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Mining Claim Activity on Federal Land in the United States

Several statistical compilations of mining claim activity on Federal land derived from the Bureau of Land Management's LR2000 database have previously been published by the U.S Geological Survey (USGS). The work in the 1990s did not include Arkansas or Florida. None of the previous reports included Alaska because it is stored in a separate database (Alaska Land Information System) and is in a different format. This report includes data for all states for which there are Federal mining claim records, beginning in 1976 and continuing to the present. The intent is to update the spatial and statistical data associated with this report on an annual basis, beginning with 2005 data. The statistics compiled from the databases are counts of the number of active mining claims in a section of land each year from 1976 to the present for all states within the United States. Claim statistics are subset by lode and placer types, as well as a dataset summarizing all claims including mill site and tunnel site claims. One table presents data by case type, case status, and number of claims in a section. This report includes a spatial database for each state in which mining claims were recorded, except North Dakota, which only has had two claims. A field is present that allows the statistical data to be joined to the spatial databases so that spatial displays and analysis can be done by using appropriate geographic information system (GIS) software. The data show how mining claim activity has changed in intensity, space, and time. Variations can be examined on a state, as well as a national level. The data are tied to a section of land, approximately 640 acres, which allows it to be used at regional, as well as local scale. The data only pertain to Federal land and mineral estate that was open to mining claim location at the time the claims were staked.

Data Series

Archive of side scan sonar and bathymetry data collected during USGS Cruise 06FSH01 offshore of Siesta Key, Florida, May 2006

This DVD publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.

Florida

Drought-trigger ground-water levels in Chester County, Pennsylvania, for the period of record ending May 2006

This report presents the results of a study by the U.S. Geological Survey (USGS), in cooperation with the Chester County Water Resources Authority (CCWRA), to update the drought-trigger water levels for the Chester County observation-well network. The Chester County observation-well network was established in 1973 through a cooperative agreement between the CCWRA and the USGS to monitor local ground-water levels and trends and to determine drought conditions. In 1990 and again in 1997, drought-warning and drought-emergency water-level triggers were determined for the majority of wells in the existing Chester County observation-well network of 23 wells. Since 1997, the Chester County observation-well network expanded to 29 wells, some of the original wells were destroyed, and additional monthly water-level observations were made to allow for better statistical relations. Because of these changes, new statistics for water-level triggers were required. For this study, 19 of the 29 wells in the observation-well network were used to compute drought-trigger water levels. An additional 'drought-watch water-level trigger' category was developed to make the Chester County drought-trigger water-level categories consistent with those implemented by the Pennsylvania Department of Environmental Protection (PaDEP). The three drought-trigger water-level categories, as defined by PaDEP are 1) 'drought watch' when at the 75th-percentile level; 2) 'drought warning' when at the 90th-percentile level; and 3) 'drought emergency' when at the 95th-percentile level. A revised methodology, resulting from longer periods of record representing ground-water and climatic conditions and changes in local water use, has resulted in some observed differences in drought-trigger water levels. A comparison of current drought-trigger water levels to those calculated in 1997 shows the largest mean annual change in percentile values was in northeastern Chester County. In this northeastern region, the average 90th-percentile water levels changed by as much as 1.84 feet (17.5 percent) from those determined in 1997. Other observation wells in the county generally exhibited a smaller mean annual change in percentile values; a typical change was less than 0.5 foot. While most revisions in the drought-trigger water levels generally can be attributed to different methodology and (or) the additional years of data collected under existing climatic conditions, anthropogenic influences, such as the cessation of local pumping stresses, also were shown to cause changes in the drought-trigger water levels determined in this study.

Pennsylvania

Monitoring the storm tide of Hurricane Wilma in southwestern Florida, October 2005

Temporary monitoring stations employing non-vented pressure transducers were used to augment an existing U.S. Geological Survey coastal monitoring network to document the inland water levels related to the storm tide of Hurricane Wilma on the southwestern coast of Florida. On October 22, 2005, an experimental network consisting of 30 temporary stations was deployed over 90 miles of coastline to record the magnitude, extent, and timing of hurricane storm tide and coastal flooding. Sensors were programmed to record time, temperature, and barometric or water pressure. Water pressure was adjusted for changes in barometric pressure and salinity, and then converted to feet of water above the sensor. Elevation surveys using optical levels were conducted to reference storm tide water-level data and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). Storm tide water levels more than 5 feet above NAVD 88 were recorded by sensors at several locations along the southwestern Florida coast. Temporary storm tide monitoring stations used for this effort have demonstrated their value in: (1) furthering the understanding of storm tide by allowing the U.S. Geological Survey to extend the scope of data collection beyond that of existing networks, and (2) serving as backup data collection at existing monitoring stations by utilizing nearby structures that are more likely to survive a major hurricane.

