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Robert C. Greene

Publications and source records attributed to Robert C. Greene.

16 recordsLinked to original sources
USGS1995

Talc resources of the conterminous United States

Talc has been extracted from deposits in the United States for more than two centuries, some for dimension stone but most for ground talc products. This report is designed to summarize the current knowledge of the talc deposits and includes locations and descriptions of occurrences in 27 states, with emphasis on important producing districts. Permissive areas for additional deposits are shown and suggestions for exploration are given.

Alabama, Arkansas, California, Connecticut, Georgi↗
USGS1989

Mineral resources of the Mount Tipton Wilderness Study Area, Mohave County, Arizona

The Mount Tipton Wilderness Study Area (AZ-020-012/ 042) comprises 33,950 acres in Mohave County, Ariz. At the request of the U.S. Bureau of Land Management, this area was evaluated for identified mineral resources (known) and mineral resource potential (undiscovered). This work was carried out by the U.S. Bureau of Mines and the U.S. Geological Survey in 1984-87. In this report, the area studied is referred to as the "wilderness study area" or simply "the study area." There are no identified mineral resources in the study area. The southernmost part of the study area is adjacent to the Wallapai (Chloride) mining district and has low mineral resource potential for gold, silver, copper, lead, zinc, and molybdenum in hydrothermal veins. This area also has a low mineral resource potential for tungsten in vein deposits and for uranium in vein deposits or pegmatites. In the central part of the wilderness study area, one small area has low mineral resource potential for uranium in vein deposits or pegmatites and another small area has low resource potential for thorium in vein deposits. The entire study area has low resource potential for geothermal energy but no potential for oil or gas resources.

Arizona↗
USGS1983

Reconnaissance geology of the Al Ufayriyah quadrangle, sheet 20/42 A, Kingdom of Saudi Arabia

The Al Ufayriyah quadrangle is located in the Najd Plateau of southwestern Saudi Arabia between lat 20?30' and 21?00' N.,. long 42?00' and 42?30' E. Two-thirds of the quadrangle is underlain by Precambrian metasedimentary, metavolcanic, plutonic, and hypabyssal intrusive rocks; this area is in part mountainous and in part uneven plains. One-third is underlain by Cenozoic basalt and is part of Harrat Buqum. Flows, which surround volcanic cones, form an east-dipping surface of low relief. Precambrian metavolcanic and metasedimentary rocks are mostly metamorphosed andesite and basalt flow rocks and turfs and are divided into two principal belts in the eastern and central to western parts of the quadrangle. Plutonic rocks, which are part of the An Nimas batholith, consist of tonalite, diorite, and some quartz diorite. These rocks are postdated by younger plutonic and hypabyssal rocks that include extensive graphic granite and rhyolite, several small bodies of granite, and meta-andesite dikes. Volcanoes on Harrat Buqum are cinder cones, composite cones, shield volcanoes, and lava cones; basalt flows originating in some of the volcanoes can be traced down the slope of the harrat, and some have blocked Wadi Ranyah causing deposition of silt, sand, and gravel. Radiometric age dating of Precambrian rocks from adjacent quadrangles suggests that the layered rocks of the Al Ufayriyah quadrangle may have formed about 900 Ma ago, plutonic rocks of the An Nimas batholith 835 to 800 Ma ago, and younger plutonic rocks from 640 to 570 Ma ago. Basalts of Harrat Buqum range in age from 3.5 to 1.72 A zone in the eastern part of the quadrangle contains small gold-quartz veins, a quartz breccia reef, and a contact metasomatic iron deposit.

Open-File Report↗
USGS1983

Reconnaissance geology of the Jabal Dalfa Quadrangle, sheet 21/43 C, Kingdom of Saudi Arabia

