Mineral resources of the Mecca Hills Wilderness Study Area, Riverside County, California

Content Provider	Semantic Scholar
Author	Morton, Douglas M. Kilburn, James E. Griscom, Andrew Campbell, Harry W.
Copyright Year	1988
Abstract	The part of the Mecca Hills Wilderness Study Area (CDCA343) for which mineral surveys were requested encompasses 9,490 acres in the northeast corner of the Salton Trough in southern California. Field work for this report was conducted in 1983 and 1985 by the U.S. Bureau of Mines and U.S. Geological Survey to assess the identified mineral resources (known) and the mineral resource potential (undiscovered) of the area. No metallic mineral resources were identified in the study area, nor were any current mining claims found. Oil and gas leases were present in 1983. The Skeleton Canyon mine, in the southwestern part of the study area, yielded clay to seal nearby irrigation canals, but does not currently constitute a resource. Areas within the San Andreas fault zone extending northwest and southeast from the clay deposit have moderate resource potential for clay. Undiscovered clay resources in this area are likely to be of little economic interest. The area southwest of the San Andreas fault has low potential for oi I and gas resources and the entire study area has moderate potential for low-temperature (less than 90°C) geothermal resources. The study area has low potential for barite and strontium resources. Character and Setting The Mecca Hills Wilderness Study Area is a badlands area of low but extremely rugged relief located at the north end of the Salton Trough, 13 mi southeast of Indio, Calif, (fig. 1). It is underlain by a basement of Proterozoic (see appendix for geologic time chart) gneiss and related rocks and the Mesozoic Orocopia Schist. The basement rocks are overlain mainly by a deformed sequence of upper Pliocene and Pleistocene nonmarine sedimentary rocks. The San Andreas fault crosses the southwestern part of the study area, where it cuts the Pliocene and Pleistocene Palm Springs Formation. Identified Resources All prospects within and near the study area were examined, and eight samples were collected and analyzed. There are no identified mineral resources in the study area. The only known mine within the study area is the Skeleton Canyon mine, which has a large tonnage of clay that could become a resource if a market were identified. This mine consists of bulldozer cuts from which clay was mined to seal irrigation canals (Crowell and Sylvester, 1979, p. 157). The clay is present as low hills of brick-red fault gouge within the San Andreas fault zone and contains fragments and blocks of siltstone and sandstone. The clay unit strikes N. 60° W. and dips about 30° ME. Exposures of the clay cover about 30 acres of which 20 acres are inside the study area. The clay zone is about 4,900 ft long and 50 to 100 ft thick. It pinches out to the southeast and is buried by alluvium on the northwest. Mineral Resource Potential There is no direct evidence that mineralizing events took place within the Mecca Hills Wilderness Study Area. The areas within the San Andreas fault zone northwest and Mineral Resources of the Mecca Hills Wilderness Study Area, Riverside County, California C1 southeast of the clay occurrence at the Skeleton Canyon mine have a moderate potential for clay resources, although undiscovered clay resources are unlikely to be economic. The area southwest of the San Andreas fault has low potential for oil and gas resources and the entire study area has moderate potential for low-temperature (less than 90 °C) geothermal resources. The study area has low potential for barite and strontium resources. INTRODUCTION This mineral survey was requested by the U.S. Bureau of Land Management and is a joint effort by the U.S. Geological Survey (USGS) and the U.S. Bureau of Mines (USBM). An introduction to the wilderness review process, mineral survey methods, and agency responsibilities was provided by Beikman and others (1983). The U.S. Bureau of Mines
File Format	PDF HTM / HTML
DOI	10.3133/b1710C
Alternate Webpage(s)	https://pubs.usgs.gov/bul/1710c/report.pdf
Alternate Webpage(s)	https://doi.org/10.3133/b1710C
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article