Florida

Archive of digital and digitized analog boomer seismic reflection data collected during USGS cruise 96CCT02 in Copano, Corpus Christi, and Nueces Bays and Corpus Christi Bayou, Texas, July 1996

In June of 1996, the U.S. Geological Survey conducted geophysical surveys from Nueces to Copano Bays, Texas. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, GIS information, cruise log, and formal FGDC metadata. Filtered and gained digital images of the seismic profiles and high resolution scanned TIFF images of the original paper printouts are also provided. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG-Y files (Zihlman, 1992) are also provided.

Texas

Digitally available interval-specific rock-sample data compiled from historical records, Nevada National Security Site and vicinity, Nye County, Nevada

Between 1951 and 1992, 828 underground tests were conducted on the Nevada National Security Site, Nye County, Nevada. Prior to and following these nuclear tests, holes were drilled and mined to collect rock samples. These samples are organized and stored by depth of borehole or drift at the U.S. Geological Survey Core Library and Data Center at Mercury, Nevada, on the Nevada National Security Site. From these rock samples, rock properties were analyzed and interpreted and compiled into project files and in published reports that are maintained at the Core Library and at the U.S. Geological Survey office in Henderson, Nevada. These rock-sample data include lithologic descriptions, physical and mechanical properties, and fracture characteristics. Hydraulic properties also were compiled from holes completed in the water table. Rock samples are irreplaceable because pre-test, in-place conditions cannot be recreated and samples can not be recollected from the many holes destroyed by testing. Documenting these data in a published report will ensure availability for future investigators.

Nevada

Major- and Trace-Element Concentrations in Soils from Two Geochemical Surveys (1972 and 2005) of the Denver, Colorado, Metropolitan Area

Introduction This report contains major- and trace-element concentration data for soil samples collected in 1972 and 2005 from the Denver, Colorado, metropolitan area. A total of 405 sites were sampled in the 1972 study from an area approximately bounded by the suburbs of Golden, Thornton, Aurora, and Littleton to the west, north, east, and south, respectively. This data set included 34 duplicate samples collected in the immediate vicinity of the primary sample. In 2005, a total of 464 sites together with 34 duplicates were sampled from the same approximate localities sampled in 1972 as well as additional sites in east Aurora and the area surrounding the Rocky Mountain Arsenal. Sample density for both surveys was on the order of 1 site per square mile. At each site, sample material was collected from a depth of 0-5 inches. Each sample collected was analyzed for near-total major- and trace-element composition by the following methods: (1) inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) for aluminum, antimony, arsenic, barium, beryllium, bismuth, cadmium, calcium, cerium, cesium, chromium, cobalt, copper, gallium, indium, iron, lanthanum, lead, lithium, magnesium, manganese, molybdenum, nickel, niobium, phosphorus, potassium, rubidium, scandium, silver, sodium, strontium, sulfur, tellurium, thallium, thorium, tin, titanium, tungsten, uranium, vanadium, yttrium, and zinc; and (2) hydride generation-atomic absorption spectrometry for selenium. The samples collected in 2005 were also analyzed by a cold vapor-atomic absorption method for mercury. This report makes available the analytical results of these studies.

Data Series

1995 National Assessment of United States oil and gas resources: Results, methodology, and supporting data

This revised CD-ROM summarizes the results, released in 1995, of the 3-year study of the oil and gas resources of the onshore and state waters of the United States. Minor errors in the original DDS-30 (listed in DDS-35 and DDS-36) are corrected in this revised version and in the data files now released in DDS-35 and DDS-36. Estimates are made of technically recoverable oil, including measured (proved) reserves, future additions to reserves in existing fields, and undiscovered resources. Estimates are also made of the technically recoverable conventional resources of natural gas in measured reserves, in anticipated growth of reserves in existing fields, and in undiscovered resources. Additionally, an assessment is made of recoverable resources in continuous-type (largely unconventional) accumulations in sandstones, shales, chalks, and coal beds.

