Entry_ID: (required) Entry_Title: Gamma-ray, Magnetic, and Topographic Data for the Colorado Front Range Group: Data_Set_Citation Originator(s): Duval, Joseph S.; Reed, John C.; Zietz, Isadore Title: Gamma-ray, Magnetic, and Topographic Data for the Colorado Front Range Publication: USGS Open-File Report Publication_Date: 2000 Publication_Place: Reston, Virginia Publisher: U.S. Geological Survey Data_Presentation_Form: raster digital data End_Group Keyword: Geophysical Data Group: Temporal_Coverage Start_date: 1978 Stop_date: 1979 End_Group Data_Set_Progress: In Work Group: Spatial_Coverage Southernmost_Latitude: 32 Northernmost_Latitude: 36 Westernmost_Longitude: -106 Easternmost_Longitude: -105 End_Group Location: Colorado Group: Data_Resolution Latitude_Resolution: 0.635 Longitude_Resolution: 0.635 End_Group Access_Constraints: None Use_Constraints: None Originating_Center: (required) Group: Data_Center Data_Center_Name: USGS ESIC-Open-File Report Sales Dataset_ID: USGS Open-File Report 2000-331 Group: Data_Center_Contact Last_name: USGS ESIC-Open-File Report Sales First_name: N/A Phone: (303) 202-4210 Group: Address Mail Stop 517 U.S. Geological Survey Box 25286, Building 810 Denver Federal Center Denver, CO 80225-0286 USA End_Group End_Group End_Group Group: Distribution Distribution_Media: online Distribution_Format : GXF Distribution_Size: 850 kilobytes Fees: none End_Group Group: Distribution Distribution_Media: online Distribution_Format : GXF Distribution_Size: 850 kilobytes Fees: none End_Group Group: Distribution Distribution_Media: online Distribution_Format : GXF Distribution_Size: 850 kilobytes Fees: none End_Group Group: Distribution Distribution_Media: online Distribution_Format : GXF Distribution_Size: 850 kilobytes Fees: none End_Group Group: Distribution Distribution_Media: online Distribution_Format : GXF Distribution_Size: 850 kilobytes Fees: none End_Group Group: Reference End_Group Group: Summary These data were originally obtained to aid in the estimate of uranium resources in the United States. The grid files presented here are in ASCII format that uses the definitions of the grid exchange format (GXF). The files can be viewed using a suitable word processing program. The different grids are: >Kfrco.gxf potassium concentrations in the rocks and soils >Ufrco.gxf uranium concentrations in the rocks and soils >Thfrco.gxf thorium concentrations in the rocks and soils >Magfrco.gxf residual magnetic field >Terrfrco.gxf digital elevations The data used to create the potassium (K), uranium (U), thorium (Th), and magnetic (Mag) grids were obtained as part of the National Uranium Resource Evaluation (NURE) Program of the U.S. Department of Energy (USDOE). The NURE Program included aerial surveys that collected gamma-ray and magnetic data. The aerial surveys were flown at a nominal altitude of 122 meters above the ground. The aerial survey flightlines were generally flown east- west with north-south tielines. For the data covering the mountains of the Colorado Front Range, the flightline spacing is 1 mile (1600 meters) for the east-west lines and about 8 miles (12.8 km) for the north-south tielines. For the data covering the plains to the east of the mountains, the flightline spacing is 3 miles (4800 m) for the east-west lines and about 16 miles (25.6 km) for the north-south tielines. In the mountains, helicopters were used with a detector volume of 2000 cubic inches (32.8 liters) of thallium doped sodium iodide (NaI(Tl)). Over the plains, fixed-wing aircraft were used with about 3300 cubic inches (54 liters) of NaI(Tl) detector. The magnetometers used were proton-precession magnetometers with base stations used to make diurnal corrections. The USDOE contracted with private contractors to conduct the aerial surveys and the contractors were responsible for all aspects of calibration and data processing. The data used to create the grid of digital elevations were derived from the U.S. Geological Survey (USGS) 1:250,000 topographic quadrangle maps. The topographic maps were digitized at intervals of three arc-seconds and were then averaged to intervals of 15 seconds. The resulting 15-second data were used to calculate the grid presented here. The units of the grid data are: >Potassium percent K >Uranium parts per million (ppm) eU >Thorium ppm eTh >Magnetic nano Teslas >Elevation meters End_Group Group: Related_URL URL_Type: URL: None Group: Description Originator: Geometrics, Inc. Publication_Date: 1979 Title: Aerial gamma ray and magnetic survey; Rock Springs, Rawlins, and Cheyenne quadrangles, Wyoming and the Greeley Quadrangle, Colorado Geospatial_Data_Presentation_Form: document Series_Information: Series_Name: Open-File Report Issue_Identification: GJBX-17-79 Publication_Information: Publication_Place: Grand Junction, CO Publisher: U.S. Department of Energy Other_Citation_Details: 5 volumes Online_Linkage: None End_Group End_Group Group: Related_URL URL_Type: URL: None Group: Description Originator: Geometrics, Inc. Publication_Date: 1979 Title: Aerial gamma ray and magnetic survey; Rockies/Laramie Range Project; Denver and Pueblo quadrangles, Colorado Geospatial_Data_Presentation_Form: document Series_Information: Series_Name: Open-File Report Issue_Identification: GJBX-49-79 Publication_Information: Publication_Place: Grand Junction, CO Publisher: U.S. Department of Energy Other_Citation_Details: 4 volumes Online_Linkage: None End_Group End_Group Group: DIF_Author Last_name: Schweitzer First_name: Peter Middle_name: N. Email: pschweitzer@usgs.gov Phone: (703) 648-6533 Group: Address 12201 Sunrise Valley Drive Mail Stop 954 Reston, VA 20192 USA End_Group End_Group DIF_Revision_Date: 20071119 Science_Review_Date: