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GWRP > Regional Groundwater Availability Studies Geospatial Data > Great Basin Carbonate
Great Basin Carbonate Aquifer System
The rocks and deposits of the Great Basin carbonate and alluvial aquifer system (GBCAAS) study area are grouped into hydrogeologic units that are inferred to have reasonably distinct hydrologic properties due to their physical characteristics. The hydrogeologic units for the GBCAAS study area include (1) a noncarbonate confining unit representing low-permeability Precambrian siliciclastic formations, (2) a lower carbonate aquifer unit representing high-permeability Cambrian through Devonian limestone and dolomite, (3) an upper siliciclastic confining unit representing low-permeability Mississippian shale, (4) an upper carbonate aquifer unit representing high-permeability Pennsylvanian and Permian carbonate rocks, (5) a thrusted noncarbonate confining unit representing low-permeability siliciclastic rocks incorporated in regional thrust faults, (6) a thrusted lower carbonate aquifer unit representing high-permeability limestone and dolomite incorporated in regional thrust faults, (7) a volcanic unit representing outcrop areas of volcanic rocks, (8) a lower basin-fill aquifer unit representing the lower one-third of the Cenozoic basin fill, and (9) an upper basin-fill aquifer unit representing the upper two-thirds of the Cenozoic basin fill.
The data files listed below are supplemental to the USGS Scientific Investigations Report 2010-5193 titled 'Conceptual model of the Great Basin carbonate and alluvial aquifer system.' This report includes a description of methods used to derive the data.
Click on the links below to download files (see Explanation of spatial data formats).