DOCUMENT


Classification of the California Desert for Geology-Energy-Mineral Resource Potential: Geostatistical Classification

Lands in the California Desert Conservation Area (CDCA) were classified according to their potential for geology-energy-mineral (G-E-M) resources using geostatistical techniques and an expert panel. The CDCA comprises over 100,000 square kilometers in southeastern California. All available reports of G-E-M occurrences in the CDCA were collected. Data on the 3,146 occurrences include location, commodity, name and, in some cases, geologic environment and production history. Forty geological variables represented on the Geologic Map of California; one geophysical variable (Bouguer gravity) and 20 lineament variables from each of four sources (LANDSAT imagery, Bouguer gravity contours, and aerial and Skylab photography) were recorded on a cell-by-cell basis over the entire CDCA. Data were encoded in numerical form for 26,810 cells (each 2 km by 2 km square). Three tonal anomaly variables and 30 geochemical variables were also recorded on a cell-by-cell basis for subareas of the CDCA where these data are available. Data recorded in this fashion, plus the data on G-E-M occurrences, served as the basis for statistically classifying cells according to likelihood of mineral occurrence. Cells so classified are 4 km by 4 km (an aggregate of four of the smaller 2 km x 2 km cells). Gamma-ray spectrometric (bismuth, thallium, potassium, bismuth to thallium ratio) and aeromagnetic data were also recorded on a cell-by-cell basis for use by the expert panel. Discriminant function analysis (DFA) is the statistical method used to classify the cells. The cells of the CDCA are classified with respect to the potential for gold deposits; iron deposits; manganese deposits; tungsten deposits; combined copper, zinc, lead, and silver deposits; and combined metals deposits. Occurrence data on over 40 other mineral commodities including sand and gravel, limestone, carbon dioxide, and geothermal fluid, were tabulated. Results are presented in tabular form and in map form. The maps show contours of mineral potential for each of the five commodity categories classified.

Document Type / Category
Technical Note
Document Collection
BLM Library
State/Office
National Office
Author
Lambie, F. W., et al.
Publication Date
1983
Science Subject