Janet Carter 2000 Version 1.0, March 21, 2000 map USGS Open-File Report USGS OFR00-471 Reston, VA U.S. Geological Survey http://water.usgs.gov/lookup/getspatial?ofr00471_mnktscon Janet Carter 1999 Hydrologic Investigations Atlas HA-744-B Rapid City, SD U.S. Geological Survey This data set represents geologic structure contours for the top of the Minnekahta Limestone, Black Hills, South Dakota. This data set was created as part of the Black Hills Hydrology Study (BHHS). The BHHS is a long-term investigation that was initiated in 1990 as a cooperative effort between the U.S. Geological Survey (USGS), the South Dakota Department of Environment and Natural Resources (DENR), and the West Dakota Water Development District. West Dakota represents various local and county cooperators. The purpose of the study is to assess the quantity, quality, and distribution of surface and ground water in the Black Hills area of western South Dakota (Driscoll, 1992). The study area includes parts of Butte, Custer, Fall River, Lawrence, Meade, and Pennington counties in South Dakota. Reviews_Applied_to_Data: This electronic report was subjected to the same review standard that applies to all U.S. Geological Survey reports. Reviewers were asked to check the topological consistency, tolerances, attribute frequencies and statistics, projection, and geographic extent. The reviewers checked the metadata and a_readme.1st files for completeness and accuracy. Related_Spatial_and_Tabular_Data_Sets: Geologic structure contours for the Deadwood, Madison, Minnelusa, and Inyan Kara geologic units (ddwdscon, mdsnscon, mnlsscon, inkrscon) and data set of wells with geologic information (mnktswpt) for the Minnekahta Limestone. Digital data set of where the Minnekahta Limestone is absent as well as covered by alluvial deposits (mnktsurf). Also, surficial hydrogeology in the Black Hills study area (hydrogeo). Other_References_Cited: >Driscoll, D.G., 1992, Plan of study for the Black Hills Hydrology > Study, South Dakota: U.S. Geological Survey Open-File Report 92-84, > 10 p. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ARC/INFO format, this metadata file may include some ARC/INFO-specific terminology. 19990714 The contours were drawn with information on elevation, geologic outcrops and wells drilled as of 1998. Complete None Planned -104.07971957 -102.9560621 44.78460855 43.11753771 none geology structure contour Minnekahta Limestone inlandWaters none Black Hills South Dakota none These data should not be used at scales larger than 1:100,000 scale. Janet Carter U.S. Geological Survey Hydrologist mailing address

1608 Mt. View Rd.

Rapid City South Dakota 57702 USA 1-888-275-8747 (605) 355-4523 (jmcarter@usgs.gov) Compilation of this data set and the associated metadata was funded in cooperation with the South Dakota Department of Environment and Natural Resources and the West Dakota Water Development District. SunOS, 5.6, sun4u UNIX ARC/INFO version 8.0.1 U.S. Geological Survey 2000 map USGS open-file report OFR00-471 Rapid City, South Dakota U.S. Geological Survey http://water.usgs.gov/lookup/getspatial?ofr00471_mnktswpt Multiple visual checks were done to verify that the attribute data was coincident with the original source map. Chain-node topology present. This data set consists of geologic structure contours for the Minnekahta Limestone in the vicinity of the Black Hills, South Dakota. Paper plots at 1:100,000 scale were overlaid on the original mylar sheet and contour lines were compared. Positional accuracy of contour lines is dependent on the accuracy of the well locations in the USGS Ground Water Site Inventory data base. Janet Carter, U.S. Geological Survey Unpublished material map none none Rapid City, South Dakota U.S. Geological Survey 100000 mylar map 1999 Ground condition based on well-data as of July 1998. none The structure contours were digitized from the hand-drawn contours on this mylar base map. Jack A. Redden, U.S. Geological survey 1994 map open-file report OFR 95-81 Reston, Virginia U.S. Geological Survey 100000 mylar 1994 none none Some of the structural contours were modified from this product. Geologic outcrop areas, absent areas, and overlying alluvial deposits for the Minnekahta limestone were plotted on a mylar sheet at 1:100,000 scale. Outcrop areas for the Minnekahta Limestone were reselected from the data set of surficial hydrogeology ("hydrogeo"). Absent areas and overlying surficial deposits were taken from the data set ("mnktsurf"). For areas outside of the outcrop, information from wells was used to interpret the altitude of the top of the Minnekahta Limestone and draw contours. Contours were not drawn in areas where the Minnekahta Limestone outcrops, is absent, or is