Data Series

Concentrations of selected pharmaceuticals and antibiotics in south-central Pennsylvania waters, March through September 2006

This report presents environmental and quality-control data from analyses of 15 pharmaceutical and 31 antibiotic compounds in water samples from streams and wells in south-central Pennsylvania. The analyses are part of a study by the U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Environmental Protection (PADEP) to define concentrations of selected emerging contaminants in streams and well water in Pennsylvania. Sampling was conducted at 11 stream sites and at 6 wells in 9 counties of south-central Pennsylvania. Five of the streams received municipal wastewater and 6 of the streams received runoff from agricultural areas dominated by animal-feeding operations. For all 11 streams, samples were collected at locations upstream and downstream of the municipal effluents or animal-feeding operations. All six wells were in agricultural settings. A total of 120 environmental samples and 21 quality-control samples were analyzed for the study. Samples were collected at each site in March/April, May, July, and September 2006 to obtain information on changes in concentration that could be related to seasonal use of compounds. For streams, 13 pharmaceuticals and 11 antibiotics were detected at least 1 time. Detections included analytical results that were estimated or above the minimum reporting limits. Seventy-eight percent of all detections were analyzed in samples collected downstream from municipal-wastewater effluents. For streams receiving wastewater effluents, the pharmaceuticals caffeine and para-xanthine (a degradation product of caffeine) had the greatest concentrations, 4.75 μg/L (micrograms per liter) and 0.853 μg/L, respectively. Other pharmaceuticals and their respective maximum concentrations were carbamazepine (0.516 μg/L) and ibuprofen (0.277 μg/L). For streams receiving wastewater effluents, the antibiotic azithromycin had the greatest concentration (1.65 μg/L), followed by sulfamethoxazole (1.34 μg/L), ofloxacin (0.329 μg/L), and trimethoprim (0.256 μg/L). For streams receiving runoff from animal-feeding operations, the only pharmaceuticals detected were acetaminophen, caffeine, cotinine, diphenhydramine, and carbamazepine. The maximum concentration for pharmaceuticals was 0.053 μg/L. Three streams receiving runoff from animal-feeding operations had detections of one or more antibiotic compound--oxytetracycline, sulfadimethoxine, sulfamethoxazole, and tylosin. The maximum concentration for antibiotics was 0.157 μg/L. The average number of compounds (pharmaceuticals and antibiotics) detected in sites downstream from animal-feeding operations was three. The average number of compounds detected downstream from municipal-wastewater effluents was 13. For wells used to supply livestock, four compounds were detected--two pharmaceuticals (cotinine and diphenhydramine) and two antibiotics (tylosin and sulfamethoxazole). There were five detections in all the well samples. The maximum concentration detected in well water was for cotinine, estimated to be 0.024 μg/L. Seasonal occurrence of pharmaceutical and antibiotic compounds in stream water varied by compound and site type. At four stream sites, the same compounds were detected in all four seasonal samples. At other sites, pharmaceutical or antibiotic compounds were detected only one time in seasonal samples. Winter samples collected in streams receiving municipalwastewater effluent had the greatest number of compounds detected (21). Research analytical methods were used to determine concentrations for pharmaceuticals and antibiotics. To assist in evaluating the quality of the analyses, detailed information is presented on laboratory methodology and results from qualitycontrol samples. Quality-control data include results for nine blanks, nine duplicate environmental sample pairs, and three laboratory-spiked environmental samples as well as the recoveries of compounds in laboratory surrogates and laboratory reagent spikes.

Pennsylvania

Ground-water quality data in the Southern Sierra study unit, 2006— Results from the California GAMA program

Ground-water quality in the approximately 1,800 square-mile Southern Sierra study unit (SOSA) was investigated in June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Southern Sierra study was designed to provide a spatially unbiased assessment of raw ground-water quality within SOSA, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from fifty wells in Kern and Tulare Counties. Thirty-five of the wells were selected using a randomized grid-based method to provide statistical representation of the study area, and fifteen were selected to evaluate changes in water chemistry along ground-water flow paths. The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, pharmaceutical compounds, and wastewater-indicator compounds], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3-trichloropropane (1,2,3-TCP)], naturally occurring inorganic constituents [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water], and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected for approximately one-eighth of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control information resulted in censoring of less than 0.2 percent of the data collected for ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. VOCs and pesticides were detected in less than one-third of the grid wells, and all detections in samples from SOSA wells were below health-based thresholds. All detections of trace elements and nutrients in samples from SOSA wells were below health-based thresholds, with the exception of four detections of arsenic that were above the USEPA maximum contaminant level (MCL-US) and one detection of boron that was above the CDPH notification level (NL-CA). All detections of radioactive constituents were below health-based thresholds, although four samples had activities of radon-222 above the proposed MCL-US. Most of the samples from SOSA wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic concerns. A few samples contained iron, manganese, or total dissolved solids at concentrations above the SMCL-CA thresholds.

