Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Originator: Biewick, L.R.H. Originator: Mercier, T.J. Originator: Bureau of Land Management Originator: Taylor, D. Originator: Levitt, P. Originator: Deikman, D. Originator: Vlahos, B. Publication_Date: 1999 Title: nwcoown (Land and Federal mineral ownership coverage for northwestern Colorado) Geospatial_Data_Presentation_Form: map Publication_Information: Publication_Place: Denver, CO Publisher: U.S. Geological Survey Online_Linkage: Description: Abstract: This Arc/Info coverage contains land status and Federal mineral ownership for approximately 26,800 square miles in northwestern Colorado. The polygon coverage (which is also provided here as a shapefile) contains two attributes of ownership information for each polygon. One attribute indicates where the surface is State owned, privately owned, or, if Federally owned, which Federal agency manages the land surface. The other attribute indicates which minerals, if any, are owned by the Federal govenment. This coverage is based on land status and Federal mineral ownership data compiled by the U.S. Geological Survey (USGS) and three Colorado State Bureau of Land Management (BLM) former district offices at a scale of 1:24,000. This coverage was compiled primarily to serve the USGS National Oil and Gas Resource Assessment Project in the Uinta-Piceance Basin Province and the USGS National Coal Resource Assessment Project in the Colorado Plateau. Purpose: As United States energy resources continue to be examined for potential development, there is sustained interest in Federally owned energy resources in the western United States. The U.S. Geological Survey's GIS data sets of surface and Federal mineral ownership, joined with USGS geologic investigations, provides information on where Federally owned energy resources are located and how much Federal petroleum and coal exists. These ownership and resource data are the basis for answering complex geospatial queries when the data are combined with quality, structure and other parameters generated from geologic investigations. Combining information on land status, Federal mineral status, and geology helps policy makers and land-use planners make informed decisions regarding use of Federal land and energy resources to meet diverse social needs. Surface ownership can differ from energy and other mineral ownership for the same piece of land. For example, the oil and gas may be Federally owned, but the surface may be under the jurisdiction or management of State, Tribal, or private groups. This separation of jurisdiction may have legal ramifications in the development or non-development of energy resources. The U. S. Geological Survey (USGS), in cooperation with the Bureau of Land Management (BLM) and State agencies, is collecting ownership files and compiling them in Arc/Info coverages. The coverages contain a USGS standardized attributing scheme and are stored in a data library where they are accessed and combined with models of oil, gas and coal geology to assess National energy resources (see information from the U.S. Geological Survey available on 10/5/99 on the World Wide Web at and at ). Similar data are available for northeastern Utah (see ) primarily to serve the U.S. Geological Survey National Oil and Gas Resource Assessment Project in the Uinta-Piceance Basin (province 20) and in southern Wyoming (see ) for portions of provinces 36, 37 and 39. The Federally owned energy resources play an important role in supplying energy to our Nation. Of the 26 million acres of Federal Mineral Estate in Colorado, 20 million acres are open to oil and gas leasing (information from the Bureau of Land Management available on 9/10/99 on the World Wide Web at ). In 1998, 1.37 million acres of Public Lands in Colorado were in producing status with 2,387 producing oil and gas wells. Coal production from 28 leases on Public Lands in Colorado was over 22.8 million short tons in 1998. Federally owned energy resources also play an important part in the economy of our Nation. 1998 Federal mineral royalties, rents, and bonuses produced financial transfers to Colorado of over $43 million, and the Federal collections were over $90 million (information from the Bureau of Land Management available on 9/10/99 on the World Wide Web at ). Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19990910 Currentness_Reference: completion date Status: Progress: Complete Maintenance_and_Update_Frequency: Unknown Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -109.0596 East_Bounding_Coordinate: -106.1250 North_Bounding_Coordinate: 41.0035 South_Bounding_Coordinate: 37.7500 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Piceance Basin Theme_Keyword: Federal mineral ownership Theme_Keyword: Sand Wash Basin Theme_Keyword: land status Theme_Keyword: land ownership Theme_Keyword: land-use planning Theme_Keyword: Federal coal ownership Theme_Keyword: Federal oil and gas ownership Theme_Keyword: Federal surface management Theme_Keyword: Surface management Theme_Keyword: Public lands Place: Place_Keyword_Thesaurus: None Place_Keyword: Piceance Basin Place_Keyword: northwestern Colorado Place_Keyword: western United States Place_Keyword: Sand Wash Basin Place_Keyword: Colorado Plateau Place_Keyword: Province 20 Place_Keyword: Uinta-Piceance Basin Province Temporal: Temporal_Keyword_Thesaurus: None Temporal_Keyword: 1999 Access_Constraints: None Use_Constraints: The surface and mineral management status are published as general planning and management tools. The official land records in Bureau of Land Management (BLM) offices or other Federal and/or State agencies should be checked for status of specific tracts of land. Comparison with other data sets on surface and mineral ownership for the same area from other time periods may reveal inconsistencies resulting from changes in land and mineral ownership or in mapping conventions over time. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Data_Set_Credit: Others who contributed toward the completion of these data include: Buchanan, R., Fowler, B., Hackett, V., Senti, A., Wells, R., Wilkenson, J., and Witherby, K. Native_Data_Set_Environment: Arc/Info Version 7.2.1 on Windows NT operating system Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: This coverage was created by performing UNIONs, MAPJOINs and APPENDs in Arc/Info of multiple ownership coverages obtained from the BLM between 1996 and 1999. The USGS processed surface and Federal mineral ownership coverages from the Colorado State BLM office and three Colorado BLM former district offices for the following field office areas: Little Snake River (LSFO), White River (WRFO), Glenwood Springs (GSFO), Grand Junction (GJFO) and Montrose (MFO). The land and mineral ownership coverages were combined in Arc/Info using the UNION command and slivers where deleted as needed. Attributes were added and populated in accordance with the standard attributing scheme developed by the USGS for land status and minerals owned by the Federal Government (see information from the U.S. Geological Survey available on 10/5/99 on the World Wide Web at ). In places where there was overlap or ownership was unknown, we honored the published BLM hardcopy maps and/or obtained updated information from the BLM. Areas of overlap between the districts were ERASEd in Arc/Info prior to performing the APPEND command. The coverage was then DISSOLVEd to ensure unique polygons for the attributes that define surface and Federal mineral ownership. Approximate accuracy is 90%. Logical_Consistency_Report: topologically clean, 9/10/99, Arc/Info Completeness_Report: This coverage is based on land status and Federal mineral ownership data compiled by the USGS and three Colorado BLM former district offices at a scale of 1:24,000. Arcs were snapped to the GCDB (Geographic Coordinate Database) landlines where available. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19930000 Title: Surface Management Status Mineral Management Status Colorado Canyon of Lodore Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19930000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1993 Source_Contribution: Land and mineral ownership in the Canyon of Lodore 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19940000 Title: Surface Management Status Mineral Management Status Colorado Carbondale Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19940000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1994 Source_Contribution: Land and mineral ownership in the Carbondale 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19970000 Title: Surface Management Status Mineral Management Status Colorado Craig Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19970000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1997 Source_Contribution: Land and mineral ownership in the Craig 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19920000 Title: Surface Management Status Mineral Management Status Colorado Delta Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19920000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1992 Source_Contribution: Land and mineral ownership in the Delta 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19940000 Title: Surface Management Status Mineral Management Status Colorado Douglas Pass Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19940000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1994 Source_Contribution: Land and mineral ownership in the Douglas Pass 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19940000 Title: Surface Management Status Mineral Management Status Colorado Glenwood Springs Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19940000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1994 Source_Contribution: Land and mineral ownership in the Glenwood Springs 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19950000 Title: Surface Management Status Mineral Management Status Colorado Grand Junction Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19950000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1995 Source_Contribution: Land and mineral ownership in the Grand Junction 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19930000 Title: Surface Management Status Mineral Management Status Colorado