Lacustrine Diatomaceous Deposits of Piute Valley, California and Nevada: ABSTRACT

Abstract

A small, potentially economic deposit of diatomite occurs in Piute valley, near the California-Nevada border. Outcrops are found primarily in Secs. 21 and 28, T13N, R19E, San Bernardino Base and Meridian. The deposit crops out over an area of approximately 1 mi2 (2.6 km2). The materials consist of diatomite interbedded with minor amounts of sand, silt, and volcanic ash. The sediments are capped by a layer of caliche. The deposit has been gently uplifted and has been dissected by erosion to expose at least 15 ft (4.6 m) of diatomite and associated sediments. The deposit is lacustrine in origin. The entire deposit it thinly laminated with sand and silt lenses occurring mostly near the top. Predominantly diatomite occurs below this sequence. A cursory examination under the microscope showed approximately 80% diatomite. The beds dip either subhorizontal or 2 to 5° to the east in all occurrences. Microscopically, the majority of the diatoms are rodlike or cylindrical in shape, which is typical of lacustrine diatoms found in the southwest. The individual diatoms are intact and show little or no alteration. The material from the deposit has been used in the past as filler for wallboard and as insulation material. End_of_Article - Last_Page 1702------------