Correlation and origin of carnotite occurrences in the southern Nevada region

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1982

OSTI ID:6937929

Johnson, C L

Carnotite (K/sub 2/(UO/sub 2/)/sub 2/(VO/sub 4/)/sub 2/.3H/sub 2/O) is recognized at seven localities in the southern Nevada region. These general areas of occurrence are the Jean-Sloan Calcrete, Hidden Valley Calcrete, Hualapai Limestone, Boulder City ''fossil water table'', Horse Spring Formation type locality, Mormon Mesa Caliche, and exposures of the Willow Tank thrust fault. The carnotite occurrences pre-date the 3.80 MY (million years before present) basalt at Sandy Pint, post-date an 8.66 MY tuff that underlies the Hualapai Limestone, and are approximately coeval with the 5.84 MY Fortification Basalt. Analysis of the Th/U ratios from 2045 dry stream sediment samples collected during the National Uranium Resource Evaluation (NURE) Program indicates uranium depletion in Precambrian terrain of the region and enrichment in areas where carnotite is observed. Anomalous vanadium in dry stream sediment samples is associated with intermediate and mafic Cenozoic volcanic rocks of pre-Colorado River age, and to a lesser extent with uratic Precambrian rocks. Correlation of the Jean-Sloan Calcrete, Hidden Valley Calcrete, Mormon Mesa Caliche, Hualapai Limestone, and Boulder City ''fossil water table'' is proposed based on elevation, relief, and inferred common age and origin. Carnotite studies have provided recognition criteria for facies of a regional geomorphic surface that formed in association with sluggish shallow groundwater flow in axial drainage systems in the Late Miocene. Carnotite and gypsum were deposited in disrupted by normal faulting and climatic conditions become increasingly arid 5-6 MY ago. Major geologic events that approximately coincide with the formation of the carnotite occurrences include the Messinian Crisis, opening of the Gulf of California, and uplift of the Sierra Nevada.

• OSTI ID: 6937929
• Country of Publication: United States
• Language: English

Related Subjects

050100* -- Nuclear Fuels-- Reserves
Exploration
& Mining
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
ACTINIDE COMPOUNDS
ACTINIDES
ALKALINE EARTH METAL COMPOUNDS
BASALT
CALCIUM COMPOUNDS
CALCIUM SULFATES
CARBONATE ROCKS
CARNOTITE
CHEMICAL ANALYSIS
DRAINAGE
ELEMENTS
FEDERAL REGION IX
GEOCHEMICAL SURVEYS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GROUND WATER
GYPSUM
HYDROGEN COMPOUNDS
IGNEOUS ROCKS
ISOTOPE RATIO
LIMESTONE
MATERIALS
METALS
MINERALS
NEVADA
NORTH AMERICA
OXYGEN COMPOUNDS
PRECAMBRIAN ERA
QUANTITATIVE CHEMICAL ANALYSIS
RADIOACTIVE MATERIALS
RADIOACTIVE MINERALS
RESERVES
RESOURCES
ROCKS
SEDIMENTARY ROCKS
SULFATE MINERALS
SULFATES
SULFUR COMPOUNDS
SURVEYS
THORIUM
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
URANIUM
URANIUM COMPOUNDS
URANIUM MINERALS
URANIUM RESERVES
URANIUM VANADATES
USA
VANADATES
VANADIUM
VANADIUM COMPOUNDS
VOLCANIC ROCKS
WATER
WATER TABLES