Gunnison Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19930000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1993 Source_Contribution: Land and mineral ownership in the Gunnison 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19930000 Title: Surface Management Status Mineral Management Status Colorado Meeker Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19930000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1993 Source_Contribution: Land and mineral ownership in the Meeker 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19970000 Title: Surface Management Status Mineral Management Status Colorado Montrose Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19970000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1997 Source_Contribution: Land and mineral ownership in the Montrose 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19920000 Title: Surface Management Status Mineral Management Status Colorado Nucla Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19920000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1992 Source_Contribution: Land and mineral ownership in the Nucla 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19950000 Title: Surface Management Status Mineral Management Status Colorado Paonia Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19950000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1995 Source_Contribution: Land and mineral ownership in the Paonia 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19920000 Title: Surface Management Status Mineral Management Status Colorado Rangely Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19920000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1992 Source_Contribution: Land and mineral ownership in the Rangely 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19980000 Title: Surface Management Status Mineral Management Status Colorado Saguache Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19980000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1998 Source_Contribution: Land and mineral ownership in the Saguache 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19900000 Title: Surface Management Status Mineral Management Status Colorado Silverton Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19900000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1990 Source_Contribution: Land and mineral ownership in the Silverton 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19970000 Title: Surface Management Status Mineral Management Status Colorado Steamboat Springs Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19970000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1997 Source_Contribution: Land and mineral ownership in the Steamboat Springs 30- x 60-minute quadrangle, Colorado. Source_Information: Source_Citation: Citation_Information: Originator: Bureau of Land Management Publication_Date: 19970000 Title: Surface Management Status Mineral Management Status Colorado Walden Geospatial_Data_Presentation_Form: map Source_Scale_Denominator: 100,000 Type_of_Source_Media: paper map Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 19970000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: BLM, 1997 Source_Contribution: Land and mineral ownership in the Walden 30- x 60-minute quadrangle, Colorado. Process_Step: Process_Description: Land and Federal mineral ownership files from three Colorado State BLM former district offices (Craig, Grand Junction and Montrose) were initially processed by the USGS to create ownership coverages that were used for the USGS Geologic Assessment of Coal in the Colorado Plateau Project (see information from the U.S. Geological Survey available on 10/5/99 on the World Wide Web at ). The coal assessment areas in northwestern Colorado include the Danforth Hills and Yampa coal fields, the Deserado coal area and the southern Piceance Basin (see information from the U.S. Geological Survey available on 10/5/99 on the World Wide Web at ). Digital files obtained from the BLM offices were in Arc/Info EXPORT format. 1:24,000-scale coverages of surface and mineral ownership were used from the Craig, Grand Junction and Montrose BLM former district offices for the following field office areas: White River, Glenwood Springs, Grand Junction, Little Snake River, Gunnison and Uncompahgre. The files were imported and combined using the UNION command and either the MAPJOIN or the APPEND commands to create ownership coverages for each of the coal assessment areas listed above (see information from the U.S. Geological Survey available on 10/5/99 on the World Wide Web at ). The union of coverages of dissimilar landlines produced an inordinate amount of sliver polygons. This problem was resolved by several different methods. The processing to remove slivers from the integrated land and Federal mineral ownership coverages was done using an Arc Macro Language (AML) program (deleteslivers.aml), the Arc/Info ELIMINATE command, and Arcedit. In places where digital files from the various BLM field offices overlapped, we honored the most current data or matched the published BLM hardcopy maps. Areas of overlap were ERASEd in Arc/Info prior to performing the APPEND command to combine adjacent files. The coverages were then clipped to the coal assessment study area boundaries and items (fields) were added for storage of ownership data according to the USGS surface and mineral management status attributing scheme, as follows -- Arc: additem SURF 8 8 c Arc: additem FEDMINS 8 8 c The item SURF defines surface management status in each polygon. The item, FEDMINS, holds Federal mineral ownership information. The items (fields) SURF and FEDMINS were populated based on the surface and mineral ownership attributes provided in the BLM coverages. The coverages were then DISSOLVEd with the #all and poly options to remove extraneous lines and to ensure unique polygons for the attributes SURF and FEDMINS. Process_Date: 19990000 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Process_Step: Process_Description: In 1999, the USGS processed ownership beyond the coal assessment areas to create one seamless coverage for northwestern Colorado. The coverage, 'nwcoown', includes the areas where Oil and Gas Plays will be assessed for the USGS Uinta-Piceance Basin Oil and Gas Assessment. In August, 1999, new files were received from the BLM by the USGS for Federal mineral ownership in the Grand Junction and former Glenwood Springs District Office areas and for surface ownership in the Glenwood Springs, Gunnison, Uncompahgre, and Little Snake River Field Office areas. These BLM files were used to update and expand the areal extent of the USGS ownership coverage in northwestern Colorado ('nwcoown'). Processing of the BLM files included: 1. Importing and projecting BLM coverages to geographic decimal degrees. 2. Extension or clipping of data to Colorado statelines to the north and west to match adjacent coverages in northeastern Utah (in press) and southern Wyoming (in press). 3. Referencing the new data to update the northwest Colorado ownership coverage ('nwcoown'). The surface ownership information in 'nwcoown' was modified to match the more recent data acquired from the BLM former Craig District Office for the Little Snake River Field Office area ('lsra_surf') and from the BLM former Montrose District Office for the Gunnison and Uncompahgre Field Office area ('mont_surf'). The mineral ownership information in 'nwcoown' was modified to match the current data acquired from the BLM former Grand Junction District Office for the Grand Junction Field Office area ('gjra_subs'). The mineral ownership file for the Gunnison and Uncompahgre Field Office areas ('mont_subs') is based on work done by the BLM in the late 1980s. Because the data is somewhat outdated, not quality controlled by the BLM and much of the area was not attributed to show Federal mineral ownership, the USGS attributed FEDMINS based on the published BLM hardcopy maps. These data were then INTERSECTed with the Montrose surface ownership coverage and APPENDed to 'nwcoown' after it was extensively edited to remove slivers, dangles and intersections. 4. Processing the new files to replace data in the northwest Colorado ownership coverage. This included adding and populating the items SURF and FEDMINS based on items in fields STATUS and MNO in the Glenwood Springs Field Office area ownership file ('grsa_own'). The Arc/Info FREQUENCY command was used as a means of checking the data before removing items and using the DISSOLVE command. 'gsra_own' was edited to remove slivers and all extraneous pseudonodes were eliminated before incorporating this data into 'nwcoown' using the UPDATE command. Commands used to process 'nwcoown' as needed included CLEAN, BUILD, LABELERRORS, DROPITEM, DISSOLVE, UNSPLIT NONE, UPDATE. The polygon attribute table ('nwcoown.pat') was corrected using ArcView table editting tools. To facilitate this process of locating and correcting line and polygon discrepancies between 'nwcoown' and new data from the BLM, arcs and labels in a copy of 'nwcoown' were editted in Arcedit while viewing 'nwcoown' in comparison to the original BLM files in ArcView. This data set has gone through extensive processing to eliminate slivers. Polygon topology exists and there are no label errors. Although the intent is to publish a coverage free of errors, it is possible that nondetection of some slivers may have occurred. Such detection of additional slivers would only be possible in working with portions of this data at a larger scale than 1:24,000-scale. Another dissolve following manual elimination of slivers resulted in 'nwcoown' containing 8650 polygons (18951 arcs). The coverage was carefully checked against the original BLM coverages in ArcView and edited as necessary in ArcView and Arcedit. Extraneous pseudonodes have been deleted. Process_Date: 19990000 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Process_Step: Process_Description: For those interested in coverage processing details: Past tests using the Arc/Info CLEAN command to collapse sliver polygons proved to be unsuccessful. In the process of collapsing slivers, the CLEAN command creates numerous (hundreds of) new polygons that contain no label points and therefore have lost the attribute information (i.e., corners of polygons become