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Clay M. Conway

Publications and source records attributed to Clay M. Conway.

4 recordsLinked to original sources
USGS1990

Mineral Resources of the Wabayuma Peak Wilderness Study Area, Mohave County, Arizona

The Wabayuma Peak Wilderness Study Area (AZ-020-037/043), for which a mineral survey was requested by the U.S. Bureau of land Management, encompasses 40,118 acres in northwestern Arizona. Fieldwork was carried out in 1986-88 by the U.S. Bureau of Mines and the U.S. Geological Survey to appraise the identified (known) resources and assess the mineral resource potential (undiscovered) of the wilderness study area. Within the Wabayuma Peak Wilderness Study Area are 14 private parcels of land totaling 1,315 acres. The Wabayuma Peak Wilderness Study Area, including the 14 private parcels of land, is herein referred to as the 'wilderness study area' or the 'study area'. The Boriana, Antler, and Copper World mines lie near the east boundary of the study area. The Boriana mine was a major tungsten-producing mine of the United States during World War II. The Antler and Copper World mines produced relatively small amounts of copper and zinc prior to 1970. Copper and zinc were mined within 100 ft of the study area at the Antler mine. The Antler mine contains subeconomic resources of 350,000 to 400,000 short tons of copper-zinc ore; a minimum of 2,000 short tons, at grades of 1 to 4 percent copper and 1 to 2 percent zinc, lie within the study area. No other mineral resources were identified within the study area. Four small tracts in the eastern part and one in the central part of the study area have high resource potential for copper, zinc, and minor lead, silver, and gold in massive sulfide deposits. A large central tract and two eastern tracts have moderate resource potential for the same metals. An eastern and a western tract within the wilderness study area have high resource potential for tungsten, copper, and combinations of beryllium, gold, silver, arsenic, bismuth, molybdenum, tin, indium, thorium, niobium, yttrium, lanthanum, scandium, tantalum, rhenium, lead, zinc, and iron in granite-related tungsten-polymetallic vein deposits. Most of the rest of the study area has moderate resource potential for these metals. A northern tract in the study area has moderate resource potential for gold, copper, and combinations of silver, zinc, lead, tungsten, and molybdenum in polymetallic vein deposits of several types.

Bulletin↗
USGS1985

Geology and regional setting of the Al Masane ancient mine area, southeastern Arabian Shield, Kingdom of Saudi Arabia

Stratiform zinc-copper massive-sulfide deposits at Al Masane occur in thin dolomitic interbeds within Proterozoic felsic crystal tuff and mafic flows and volcaniclastics. These strata dip steeply westward and are underlain by shale and shaly graywacke to the east and overlain by lapilli crystal tuff to the west. This section is part of the Habawnah fold or mineral belt that extends from the Wadi Wassat area southward into Yemen. Western parts of the Habawnah fold belt, including the Al Masane area, are characterized by a bimodal assemblage of of phenocryst-poor basalts and sodic rhyolite crystal tuff, and by zinc-copper mineral deposits. Strata in the eastern part of the belt, mostly east of the Ashara fault zone, contain abundant phenocryst-rich mafic volcanic rocks, little felsic crystal tuff, and barren or locally nickeliferous massive pyrite deposits. Stratified rocks and gabbro sills of the Al Masane area were isoclinally folded and metamorphosed to the greenschist facies. Structural analysis indicates that foliation, lineation, joints, major and minor folds, and one of three sets of faults formed during a single east-west compressional deformational episode. Axial-plane foliation dips steeply westward and is usually coincident with bedding. Lineation plunges steeply to the northwest throughout the map area and is parallel to the intersection of joints of two major sets and to the intersection of these joints with foliation. Major folds have north-trending, gently plunging axes to which the axis of a minor fold set is essentially parallel. A second minor fold-set has a steeply plunging axis parallel to lineation. The Saadah massive-sulfide body is elongated by a fold of this system. Unmetamorphosed Proterozoic felsic sills, quartz monzonite and gabbro plutons, porphyritic diorite dikes, mafic dikes, and basalt dikes, in that apparent order, have intruded the stratified section. Basalt dikes are offset by southwestward-dipping reverse faults and by faults parallel to bedding. Malachite and metal-oxide-bearing gossans in the Al Masane area were mined in ancient times. Radiocarbon dating of charcoal in slag indicates that the ores were smelted about 1,200 years ago. Gossans are depleted in copper, silver, and zinc, relative to underlying sulfide, by factors of about 0.33, 0.2, and 0.08, respectively. Evaluation of numerous analyses of gossans, carbonates, and silicate rocks indicates that exploration for zinc-copper massive-sulfide deposits in the region should center on detailed geochemical studies of dolomitic beds. Dolomitization of host siliceous shales and tuffs and the formation of the massive-sulfide bodies at Al Masane probably caused by submarine fumarolic hydrothermal activity during periods of relative volcanic quiescence. Further work in the Al Masane region should include a study of the dolomitized areas and a search for other potential alteration "pipe" products (e.g. chlorite) as a guide to location of proximal deposits. Zinc-copper deposits at Al Masane and in the Dhahar-Al Hajrah and Kutam-Farah Garan areas have characteristics in common and are associated with felsic volcanic centers in the western bimodal part of the Habawnah mineral belt. They probably have parallel origins related to sea-floor volcanism. Deposits at Al Masane and Dhahar-Al Hajrah are possibly in the same general stratigraphic interval. Characteristics and distribution of altered rocks at Kutam suggest that the observed structural control of mineralization may represent remobilization. Chemical characteristics of volcanic rocks at Al Masane and elsewhere, along with features such as zinc-copper-iron sulfide mineralization, rhyolite-basalt bimodality, and the quartz phenocryst-rich nature of the felsic rocks, are compatible with an unusually primitive tholeiitic island-arc origin for the strata and mineral deposits of the Habawnah mineral belt.

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