The Jabal Dalfa quadrangle (sheet 21/43 C) is part of the Najd province in west-central Saudi Arabia. The quadrangle is mostly a plain, tilted gently northeastward, but local inselbergs and two areas of dissected uplands rise as much as 200 m above the plain. Wadi Bishah and Wadi Ranyah terminate in the quadrangle. The quadrangle is underlain by Precambrian metavolcanic, metasedimentary, and plutonic rocks. The gneiss outcrops in the northeast and east-central parts of the quadrangle are apparently the oldest rocks. After they were emplaced, a wide variety of metavolcanic and metasedimentary rocks were deposited at Jabal Dalfa and Umm Shat, and in the northeast part of the quadrangle as the Arfan formation. Subsequently, granite gneiss was emplaced in the west part of the quadrangle and intruded by gabbro. Metabasalt and meta-andesite were extruded in a wide north-trending belt through the middle of the quadrangle and at Jabal Silli. Intrusion of small bodies of granitic rocks and Najd faulting conclude the Precambrian history of the area. Surficial deposits include sand and gravel covering the plains, alluvial fans, and voluminous dune sands. In the southeast part of the quadrangle, the layered rocks strike north and dip steeply. They are oriented parallel to the Nabitah fault zone. In the northeast and east-central parts of the quadrangle, layered rocks and gneiss are sheared into slices by the southernmost faults of the major Najd fault zone. Bedding and foliation in these slices strike northwest, parallel to the faults. Gneiss in the west part of the quadrangle also strikes northwest, and dips steeply to vertically; layered rocks underlying Jabal Silli strike northeast. Layered metamorphic rocks in the Jabal Dalfa quadrangle are mostly in the greenschist facies. Projection of data from other quadrangles suggests that the oldest gneiss is about 780 Ma old and the Arfan formation, Umm Shat, and Jabal Dalfa layered rocks are about 775 to 745 Ma old. The gneiss of Shaib Hadhaq is probably about 720 Ma old, the gabbro is 640 to 625 Ma old, and the granite is about 600 Ma old. The airborne magnetometer survey suggests that considerable additional gabbro underlies the west part of the quadrangle. Concealed serpentinite bodies, particularly in the Nabitah fault zone, are also suggested. Elongate anomalies and linear gradients indicate that the northeast part of the quadrangle is probably part of the Najd fault zone. A number of gold-bearing quartz veins in the quadrangle were mined in ancient times, and on, at Jabal Umm Matirah has been drilled and found to be uneconomic. A nickel-copper prospect has proved uneconomic. geochemical survey for additional deposits of metals was completed in 1982.

Open-File Report↗
USGS1983

Reconnaissance geology of the Thaniyah Quadrangle, sheet 20/42 C, Kingdom of Saudi Arabia

The Thaniyah quadrangle, sheet 20/42 C, is located in the transition zone between the Hijaz Mountains and the Najd Plateau of southwestern Saudi Arabia between lat 20?00' and 20?30' N., long 42?00' to 42?30' E. The quadrangle is underlain by Precambrian metavolcanic, metasedimentary, plutonic, and dike rocks. Metavolcanic rocks consist of metamorphosed basalt and andesite with minor dacite and rhyolite and underlie three discontinuous northwest-trending belts. Metasedimentary rocks are confined to small areas underlain by quartzite, metasandstone, marble, and calc-silicate rock. Plutonic rocks include an extensive unit of tonalite and quartz diorite and a smaller unit of diorite and quartz diorite, which occupy much of the central part of the quadrangle. A small body of diorite and gabbro and a two-part zone of tonalite gneiss are also present. All of these plutonic rocks are assigned to the An Nimas batholith. Younger plutonic rocks include extensive graphic granite and rhyolite in the northeastern part of the quadrangle and several smaller bodies of granitic rocks and of gabbro. The metavolcanic rocks commonly have strong foliation with northwest strike and steep to vertical dip. Diorite and quartz diorite are sheared and brecciated and apparently syntectonic. Tonalite and quartz diorite are both foliate and nonfoliate and were intruded in episodes both preceding and following shearing. The granitic rocks and gabbro are post-tectonic. Trends of faults and dikes are mostly related to the Najd faulting episode. Radiometric ages, mostly from adjacent quadrangles, suggest that the An Nimas batholith is 835 to 800 Ma, gabbro and granite, except the graphic granite and rhyolite unit, are about 640 to 615 Ma, and the graphic granite and rhyolite 575 to 565 Ma old. Metavolcanic rocks similar to those hosting copper and gold mineralization in the Wadi Shuwas mining district adjacent to the southwestern part of the quadrangle are abundant. An ancient copper mine was discovered at the edge of the tonalite gneiss belt east of Wadi Ranyah. Granite and gabbro have economic potential as building stone.

Open-File Report↗
USGS1974

Mineral resources of proposed additions to the Salmon-Trinity Alps Primitive Area, California

A mineral survey of four areas totalling 80 square miles, not included during the 1968-70 examination of the proposed Salmon-Trinity Alps Wilderness, was made by the U.S. Geological Survey and U.S. Bureau of Mines in 1973. Geological Survey personnel mapped the geology and collected stream-sediment and rock samples for spectrographic and chemical analysis; Bureau of Mines personnel examined the known placer and lode claims. The areas examined include: (1) the upper drainage of Red Cap Creek in Humboldt County, adjoining the northwest part of the Salmon-Trinity Alps Primitive Area; (2) an area in Trinity County south of the Primitive Area including the drainage of Big French Creek and the canyon of North Fork Trinity River from Hobo Gulch Forest Camp to the junction with East Fork of North Fork; (3) an area, also south of the Primitive Area and in Trinity County, including East Fork of North Fork from Manzanita Flat to Squaw Gulch, and the drainages of Indian Creek, Squaw Gulch, lower East Branch, and lower Yellow Jacket Creek; (4) the drainage of St. Clair Creek in Siskiyou County north of the Primitive Area; and (5) a small area on New River from the junction of Slide and Virgin Creeks downstream to the mouth of Barron Creek that was previously mapped by the Geological Survey (Hotz and others, 1972) but had not been studied by the Bureau of Mines.

California↗