Percent Coarse in wells in 15 meter increments and Texture Model Percent Coarse at Lattice Points for the Central Valley from Faunt (2009)

This digital dataset contains the percentage of coarse-grained deposits in wells in 15 meter increments 
and the percentage of coarse-grained deposits in texture model lattice points interpolated from the well 
data for the Central Valley. The texture model was used as input data for the hydraulic properties portion 
of the Central Valley Hydrologic Model (CVHM).  The Central Valley encompasses an approximate 50,000 
square-kilometer region of California. The complex hydrologic system of the Central Valley is simulated 
using the U.S. Geological Survey (USGS) numerical modeling code MODFLOW-FMP (Schmid and others, 
2006).  This simulation is referred to here as the CVHM (Faunt, 2009). Utilizing MODFLOW-FMP, the 
CVHM simulates groundwater and surface-water flow, irrigated agriculture, land subsidence, and other key 
processes in the Central Valley on a monthly basis from 1961-2003.  The total active modeled area is 20,334 
square-miles on a finite-difference grid comprising 441 rows and 98 columns. Slightly less than 50 percent 
of the cells are active. The CVHM model grid has a uniform horizontal discretization of 1x1 square mile and 
is oriented parallel to the valley axis, 34 degrees west of north (Faunt, 2009). In order to better characterize 
the aquifer-system deposits, lithologic data from approximately 8,500 well-drillers logs of boreholes ranging 
in depth from 12 to 3,000 feet below land surface were compiled and analyzed. The percentage of coarse-grained 
sediment, or texture, then was computed from this classification for each 50-foot depth interval of the driller's 
logs. A 3D texture model was developed by interpolating the percentage of coarse-grained deposits onto a 1-mile 
spatial grid at 50-foot depth intervals from land surface to 2,800 feet below land surface. The CVHM is the most 
recent regional-scale model of the Central Valley developed by the USGS.  The CVHM was developed as part 
of the USGS Groundwater Resources Program (see "Foreword", Chapter A, page iii, for details).

Tags: alameda-county, amador-county, butte-county, calaveras-county, california, central-valley, central-valley-aquifer, central-valley-california, central-valley-hydrologic-model, colusa-county, contra-costa-county, cv-rasa, deposit, el-dorado-county, flow-model-cvhm, fresno-county, geostatistics, glenn-county, groundwater, groundwater-availability-of-the-central-valley-aquifer, humboldt-county, hydrogeology, hydrology, inlandwaters, kern-county, kings-county, lake-county, madera-county, mariposa-county, mendocino-county, merced-county, model, monterey-county, napa-county, nevada-county, placer-county, sacramento-county, sacramento-valley, san-benito-county, san-joaquin-county, san-joaquin-valley, san-luis-obispo-county, santa-barbara-county, santa-clara-county, shasta-county, solano-county, sonoma-county, stanislaus-county, sutter-county, tehama-county, texture-model, trinity-county, tulare-county, tuolumne-county, unconsolidated-sediments, usgs-a53bb527-441b-4d84-af83-48a84339d829, ventura-county, yolo-county, yuba-county
Organization: Department of the Interior