2022-03-15 | CGS Admin
— OF-20-11 Alkaline Complexes of the Wet Mountains Area, Colorado: A Geological Summary, Bibliography, and Data Compilation of Critical Mineral Laboratory Results With renewed interest in critical minerals driven by global demand and consequent shortages, the CGS funded a compilation of historical sample results and a literature review, along with a brief review of the geological context.
OF-20-09 Review of the Jefferson County Water Supply Policies and Analyses for Land Development in Mountain Areas — The perennial issue of development versus the protection of groundwater resources is the general subject of this report. Specifically, Jefferson County asked the CGS to review some of their land development and zoning regulations that relate to water supplies.
In addition, as we review our past work, we are bringing reports and presentations related to our mission that have not been formally published including:
WAT-2005-02 Natural Acid Rock Drainage in Colorado: Overview and Recent Investigations — A PowerPoint presentation on this critical ground- and surface-water issue.
CGS actively participates in the STATEMAP portion of the US Geological Survey’s National Cooperative Geologic Mapping Program (NCGMP), a nation-wide effort to generate comprehensive geologic maps of individual 7-1/2-minute topographic quads. Following one or sometimes two seasons of intensive field work by a team of researchers, field information is carefully compiled, reviewed, and released as one of our geologic quadrangle maps. These are in the form of high-resolution PDF files along with a corresponding package of GIS data.
Continuing our long-standing mapping efforts in northern Front Range areas, these two in Weld County are in areas experiencing continued growth and development:
— OF-19-02 Geologic Map of the Gowanda Quadrangle, Weld County, Colorado between Longmont (west) and Platteville (east), Frederick (north) and Johnstown (south), Colorado.
— OF-21-04 Geologic Map of the Hardin Quadrangle , Weld County, Colorado along the South Platte River, east-southeast of Greeley, Colorado.
The Geologic Mapping Advisory Committee (GMAC)—with representatives from State, Federal, and Tribal governments, academia, and the private sector—select which Colorado quadrangles are included in this ongoing program. Our
STATEMAP progression map shows the many quads that have been completed, are in progress, or under current consideration across the state. The program provides crucial information to many constituents on geologic hazards, mineral resources, and groundwater, as well as informing a range of land-use issues across the state.
Pierre Shale (gray) exposed along St. Vrain Creek in Weld County, Colorado. Photo credit: Stephen Keller for the CGS. Check dams along drainage ditch, Clear Creek County, Colorado. Photo credit: Colorado Geological Survey. Pyrite, a metallic sulfide mineral, found in the dump of the Allan Emory Mine in Summit County, Colorado. Photo credit: Colorado Geological Survey. An exposure of the Triassic Dolores Formation on the east side of the Lemon Reservoir dam on the Florida River in La Plata County, Colorado, May 2019. Beds are dipping south along the Hogback Monocline that separates the San Juan Basin to the south from the San Juan Dome to the north. Here the fluvial sediments consist of interbedded sandstone, siltstone, and mudstone with sandstone dominating. Although not recognized as a major aquifer the sandstone can carry groundwater and at this location water is seeping out through fractures. Photo credit: Peter Barkmann for the CGS. Close-up of outcrop from quartz-barite-thorite vein in the Wet Mountains, Colorado, June 2018. Photo credit: Mike O’Keeffe for the CGS.
Citations, Categories & Tags
Barkmann, Peter E., Kenneth Swift Bird, and Karen A. Berry. “OF-20-09 Review of the Jefferson County Water Supply Policies and Analyses for Land Development in Mountain Areas.” Water Resources. Open File Report. Golden, CO: Colorado Geological Survey, July 2021.
Keller, Stephen M., Kassandra O. Lindsey, and Matthew L. Morgan. “OF-19-02 Geologic Map of the Gowanda Quadrangle, Weld County, Colorado.” Geologic, 1:24,000. Open File Report. Golden, CO: Colorado Geological Survey, December 2021.
O’Keeffe, Michael K., Alexander I. Peretyatko, and Asha A. Mahatma. “OF-20-11 Alkaline Complexes of the Wet Mountains Area, Colorado: A Geological Summary, Bibliography, and Data Compilation of Critical Mineral Laboratory Results.” Geology and Mineral Resources. Golden, CO: Colorado Geological Survey, April 2021.
Palkovic, Martin J., and Matthew L. Morgan. “OF-21-04 Geologic Map of the Hardin Quadrangle, Weld County, Colorado.” Geologic, 1:24,000. Open File Report. Golden, CO: Colorado Geological Survey, December 2021.
Sares, Matthew A. “WAT-2005-02 Natural Acid Rock Drainage in Colorado: Overview and Recent Investigations.” Water Resources presented at the Colorado Geological Survey, Denver, CO, July 22, 2005.