collapsed). Because of the magnitude of work involved in adding the attribute information back into the coverage, it is suggested that the tedious process of manual editing of slivers is of equal or less magnitude and possibly introduces less error. The manual editing process was performed systematically by 100,000-scale quadrangle until all node errors and obvious polygon errors were corrected. The time involved in this manual editing process ranged from 30 minutes to several hours per 100,000-scale quadrangle. The coverage was rebuilt for topology several times as necessary. One procedure used is as follows -- In Arcedit, drawsel all polygons with areas lt .00001 decimal degrees. Create a window as big as one 100,000-scale quadrangle. It works well on a 21-inch screen to divide the 100,000-scale quadrangle into twelfths to zoom in and check the data. Create further zoomed-in windows as needed for more detail of suspect slivers. In this process, other slivers that may not be highlighted (selected polygons), are also found. Proceed through the entire 30- by 60-minute quadrangle by panning across and down, minimizing windows of slivered areas. When finished analyzing the selected polygons in the entire 30- by 60-minute quadrangle, change edit feature to arc (now selected polygons disappear). Maximize the windows that contain slivers one by one to edit arcs and labels. Also selected were arcs that are sliver extensions of polygons. Sometimes these arcs, when selected, are found to overlap other arcs. The draw environment needs to be arc, label, node errors and sometimes arc intersects. Set arcsnap on. Labels help identify minute slivers that would not otherwise be detected. The arcs that make up these slivers can be selected with edit feature arc, by selecting directly on the label, deleting the arcs and subsequently deleting the labels. Use the command intersectarcs all. Continue this process of selecting arcs, splitting where needed, reselecting, deleting, and moving nodes to close polygons where dangles are created in the process. Always display arcs and labels; they go hand in hand in defining polygons (even sliver polygons). Both arcs and labels need to be deleted to avoid numerous labelerrors that can result in incorrect attributes associated with polygons. After zooming into detected slivered areas and fixing them, gradually zoom out to facilitate identification and deletion of additional sliver problems. Process_Date: 19990000 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Process_Step: Process_Description: For those interested in processing steps done by the BLM before the USGS acquired the data files: FORMER CRAIG DISTRICT OFFICE (LITTLE SNAKE RIVER AND WHITE RIVER FIELD OFFICE AREAS) -- The BLM land and mineral ownership data were originally digitized from 1:24,000-scale surface and subsurface ownership maps by contractor in the 1980's in Lambert projection. The overlays that were digitized were created by realty specialists of land ownership. The data were converted to Automated Mapping System (AMS) in the early 1990's. When BLM switched to the Automated Digitizing System (ADS) the data were projected to UTM Zone 13 and snapped to a digitized Public Land Survey System (PLSS). In the mid 1990's, the data were verified and converted to the Map Overlay Statistical System (MOSS). The individual 7.5' quadrangle files were merged in MOSS and converted to MOSS export format. The data were transferred from a PRIME server in Denver to a local PC in Craig and imported into AutoCAD through the MOSS2DXF translator. In AutoCAD, individual line segments were joined to make continuous lines, interior lines separating mineral status were removed and the data were snapped to the AutoCAD Geographic Coordinate Data Base (GCDB) layer. In 1996-1997, the BLM converted to the UNIX based Arc/Info GIS system. The AutoCAD files were exported to DXF format and brought into Arc/Info utilizing the DXFARC command. A separate mineral status layer was created. Individual 7.5' quadrangle files were processed in Arcedit and merged into 30' x 60' quadrangle blocks. The 30' x 60' quadrangle files were cleaned and merged to create field office area wide coverages. Some of the data were converted from MOSS export files to Arc/Info coverages using the MOSSARC command. FORMER GRAND JUNCTION DISTRICT OFFICE (GLENWOOD SPRINGS AND GRAND JUNCTION FIELD OFFICE AREAS) -- Land status data were manually compiled onto 7.5' quadrangle maps from Master Title Plats by the field office area specialist and digitized in 1989 and 1994 in the Grand Junction and the Glenwood Springs Field Office areas respectively. Mineral ownership data were manually compiled onto 7.5' quadrangle maps from BLM 100K surface and mineral mangement status maps by the BLM staff. The data were originally processed using the AMS and ADS software. Later the data were converted to MOSS. When the BLM converted to the UNIX base Arc/Info GIS system, the data were translated to Arc/Info and updated using Arcedit. In 1997, ownership data were updated and arcs were snapped to landlines in the Geographic Coordinate Database (GCDB) where available. The GCDB was derived