ON-006-21M Alluvial Fan Mapping of Garfield County, Colorado (Map) 12/17/2025 ON-006-21M Alluvial Fan Mapping of Garfield County, Colorado (Map) The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-21D Alluvial Fan Mapping of Garfield County, Colorado (Data) - v20251120 12/17/2025 ON-006-21D Alluvial Fan Mapping of Garfield County, Colorado (Data) – v20251120 The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-20M Alluvial Fan Mapping of Chaffee County, Colorado (Map) 12/17/2025 ON-006-20M Alluvial Fan Mapping of Chaffee County, Colorado (Map) The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-20D Alluvial Fan Mapping of Chaffee County, Colorado (Data) - v20251201 12/17/2025 ON-006-20D Alluvial Fan Mapping of Chaffee County, Colorado (Data) – v20251201 The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-19M Alluvial Fan Mapping of Boulder County, Colorado (Map) 12/16/2025 ON-006-19M Alluvial Fan Mapping of Boulder County, Colorado (Map) The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-19D Alluvial Fan Mapping of Boulder County, Colorado (Data) - v20251120 12/16/2025 ON-006-19D Alluvial Fan Mapping of Boulder County, Colorado (Data) – v20251120 The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-18D Alluvial Fan Mapping of Pitkin County, Colorado (Map) 12/15/2025 ON-006-18M Alluvial Fan Mapping of Pitkin County, Colorado (Map) The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
ON-006-17M Alluvial Fan Mapping of Clear Creek County, Colorado (Map) 12/15/2025 ON-006-17M Alluvial Fan Mapping of Clear Creek County, Colorado (Map) The Colorado Geological Survey develops and provides a variety of geologic hazard maps for various state and local governments with land use and hazard mitigation planning in mind. To prepare for post-wildfire natural hazards, the CGS has mapped alluvial fans as well as high-angle fans and (or)… Read More
OF-23-02 Geologic Map of the Ignacio Quadrangle, La Plata County, Colorado 12/11/2025 OF-23-02 Geologic Map of the Ignacio Quadrangle, La Plata County, Colorado The purpose of this publication is to describe the geology, mineral and groundwater resources, and geologic hazards of the Ignacio 7.5-minute quadrangle. This map is part of the STATEMAP geologic mapping program in La Plata County near Durango, including the Bondad Hill, Loma Linda, and Gem Village quadrangles, which provide… Read More
OF-23-01 Geologic Map of the Badger Wash Quadrangle 12/11/2025 OF-23-01 Geologic Map of the Badger Wash Quadrangle, Mesa County, Colorado The purpose of this publication is to describe the geology, mineral and groundwater resources, and geologic hazards of the Badger Wash 7.5-minute quadrangle. This map is part of a STATEMAP geologic mapping program on Colorado’s Western Slope, near Grand Junction. Nearby completed CGS maps are the Mack, Fruita,… Read More
OF-22-07 Geologic Map of the Spinney Mountain Quadrangle 12/11/2025 OF-22-07 Geologic Map of the Spinney Mountain Quadrangle, Park County, Colorado The purpose of this publication is to describe the geology, geologic resources, and geologic hazards of the Spinney Mountain 7.5-minute quadrangle. This quadrangle is located within Colorado’s South Park basin, just south of Spinney Mountain State Park. Nearby completed CGS maps are the Hartsel, Antero Reservoir NE, and… Read More
The Flatirons, Chautauqua Park, Boulder, CO (December, 2026 CGS Geology Calendar). Photo credit: Orna Buch-Leviatan (CGS) 12/03/2025 2026 Colorado Geology Calendar Brought back for its fourth year running, our popular annual wall calendar showcases a varied and beautiful photo tour around the state. We’re excited to share this next collection of photographs from our talented CGS staff members (both current and former). Designed to keep you visually “in-the-know” on colorful Colorado… Read More