Metadata: Identification_Information: Citation: Citation_Information: Originator: USGS; Eastern Energy Resource Team; Susan J. Tewalt Publication_Date: 1997 Title: Map showing structure contours and overburden thickness isopleths of the Pittsburgh Coal Bed in Pennsylvania, Ohio, West Virginia, and Maryland Series_Information: Series_Name: USGS Open-File Report Issue_Identification: 97-864, scale 1:425,000, two sheets Publication_Information: Publication_Place: Reston, VA Publisher: USGS; Eastern Energy Resources Description: Abstract: This dataset is a polygon coverage of the elevation of the top of the Pittsburgh Coal bed main bench, in feet above MSL. It was produced by gridding (producing 300 meter cells) 7,101 point-source data mainly from the National Coal Resources Data System (NCRDS) of the USGS, using ISM (Version 7.1) software. Grid was subsequently contoured in 50-foot intervals and imported to ARC/INFO. The elevation_st item for each polygon reflects a value halfway between the bounding contour lines. Coverage name: c9024st (024 is the bed code assigned to the Pittsburgh Coal bed). The coverage has been clipped to known resource areas that are being assessed in region 9 (the Appalachian basin) for the Pittsburgh coal bed. The coverage is published as Sheet 1 of the above-mentioned reference. Purpose: This dataset was used in the National Coal Resource Assessment Program to produce a generalized overburden thickness map, which was used in the regional evaluation of resources for the Pittsburgh coal bed in Region 9, the Appalachian basin. The dataset is useful for regional studies - not applicable to local scales. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1970's Ending_Date: 1997 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -82.657 East_Bounding_Coordinate: -78.604 North_Bounding_Coordinate: 40.635 South_Bounding_Coordinate: 38.315 Keywords: Theme: Theme_Keyword_Thesaurus: Coal Resource Classification of the U.S. Geological Survey, USGS Circular 891. Theme_Keyword: coal Theme_Keyword: coal resources Theme_Keyword: coal overburden Theme_Keyword: bituminous Theme_Keyword: geologic structure Theme_Keyword: outcrop Theme_Keyword: USGS Theme_Keyword: West Virginia Geological and Economic Survey Theme_Keyword: Ohio Division of Geological Survey Theme_Keyword: Maryland Geological Survey Theme_Keyword: Pennsylvania Bureau of Topographic and Geologic Survey Place: Place_Keyword_Thesaurus: Geographic Names Information System Place_Keyword: Appalachians Place_Keyword: CLAY County WV Place_Keyword: RITCHIE County WV Place_Keyword: MUSKINGUM County OH Place_Keyword: MONROE County OH Place_Keyword: WETZEL County WV Place_Keyword: TYLER County WV Place_Keyword: MARION County WV Place_Keyword: MONONGALIA County WV Place_Keyword: GREENE County PA Place_Keyword: BROOKE County WV Place_Keyword: TAYLOR County WV Place_Keyword: KANAWHA County WV Place_Keyword: LINCOLN County WV Place_Keyword: WAYNE County WV Place_Keyword: TUCKER County WV Place_Keyword: GRANT County WV Place_Keyword: MINERAL County WV Place_Keyword: GARRETT County MD Place_Keyword: SOMERSET County PA Place_Keyword: CAMBRIA County PA Place_Keyword: PRESTON County WV Place_Keyword: FAYETTE County PA Place_Keyword: BARBOUR County WV Place_Keyword: UPSHUR County WV Place_Keyword: BRAXTON County WV Place_Keyword: CABELL County WV Place_Keyword: LAWRENCE County OH Place_Keyword: GALLIA County OH Place_Keyword: MASON County WV Place_Keyword: PUTNAM County WV Place_Keyword: JACKSON County WV Place_Keyword: MEIGS County OH Place_Keyword: ROANE County WV Place_Keyword: WIRT County WV Place_Keyword: CALHOUN County WV Place_Keyword: ATHENS County OH Place_Keyword: WASHINGTON County OH Place_Keyword: WOOD County WV Place_Keyword: PLEASANTS County WV Place_Keyword: GILMER County WV Place_Keyword: DODDRIDGE County WV Place_Keyword: MORGAN County OH Place_Keyword: HARRISON County WV Place_Keyword: NOBLE County OH Place_Keyword: GUERNSEY County OH Place_Keyword: BELMONT County OH Place_Keyword: OHIO County WV Place_Keyword: HARRISON County OH Place_Keyword: CARROLL County OH Place_Keyword: JEFFERSON County OH Place_Keyword: MARSHALL