from various sources and represents the best available source of the geographic location of corners in the Public Land Survey System, in a digital format. The accuracy of the data is based on the accuracy of the GCDB corners that provide the control. The accuracy will vary depending on the source of the GCDB data. Estimated reliabilities of the geographic location of corners are documented in the GCDB LX file for each township. This data will be available through the BLM as an associated point coverage in the future. Further information on the GCDB can be downloaded from the Colorado BLM web site at . In some cases, the data for each 7.5' quadrangle were screen verified or plotted at a scale of 1:24,000 and verified for positional accuracy and attributed by the field office area realty specialist, however, errors may exist. In other cases the data have been inspected by the GIS staff, but have not been verified for accuracy of the position of spatial objects by the data steward. FORMER MONTROSE DISTRICT OFFICE (GUNNISON AND UNCOMPAHGRE FIELD OFFICE AREAS) -- In 1986 and 1987 the BLM transferred land and mineral ownership data from Master Title Plats to USGS 7.5' quadrangle maps off which they digitized. The data were provided to the USGS in 1996 as separate surface and mineral management status MOSS export files. All the data were provided by 7.5' quadrangle, except the mineral ownership in the Uncompahgre Field Office area were provided in one merged file. The USGS imported the files into Arc/Info using the MOSSARC command, APPENDed all the individual quadrangles and further processed the data as stated previously in this document. Process_Date: 19990000 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 8649 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: nwcoown.pat Entity_Type_Definition: Polygon Attribute Table Entity_Type_Definition_Source: None Attribute: Attribute_Label: Area Attribute_Definition: Area of polygon Attribute_Definition_Source: Software computed Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.00000 Range_Domain_Maximum: 1.32218 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: Perimeter Attribute_Definition: Perimeter of polygon Attribute_Definition_Source: Software computed Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.00070 Range_Domain_Maximum: 75.37735 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: Nwcoown# Attribute_Definition: Internal feature number Attribute_Definition_Source: Software computed Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2 Range_Domain_Maximum: 8650 Attribute: Attribute_Label: Nwcoown-id Attribute_Definition: Feature identification number Attribute_Definition_Source: User Defined Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 8649 Attribute: Attribute_Label: Surf Attribute_Definition: land ownership, surface management status BLM ---- Bureau of Land Management BREC ---- Bureau of Reclamation DOE ---- Department of Energy FS ---- Forest Service NM ---- National Monument NPS ---- National Park Service PRIVATE ---- Private SDOW ---- State, County or City Dept. of Wildlife SP ---- State, County or City Park SREC ---- State, County or City Recreation Area STATE ---- State WR ---- Wildlife Refuge Attribute_Definition_Source: User Defined Attribute_Domain_Values: Unrepresentable_Domain: Character field Attribute: Attribute_Label: Fedmins Attribute_Definition: Federal mineral ownership, subsurface Ownership ALL ---- Federal government maintains mineral rights for all of the minerals. 3/4 ALL ---- Federal government maintains mineral rights for 3/4 of all of the minerals. COAL ---- Federal government maintains mineral rights for coal only. NONE ---- Federal government maintains mineral rights for none of the minerals. OG ---- Federal government maintains mineral rights for oil and gas only. OGC ---- Federal government maintains mineral rights for oil, gas and coal only. OTHER ---- Federal government maintains mineral rights for other minerals. WATER ---- body of water. Attribute_Definition_Source: User Defined Attribute_Domain_Values: Unrepresentable_Domain: Character field Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Resource_Description: Arc/Info export file and shapefile Distribution_Liability: This data is not a legal document and is not intended to be used as such. Any use of trade, product, or company names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. 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 by the USGS regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. Metadata_Reference_Information: Metadata_Date: 19990722 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Laura R.H. Biewick Contact_Organization: U.S. Geological Survey Contact_Position: geologist Contact_Address: Address_Type: mailing and physical address Address: P.O. Box 25046, MS 939 City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-7773 Contact_Facsimile_Telephone: (303) 236-0459 Contact_Electronic_Mail_Address: lbiewick@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 ------------------------------------------------------------------------ Generated by mp version 2.4.8 on Tue Sep 14 15:51:54 1999