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Contours of Corcoran Clay Depth in feet from Page (1986) for the Central Valley Hydrologic Model (CVHM)

Metadata Updated: April 6, 2024

This digital dataset defines the depth of the Corcoran Clay Member of the Tulare Formation. The complex hydrologic system of the Central Valley is simulated using the USGS numerical modeling code MODFLOW-FMP (Schmid and others, 2006b). This simulation is referred to here as the Central Valley Hydrologic Model (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. Numerous lenses of fine-grained sediments are distributed throughout the southern Central Valley (San Joaquin Valley) and generally constitute more than 50 percent of the total thickness of the valley fill. Generally, these lenses are discontinuous and not vertically extensive or laterally continuous. However, the Corcoran Clay is a low-permeability, areally extensive, lacustrine deposit (Johnson and others, 1968) as much as 200-ft thick (Davis and others, 1959; Page, 1986). This continuous clay divides the groundwater-flow system of the western San Joaquin Valley into an upper semi-confined zone and a lower confined zone (Williamson and others, 1989; Belitz and Heimes, 1990; Burow and others, 2004). The extent and distribution of the Corcoran Clay was defined for use in the CVHM because the unit is one of the few deposits in the Valley that can be regionally mapped. The CVHM is the most recent regional-scale model of the Central Valley developed by the U.S. Geological Survey (USGS). The CVHM was developed as part of the USGS Groundwater Resources Program (see "Foreword", Chapter A, page iii, for details).

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date April 6, 2024

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date April 6, 2024
Publisher U.S. Geological Survey
Identifier USGS:2eedd7e1-0522-465f-9478-c47e5263a46e
Data Last Modified 20201117
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 61c9adc5-b1c8-43e1-918d-b35e81548b55
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -121.504203,35.004248,-118.758069,37.793811
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash d2b0f26fa0c7dd7c64d1e9ba1e1e08a53e6b7cef904f3ff4d655916340aac1f6
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -121.504203, 35.004248, -121.504203, 37.793811, -118.758069, 37.793811, -118.758069, 35.004248, -121.504203, 35.004248}

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