approximately parallel to the nearby paleoshoreline of the Silurian epeiric sea. The remaining cross sections extend about 100–200 mi from northwest to southeast and are oriented nearly perpendicular to the paleoshoreline. Stratigraphic investigations along A–A' were reported by Ryder (2000), correlations along D–D' were reported by Keighin (1998), and investigations along E–E' and F–F' were in progress at the time of this publication. This report provides correlations for Silurian strata along cross sections B–B' and C–C', which are located in the northern part of the Appalachian Basin (figs. 1 and 2). Cross section B–B' extends about 140 mi from Chautauqua County, N.Y., to Clinton County, Pa., and C–C' extends about 200 mi from Lake County, Ohio, to Clinton County, Pa. Correlations are made along B–B' and C–C' for the Lower Silurian Medina and Clinton Groups, Lower Silurian Tuscarora and Rose Hill Formations, and Lower and Upper Silurian Lockport Group and Mifflintown Formation (lower part). Emphasis is placed on the Medina Group because it is the principal natural gas reservoir in the Silurian deposit.

Ohio, Pennsylvania↗

USGS1984

Design of a ground-water-quality monitoring network for the Salinas River basin, California

A regional ground-water quality monitoring network for the entire Salinas River drainage basin was designed to meet the needs of the California State Water Resources Control Board. The project included phase 1--identifying monitoring networks that exist in the region; phase 2--collecting information about the wells in each network; and phase 3--studying the factors--such as geology, land use, hydrology, and geohydrology--that influence the ground-water quality, and designing a regional network. This report is the major product of phase 3. Based on the authors ' understanding of the ground-water-quality monitoring system and input from local offices, an ideal network was designed. The proposed network includes 317 wells and 8 stream-gaging stations. Because limited funds are available to implement the monitoring network, the proposed network is designed to correspond to the ideal network insofar as practicable, and is composed mainly of 214 wells that are already being monitored by a local agency. In areas where network wells are not available, arrangements will be made to add wells to local networks. The data collected by this network will be used to assess the ground-water quality of the entire Salinas River drainage basin. After 2 years of data are collected, the network will be evaluated to test whether it is meeting the network objectives. Subsequent network evaluations will be done very 5 years. (USGS)

Water-Resources Investigations Report↗