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Geology topics

F. J. Kleinhampl

Publications and source records attributed to F. J. Kleinhampl.

11 recordsLinked to original sources

Stratigraphy, structure, and geologic history of the Lunar Lake Caldera of northern Nye County, Nevada

The Lunar Lake caldera is in northern Nye County, Nev., about 70 mi (110 km) east-northeast of Tonopah. It is the youngest caldera in the central Nevada multiple-caldron complex and the source of the tuff of Lunar Cuesta, a multiple-flow simple cooling unit of quarts latitic welded tuff that is about 25 m.y. old. The tuff was distributed over an area of nearly 3,000 mi 2 (7,770 km 2 ) and has a volume of approximately 90 mi 3 (375 km 3 ). The Lunar Lake caldera is the site of the Lunar Crater basalt field which contains basalts of Pleistocene and probably Holocene age. These basalts were fed from northeast-trending fissures that had much earlier served as vents for ash-flow tuffs and lavas, possibly including the tuff of Lunar Cuesta.

Nevada

Botanical prospecting for uranium in the Circle Cliffs area, Garfield County, Utah

Astragalus pattersoni and Stanleya pinnata broadly define some uraniferous localities adjacent to the contact of the Moenkopi formation and the Shinarump member of the Chinle formation, but the general paucity of Astragalus in the Circle Cliffs area limits the usefulness of this genus. Astragalus pattersoni , Stanleya pinnata , and Aster venustus (?) may serve as guides to mineralized parts of the Salt Wash sandstone member of the Morrison formation in the Circle Cliffs area. Thick and thin sandstones of the Shinarump member generally can be distinguished by pinyon-juniper ration studies. These studies may supplement drilling to define channel-fill sandstones which are associated with ore deposits in the Circle Cliffs area. Ratio studies appear to be applicable to other areas throughout the Colorado Plateau where similar geological and ecological conditions exist.

Utah