OF-03-02 Geologic Hazards of the Georgetown, Idaho Springs, and Squaw Pass Quadrangles, Clear Creek County, Colorado


This report provides geologic hazard information to guide initial land-use planning to government planners, resource and real estate developers, consultants, and interested citizens. The file includes map plates, shape files, and topographic maps. A hazards report detailing geologic setting, geologic hazards, geologic constraints, acknowledgements, and references is also included. 22 pages. 2 plates. 1 figure. Digital ZIP download. OF-03-02D

The report was prepared to assist Clear Creek County in planning and land-use management decisions. The map plates show geologic conditions on a regional scale on the basis of 1:24,000-scale mapping. Charts on each of the two map plates show applicability of the potential hazards to a variety of common land uses. It is recommended for initial land-use planning only. It is not intended for use in project or site-specific planning.

Plates 1 and 2 describe and depict geologic hazards such as landslides, rockfalls, debris flows, and unstable slopes in the project area. Potential snow-avalanche and debris-flow paths, shallow groundwater and potential flood areas, major fault zones, and mine waste sites are also addressed herein. Some of the shapefiles include geologic hazards by type, geology, topography, slope inclination, stream channels, and a series of shaded relief maps.

The occurrence and severity of geologic hazards is commonly associated with, but not entirely dependent upon, increased slope inclination and aspect. The topography in Clear Creek County area becomes much more extreme from east to west, and the abundance of geologic hazards similarly increases from the Squaw Pass quadrangle to the Georgetown quadrangle. The three most significant geologic hazards in the project area are rockfall areas, landslides, and debris flows.