directly overlain by alluvial deposits. Well information is contained in the data set "mnktswpt". The mylar-based contours then were digitized. Line topology was created using the Arc/Info BUILD command. Pseudo nodes were removed using the UNSPLIT NONE command in Arcedit. Some arcs became jagged after the UNSPLIT. These arcs were smoothed interactively in Arcedit. The coverage then was rebuilt. Attribute items were added to the coverage arc attribute table. The attribute item INTERP was used to indicate where lines were to be dashed on the map of geologic structure contours. Dashed lines, represented by an INTERP value of 'Y', indicate that geologic structure was "interpreted" in the area, and was not known through geologic well logs. Other line segments, where there was confidence in geologic structure, were assigned a value of 'N' for the INTERP attribute item, indicating that structure for these contours was not interpreted. These non-interpreted lines were drawn as solid lines on the map. An automated method was used to assign values to the attribute item INTERP. Wells with information from geologic logs were used to interpret geologic structure. Wells with information for the Minnekahta Limestone were buffered at 1000 meters, creating polygons of singular and in some cases overlapping, well buffers. Countour lines within the the well buffers were assigned a value of 'N' to INTERP, as was done for the geologic outcrops. Contour lines assigned values to INTERP using geologic outcrops were not changed. Arc: BUFFER MNKT_WELLS MNKT_BUF1K # # 1000 # POINT Arc: IDENTITY MNKT_COUT MNKT_BUF1K MNKT_COUTB LINE # JOIN In Tables: Enter command: SEL MNKT_COUTB.AAT Enter command: RES INTERP CN 'Y' AND MNKT_BUF1K# NE 1 Enter command: MOVE 'N' TO INTERP Enter command: Q STOP In some instances where contour lines were close around a well, the above method assigned values of 'N' to INTERP where they should be 'Y'. Arcedit was used to change values of INTERP for these lines back to 'Y', so that they would appear dashed on the map (geologic structure interpreted). Attribute items that were joined to the arc attribute table and were associated with the IDENTITY outcrop and well buffer coverages were dropped. 19980714 First draft of metadata created by gjarrell using FGDCMETA.AML ver. 1.33 07/15/99 on ARC/INFO data set /home/student/gja/meta/mnktscon 20000321 Vector String 977 Universal Transverse Mercator 13 0.9996 -105.00 0.0000 500,000 0.0000 coordinate pair 0.9900000095367 0.9900000095367 Meters North American Datum of 1927 Clarke 1866 6378206.4 294.98 > >MNKTSCON.AAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 FNODE# 4 5 B - > 5 TNODE# 4 5 B - > 9 LPOLY# 4 5 B - > 13 RPOLY# 4 5 B - > 17 LENGTH 4 12 F 3 > 21 MNKTSCON# 4 5 B - > 25 MNKTSCON-ID 4 5 B - > 29 ALTITUDE 8 8 I - > 37 CI500 8 8 I - > 45 INTERP 1 1 C - > > FNODE# - Internal number of from-node TNODE# - Internal number of to-node LPOLY# - Internal number of the left polygon; set to 0 for this data set because there are no polygons RPOLY# - Internal number of the right polygon; set to 0 for this data set because there are no polygons LENGTH - Length of arc in meters MNKTSCON# - Internal sequence number (i.e. the record number) of the arc in the ARC file MNKTSCON-ID- User-assigned feature ID ALTITUDE - Altitude of top of geologic formation (in feet). Negative values indicate below sea level. CI500 - Item used for drawing 500-ft contour lines. A value of 9999 indicates that the contour is not a multiple of 500. INTERP - Item used for drawing solid and dashed contour lines. A value of 'Y' indicates that some interpretation was involved in drawing the contour line. A value of 'N' indicates that the contour line was drawn using geologic-outcrop or well-log information. none U.S. Geological Survey Ask USGS - Water Webserver Team mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) http://answers.usgs.gov/cgi-bin/gsanswers?pemail=h2oteam&subject=GIS+Dataset+ofr00471_mnktscon Although this data set has been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Other Overview description 00471 Export Full coverage 1 http://water.usgs.gov/GIS/dsdl/ofr00471_mnktscon.e00 Export Full coverage 1 http://water.usgs.gov/GIS/dsdl/ofr00471_mnktscon.e00.zip SDTS Full coverage zipped 1 http://water.usgs.gov/GIS/dsdl/ofr00471_mnktscon.tgz Other Full coverage zipped 1 http://water.usgs.gov/GIS/dsdl/ofr00-471_mnktscon_shp.tgz None. This dataset is provided by USGS as a public service. 20041108 U.S. Geological Survey Ask USGS -- Water Webserver Team mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) http://answers.usgs.gov/cgi-bin/gsanswers?pemail=h2oteam&subject=GIS+Dataset+ofr00471_mnktscon FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998