California

Geospatial database of ground-water altitude and depth-to-ground-water data for Utah, 1971-2000

A geospatial database of ground-water-level altitude and depth-to-ground-water data for Utah was developed. Water-level contours from selected published reports were converted to digital Geographic Information System format and attributes describing the contours were added. Water-level altitude values were input to an inverse distance weighted interpolator to create a raster of interpolated water-level altitude for each report. The water-level altitude raster was subtracted from digital land-surface altitude data to obtain depth-to-water rasters for each study. Comparison of the interpolated rasters to actual water-level measurements shows that the interpolated water-level altitudes are well correlated with measured water-level altitudes from the same time period. The data can be downloaded and displayed in any Geographic Information System or can be explored by downloading a data package and map from the U.S. Geological Survey.

Utah

Supplemental materials for the analysis of capture-recapture data for polar bears in Western Hudson Bay, Canada, 1984-2004

Regehr and others (2007, Survival and population size of polar bears in western Hudson Bay in relation to earlier sea ice breakup: Journal of Wildlife Management, v. 71, no. 8) evaluated survival in relation to climatic conditions and estimated population size for polar bears (Ursus maritimus) in western Hudson Bay, Canada. Here, we provide supplemental materials for the analyses in Regehr and others (2007). We demonstrate how tag-return data from harvested polar bears were used to adjust estimates of total survival for human-caused mortality. We describe the sex and age composition of the capture and harvest samples and provide results for goodness-of-fit tests applied to capture-recapture models. We also describe the capture-recapture model selection procedure and the structure of the most supported model, which was used to estimate survival and population size.

Data Series

Water-Quality Data Collected from Vallecito Reservoir, Its Inflows and Outflow, Southwestern Colorado, 1999-2002

The Pine River Watershed Stakeholders Group was created in December 1997 to allow local participation in addressing water-quality issues in Los Pi?os River watershed, including Vallecito Reservoir in southwestern Colorado. One water-quality issue identified by the stakeholder group is to increase the understanding of the current water quality of Vallecito Reservoir, its two major inflows, and its outflow. The U.S. Geological Survey (USGS), in cooperation with volunteers from the Pine River Watershed Stakeholders Group and the U.S. Environmental Protection Agency (USEPA), U.S. Bureau of Reclamation (BOR), Colorado Department of Public Health and Environment (CDPHE), Pine River Irrigation District, Southern Ute Tribe, San Juan Basin Health Department, and San Juan Resource Conservation and Development, collected water-quality samples from Vallecito Reservoir, its two major inflows, and its outflow between August 1999 and November 2002 at about monthly intervals from April through November. The water-quality samples were analyzed for total and dissolved metals (aluminum, arsenic, cadmium, copper, chromium, iron, lead, manganese, mercury, nickel, silver, and zinc), dissolved major ions (calcium, magnesium, sodium, potassium, chloride, bicarbonate, and sulfate), dissolved silica, dissolved organic carbon (DOC), ultraviolet (UV) absorbance at 254 and 280 nanometers, nutrients (total organic nitrogen, dissolved organic nitrogen, dissolved ammonia, dissolved nitrate, total phosphorus, dissolved phosphorus, and orthophosphate), chlorophyll-a (reservoir only), and suspended sediment (inlets to the reservoir only). Measurements of field properties (pH, specific conductance, water temperature, and dissolved oxygen) were also made at each sampling site each time a water-quality sample was collected. This report documents (1) sampling sites and times of sample collection, (2) sample-collection methods, (3) laboratory analytical methods, and (4) responsibilities of each agency/group involved in the project. The report also provides the environmental and quality-control data collected during the project and provides an interpretation of the quality-control data (field blanks and field duplicates) to assess the quality of the environmental data. This report provides a baseline data set against which future changes in water quality can be assessed.

Data Series

Riparian Land Use/Land Cover Data for Five Study Units in the Nutrient Enrichment Effects Topical Study of the National Water-Quality Assessment Program

This dataset was developed as part of the National Water-Quality Assessment (NAWQA) Program, Nutrient Enrichment Effects Topical (NEET) study for five study units distributed across the United States: Apalachicola-Chattahoochee-Flint River Basin, Central Columbia Plateau-Yakima River Basin, Central Nebraska Basins, Potomac River Basin and Delmarva Peninsula, and White, Great and Little Miami River Basins. One hundred forty-three stream reaches were examined as part of the NEET study conducted 2003-04. Stream segments, with lengths equal to the logarithm of the basin area, were delineated upstream from the downstream ends of the stream reaches with the use of digital orthophoto quarter quadrangles (DOQQ) or selected from the high-resolution National Hydrography Dataset (NHD). Use of the NHD was necessary when the stream was not distinguishable in the DOQQ because of dense tree canopy. The analysis area for each stream segment was defined by a buffer beginning at the segment extending to 250 meters lateral to the stream segment. Delineation of land use/land cover (LULC) map units within stream segment buffers was conducted using on-screen digitizing of riparian LULC classes interpreted from the DOQQ. LULC units were mapped using a classification strategy consisting of nine classes. National Wetlands Inventory (NWI) data were used to aid in wetland classification. Longitudinal transect sampling lines offset from the stream segments were generated and partitioned into the underlying LULC types. These longitudinal samples yielded the relative linear extent and sequence of each LULC type within the riparian zone at the segment scale. The resulting areal and linear LULC data filled in the spatial-scale gap between the 30-meter resolution of the National Land Cover Dataset and the reach-level habitat assessment data collected onsite routinely for NAWQA ecological sampling. The final data consisted of 12 geospatial datasets: LULC within 25 meters of the stream reach (polygon); LULC within 50 meters of the stream reach (polygon); LULC within 50 meters of the stream segment (polygon); LULC within 100 meters of the stream segment (polygon); LULC within 150 meters of the stream segment (polygon); LULC within 250 meters of the stream segment (polygon); frequency of gaps in woody vegetation LULC at the reach scale (arc); stream reaches (arc); longitudinal LULC at the reach scale (arc); frequency of gaps in woody vegetation LULC at the segment scale (arc); stream segments (arc); and longitudinal LULC at the segment scale (arc).

Data Series

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

Archive of digital boomer and CHIRP seismic reflection data collected during USGS cruise 06FSH03 offshore of Fort Lauderdale, Florida, September 2006

In September of 2006, the U.S. Geological Survey conducted geophysical surveys offshore of Fort Lauderdale, FL. This report serves as an archive of unprocessed digital boomer and CHIRP seismic reflection data, trackline maps, navigation files, GIS information, Field Activity Collection System (FACS) logs, observer's logbook, and formal FGDC metadata. Filtered and gained digital images of the seismic profiles are also provided. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG-Y files (Zihlman, 1992) are also provided.

Florida

Trace-Element Concentrations in Tissues of Aquatic Organisms from Rivers and Streams of the United States, 1992-1999

The U.S. Geological Survey National Water-Quality Assessment Program collected tissue samples from a variety of aquatic organisms during 1992-1999 within 47 study units across the United States. These tissue samples were collected to determine the occurrence and distribution of 20 major and minor trace elements in aquatic organisms. This report presents the tissue trace-element concentration data, sample summaries, and concentration statistics for 1,457 tissue samples representing 76 species or groups of fish, aquatic invertebrates, and plants were collected at 824 sampling sites.

Data Series

1995 National assessment of United States oil and gas resources; results, methodology, and supporting data

This report summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States by the U.S. Geological Survey. A parallel study of the Federal offshore is being conducted by the Minerals Management Service. Estimates are made of technically recoverable oil, including measured (proved) reserves, future additions to reserves in existing fields, and undiscovered resources. Estimates are also made of the technically recoverable conventional resources of natural gas in measured reserves, in anticipated growth of reserves in existing fields, and in undiscovered resources. Additionally, an assessment is made of recoverable resources in continuous-type (largely unconventional) accumulations in sandstones, shales, chalks, and coal beds.

Data Series