County WV Place_Keyword: BEAVER County PA Place_Keyword: ALLEGHENY County PA Place_Keyword: ARMSTRONG County PA Place_Keyword: INDIANA County PA Place_Keyword: WESTMORELAND County PA Place_Keyword: ALLEGANY County MD Place_Keyword: LEWIS County WV Place_Keyword: HANCOCK County WV Place_Keyword: WASHINGTON County PA Stratum: Stratum_Keyword_Thesaurus: Geologic Names Unit Lexicon (GNULEX), 1996; Stratigraphic Nomenclature Databases for the United States, It's possessions, and Territories, U.S. Geological Survey Digital Data Series DDS-6, release 3. Stratum_Keyword: Pittsburgh coal bed horizon Stratum_Keyword: Pittsburgh coal Stratum_Keyword: Upper Pennsylvanian Stratum_Keyword: Monongahela Group Stratum_Keyword: Conemaugh Group Access_Constraints: none Use_Constraints: none Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Susan J. Tewalt Contact_Address: Address_Type: mailing address Address: MS 956 National Center City: Reston State_or_Province: Virginia Postal_Code: 20192 Country: USA Contact_Voice_Telephone: 703-648-6437 Data_Set_Credit: The stratigraphic data stored in the National Coal Resources Data System (NCRDS) was submitted from the middle 1970's through state cooperative programs. The data for the Pittsburgh coal bed was used with the permission and through the cooperation of coal geologists (primary contacts listed) at the West Virginia Geological and Economic Survey (Nick Fedorko), the Pennsylvania Bureau of Topographic and Geologic Survey (James R. Shaulis and Viktoras W. Skema), the Ohio Division of Geological Survey (Richard W. Carlton) and the Maryland Geological Survey (Dave Brezinski). [WVGES, PAGS, OHGS, and MDGS, respectively.] Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Deductive_Estimate: The range of elevation values in the point-source information was 13 to 2620 feet. The resultant range of the gridded surface was 13 to 2620 feet; extrapolation was used over the x,y extent plus 5%. The average absolute Z-error of the grid was 1.6 feet, which is 0.04 percent of the range. Logical_Consistency_Report: Topologically clean Completeness_Report: Input points were irregularly distributed over the spatial extent of the study, therefore areas of sparse data will not reflect ground truth. There is a point coverage available (c9024dpe) that contains most point elevations used to create this map. The main bench of the Pittsburgh coal was selected by name from the stratigraphic data base stored in StratiFact, a relational data base manager in use by the USGS National Coal Assessment. The original data submitted to NCRDS may not have had the Pittsburgh main bench identified (stratigraphically below the Pittsburgh roof coals), a task conducted in StratiFact by examination of cross sections of drill holes. A coverage of structure contours over the entire Pittsburgh horizon areal extent, sc024bsn, is also available. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: A wide variety of data sources were used as input to this data set. The worst horizontal error is expected to be approximately 1/4 mile. Original data were stored in NCRDS in latitude/longitude coordinates with a possible precision of decimal seconds. Some loss of precision was made upon conversion to StratiFact. Location coordinates were converted to Albers Equal Area projection (.01 meter precision) prior to gridding in ISM. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The raw gridding input data represent calculations: subtraction of the depth to the Pittsburgh Coal main bench from the surface (topographic) elevation of each borehole or point of measurement. The original measurement errors associated with the depth and surface elevation are unknown. In addition, for some locations only the elevation on the bottom of the Pittsburgh main bench (not the top) was available and was therefore used. The thickness of the Pittsburgh is less than the possible vertical accuracy of approximately 50 feet. Lineage: Process_Step: Process_Description: Pittsburgh Coal data from NCRDS printed and verified against original data sources. Process_Date: 1995 Process_Step: Process_Description: Corrections made to West Virginia and Maryland data in StratiFact. Corrections made to Pennsylvania data in NCRDS (Ingres). Pennsylvania data downloaded to StratiFact. StratiFact data base obtained for Ohio from OHGS. Process_Date: 1995-1996 Process_Step: Process_Description: Editing of individual data bases in StratiFact to eliminate data coding differences between states. Process_Date: 1996-1997 Process_Step: Process_Description: Obtained approximately 1000 elevations on the BOTTOM of the Pittsburgh coal bed from 11 WVGES Open-File maps of Wetzel County, WV (See open- file map for citations). Obtained approximately 650 elevations on the BOTTOM of the Pittsburgh coal bed from PAGS Westmoreland, Fayette, and Washington county reports. 85 elevations on the BOTTOM of the Pittsburgh coal bed from MDGS unpublished map. Added data to separate StratiFact data bases. Process_Date: 1997 Process_Step: Process_Description: Gridding of 7,101 elevations (ISM7.1), further addition and refinement of data values in StratiFact data bases. Final grid parameters used: normal minimum tension surface algorithm, 300 meter cell size, extrapolation over specified x,y extent plus 5%. Average Z-error was 1.6 feet. Grid was contoured with 50-foot interval and made into an ASCII output file. Decision was made to leave small contour polygons in the resulting file and not to subjectively remove them, even though they may not be real. Process_Date: 1997 Process_Step: Process_Description: Import contours to ARC/INFO for the entire basin, using conversion ARC/INFO AML provided by Illinois State Geological Survey. Rectangular area used as clip cover during import. Process_Date: 1997 Process_Step: Process_Description: Checked attributes of cover. Deleted 3 small polygons not having polygon labels. Process_Date: 1997 Process_Step: Process_Description: Clipped contours to the known resource areas defined in USGS Open-File Report 96-280 (ARC/INFO coverage c9024ro). Process_Date: 1997 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.00001 Longitude_Resolution: 0.00001 Geographic_Coordinate_Units: decimal degrees Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: c9024st.pat Entity_Type_Definition: polygon attribute table for coverage Entity_Type_Definition_Source: ARC/INFO Attribute: Attribute_Label: elevation_st Attribute_Definition: average elevation value of bounding contour lines Attribute_Definition_Source: ARC/INFO Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 25 Range_Domain_Maximum: 2625 Attribute_Value_Accuracy_Information: Attribute_Value_Accuracy: 50 Attribute_Value_Accuracy_Explanation: elevation on top of the Pittsburgh coal bed main bench (exclusive of roof coals) in feet was created by subtraction of depth down drill hole from surface elvation, gridded, and contoured to nearest 50 feet; accuracy plus or minus one contour interval. Entity_Type: Entity_Type_Label: c9024st.aat Entity_Type_Definition: arc attribute table for coverage Entity_Type_Definition_Source: ARC/INFO Attribute: Attribute_Label: elevation_st Attribute_Definition: elevation value of contour lines Attribute_Definition_Source: ARC/INFO Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -999* Range_Domain_Maximum: 2600 Attribute_Value_Accuracy_Information: Attribute_Value_Accuracy: 50 Attribute_Value_Accuracy_Explanation: elevation on top of the Pittsburgh coal bed main bench (exclusive of roof coals) in feet was created by subtraction of depth down drill hole from surface elvation, gridded and contoured to nearest 50 feet; accuracy plus or minus one contour interval. *NOTE: values of -999 are assigned to the outcrop, which was used as a clipping polygon and are not true elevation values. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Susan J. Tewalt Contact_Address: Address_Type: mailing address Address: MS 956 National Center City: Reston State_or_Province: Virginia Postal_Code: 20192 Country: USA Contact_Voice_Telephone: 703-648-6437 Resource_Description: Pittsburgh Coal dataset Distribution_Liability: This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ARCE Format_Version_Number: 7.1.1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: