THE CENTRAL COLORADO ASSESSMENT- MULTI-DISCIPLINARY GEOSCIENCE IN SUPPORT OF RESOURCE MANAGEMENT OF PUBLIC LANDS

This study provides comprehensive geoscience data and interpretations that will allow federal, state, and local land management entities to make informed land-use decisions in central Colorado. Included in the study are resource assessments of metallic and industrial mineral resources and aggregate. The study addresses the geochemical and environmental effects of historic mining activity on surface and ground water and riparian biology, the geo-environmental effects of wildfires, the geologic controls on groundwater quantity and quality, and provides rock property information that will aid in assessing the potential for geologic hazards, such as landslides and stream flooding. Addressing these issues requires comprehensive regional digital products and datasets presented in a GIS framework such as: 1) geologic maps, 2) surface water, stream sediment and bedrock geochemistry, geochronology and isotopic databases, 3) topical and regional studies of water, and mineral resources, 4) regional geophysical datasets, 5) remote sensing data, and 6) upgrades to mineral deposit site information. The study area is comprised of about 50% public land, extending from the Wyoming to the New Mexico borders and from the eastern edge of the Colorado Front Range, westward to approximately the crest of the Saguache Range. The area includes much of the Colorado Mineral Belt, a northeast trending zone that has produced most of the state's base and precious metals. Eight new adjoining 1:100,000 scale geologic maps will be completed in the central and northern part of the area. In the remainder of the area, published geologic maps at various scales are being integrated to provide a nominal 1:100,000 scale map. The new and compiled maps are being combined to provide a seamless regional geologic map that will be attributed with age, rock composition and geochemistry, physical properties, geologic names, and mineral deposit information. Regional geophysical datasets will allow recognition of basement lithology and structures, buried Tertiary and Cretaceous plutons and areas of hydrothermal alteration. Remote sensing data (TM, AVIRIS, and ASTER) will define areas of hydrothermal alteration and mine wastes. Stream sediment, water, and bedrock geochemistry data will aid in the evaluation of mineral resources, biology and water quality studies.