From 1995 sites in the San Juan Mountains area, 1706 water and 1982 sediment samples were collected during June-July 1976 and analyzed for uranium. The area includes the southern third of the Colorado mineral belt which has yielded rich ores of gold, silver, copper, lead, zinc, and molybdenum. The broadly domed mountains are capped by 2500 m of Tertiary volcanics, deeply eroded to expose a Precambrian crystalline core. Adjacent plateaus underlain by Mesozoic sedimentary rocks were included in the reconnaissance. Average value of uranium in water samples from mountains was less than 0.5 parts per billion, from plateaus was 1-2 parts per billion, from Mancos shale areas exceeded 2 parts per billion. Anomalous sediment samples, 40 ppm uranium, came from near Storm King Mountain and upper Vallecito Creek. Other anomalous areas, including the Lake City mining district, were well defined by 4-30 parts per million uranium in sediment and 3-30 parts per billion uranium in water. Anomalous areas not previously reported indicate favorable areas for future exploration.

The following report describes the study of sediment in South Park, Colorado, the study taking 464 water samples to test for uranium in the Rocky Mountains.

A report discussing data collected during a detailed geochemiccal survey for uranium in streams draining parts of the Browns Park and North Park formations, in Craig, Colorado

Multivariate statistical analysis to support the National Uranium Resource Evaluation and to evaluate strategic and other commercially important mineral resources

This report provides uranium and other elemental data resulting from the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Cortez quadrangle, Colorado/Utah.

Report documenting the results of chemical analysis for 422 water and 1552 sediment samples in the Vernal quadrangle, Utah/Colorado. It includes an overview of the area, methods, data analysis, and evaluation.

From summary: This report describes work done in the Pueblo National Topographic Map Series (NTMS) quadrangle, Colorado, by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From introduction: This report describes work done in the Trinidad, Colorado, National Topographic Map Series (NTMS) quadrangle (US Geological Survey, 1955) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From summary: This data release presents analytical results obtained for a pilot study being done in portions of the Sterling and Greeley, Colorado, National Topographic Map Series (NTMS) quadrangles (Fig. 1) by the University of Colorado under contract to the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From introduction: This report describes work done in the Sterling, Colorado, National Topographic Map Series (NTMS) quadrangle (1:250 000 scale) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From introduction: This report describes work done in the Pueblo, Colorado, National Topographic Map Series (NTMS) quadrangle (1:250 000-scale) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From introduction: This report describes work done in the Denver and Greeley National Topographic Map Series (NTMS) quadrangles (1:250 000 scale) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

Abstract: Multivariate statistical analyses were carried out on Hydrogeochemical and Stream Sediment Reconnaissance data from the Craig quadrangle, Colorado, to support the National Uranium Resource Evaluation and to evaluate strategic or other important commercial mineral resources. A few areas for favorable uranium mineralization are suggested for parts of the Wyoming Basin, Park Range, and Gore Range. Six potential source rocks for uranium are postulated based on factor score mapping. Vanadium in stream sediments is suggested as a pathfinder for carnotite-type mineralization. A probable northwest trend of lead-zinc-copper mineralization associated with Tertiary intrusions is suggested. A few locations are mapped where copper is associated with cobalt. Concentrations of placer sands containing rare earth elements, probably of commercial value, are indicated for parts of the Sand Wash Basin.

Report describing chemical analysis of 62 water and 620 sediment samples during a follow-up geochemical survey to search for uranium in the Pueblo quadrangle.

From introduction: This report describes work done in the Durango National Topographic Map Series (NTMS) quadrangle, Colorado, by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From summary: The University of Colorado, under contract with the Los Alamos Scientific Laboratory (LASL), is currently performing an evaluation of geochemical relationships of water and sediments and seasonal variations to uranium for the South Platte drainage of northeastern Colorado. As a preliminary part of this study, samples were collected from 125 sites near Sterling and Fort Morgan, Colorado, during the period from December 20, 1976, to January 15, 1977. During this period the weather in the area was clear to partly cloudy, with daytime temperatures ranging from -12 to 12 C. Only a trace of precipitation, in the form of very light snow flurries, occurred during the sampling period. The sample site locations and numbers (the first two digits have been omitted) are shown on Plate I.

Report documenting the results of chemical analysis for 1518 water and 1604 sediment samples in the Durango quadrangle, Colorado. It includes an overview of the area, methods, data analysis, and evaluation.

Report documenting the results of chemical analysis for 1060 water and 1240 sediment samples in the Trinidad quadrangle, Colorado. It includes an overview of the area, methods, data analysis, and evaluation.

A report discussing HSSR results for the Leadville NTMS Quadrangle

A report discussing HSSR results for the eastern portion of the Montrose NTMS Quadrangle

This report provides uranium and other elemental data resulting from the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Craig quadrangle, Colorado.

A report characterizing known uranium occurrences in the Montrose Quadrangle and to find other areas in the quadrangle with similar characteristics

Color photographs of geologic maps, Landsat imagery, and density slices for the Montrose quadrangle, Colorado. Also included is a color composite for the COCH-1 classification scheme.