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Mining in the Fortymile District Alaska
Introduction: At the end of the field season the writer visited the mining plants in the Fortymile district, and this paper, resulting from these examinations, is intended mainly to sketch the present progress of mining development in the district.
Tertiary Deposits of the Eagle-Circle District, Alaska
From introduction: The present report aims to supply additional information regarding the Tertiary deposits, which are the source of most of the gold placers now being worked in that part of the Eagle-Circle district lying south of the Yukon River. The work was conducted from base camps along the river, but the belt of Tertiary rocks is at places as much as 20 miles from the Yukon, so that it is not easily accessible from the river except in the vicinity of mining camps, where roads or trails have been constructed southward.
Geology and Oil Resources of the Jonesville District, Lee County, Virginia
From abstract: The Jonesville district is in central Lee County in the extreme southwest corner of Virginia. It includes an area that is 25 miles long from northeast to southwest and averages 6 miles in width. Most of the district lies within a broad lowland named the Powell Valley, but the district includes Wallen Ridge, which bounds Powell Valley on the southeast.
The Fairhaven Gold Placers, Seward Peninsula, Alaska
From letter of transmittal: This manuscript is based on geologic and topographic reconnaissance survey, made during the summer of 1903, of an important placer-gold district in the northeastern part of Seward Peninsula.
Geology of the Chitina Valley and Adjacent Area, Alaska
From abstract: The Chitina Valley and adjoining area form part of a rugged alpine region in the southeast corner of the main body of Alaska and include a portion of the Chugach Mountains and most of the southern half of the Wrangell Mountains, to the north. The Chitina River is an eastern branch of the Copper River and rises in ice fields and valley glaciers occupying most of the country near the international boundary north of Mount St. Elias. The adjoining area described in this report includes the Hanagita and Bremner River district and the westward continuation of the north side of the Chugach Mountains as far as Valdez Arm and Klutina Lake. In addition, the geology of the upper White River district is described because of its relation to that of the Chitina Valley.
Geology of the Eastern Part of the Alaska Range and Adjacent Area
From abstract: This paper describes the geology of a part of the Alaska Range, extending from the Delta River to the international boundary between Alaska and Canada, and of an additional area that includes part of the Wrangell Mountains and the upper Copper River valley.
Geology of the Gerstle River District, Alaska, with a Report on the Black Rapids Glacier
From abstract: The area here described includes most of the north side of the Alaska Range between the Delta and Johnson Rivers, in one direction, and the axis of the Alaska Range and the Tanana River in the other. Besides the Delta River, its principal streams are Jarvis Creek, the Gerstle and Little Gerstle Rivers, and, at the extreme east, the Johnson River, all of which have glacial sources.
Geology of the Prince William Sound Region, Alaska
From introduction: This paper describes the geology of the Prince William Sound region, a part of south-central Alaska. It deals with the rocks of a section of the Coast Ranges that has been studied by various geologists over a period of many years and still offers basic problems that are unsolved. Prince William Sound is well known for its mining activities, but the intention here is to describe the areal and stratigraphic geology of the district rather than its mineral resources and to present a statement that will serve as a report of progress and a basis for more detailed field work.
Geology of the Upper Tetling River District Alaska
From introduction: This paper describes the geology of a part of the Alaskan Range that lies in the headwater region of the Copper and Tanana Rivers.
Notes on the Geology of Upper Nizina River Alaska
Introduction: It is not intended to give here a full account of the geology of the district but rather to present certain new features that were observed during the season, with enough of the general geology, which is already well known and fully described in other publications, to make them understandable.
Mineral Resources of Kenai Peninsula, Alaska
From introduction: This report details the mineral resources of Kenai Peninsula.
Middle Cretaceous Stratigraphy on the South and East Sides of the Uinta Basin, Northeastern Utah and Northwestern Colorado
From abstract: Middle Cretaceous rocks (Aptian to Coniacian) on the south side of the Uinta Basin include the nonmarine Cedar Mountain Formation and Dakota Sandstone and the lower part of the overlying marine Mancos Shale. This report examines the rocks contained within this area of the basin.
The Frontier Formation and Associated Rocks of Northeastern Utah and Northwestern Colorado
From abstract: The Frontier Formation of the Mancos Group in northeastern Utah and northwesternmost Colorado (proposed new rank designations; formerly known as the Frontier Sandstone Member of the Mancos Shale) consists of several facies of marine and nonmarine rocks of Late Cretaceous (Turonian) age that grade eastward into totally marine rocks in easternmost Utah and northwestern Colorado.
Manganese Deposits of Cedar Creek Valley, Frederick and Shenandoah Counties, Virginia
From abstract: The Cedar Creek manganese mining district is in the southwestern part of Frederick County and the northwestern part of Shenandoah County, Virginia. The manganese ore consists chiefly of the oxides pyrolusite and psilomelane, and forms replacement pockets and fracture fillings in the Oriskany sandstone and in residual sandy clay and chert derived from the New Scotland limestone. Both these formations are of Devonian age, and both form low ridges. The minable bodies have been deposited by ground water in the zone of weathering, and most of them lie above present ground-water level. The manganese-bearing formations, together with the older and younger formations exposed in Cedar Creek Valley, have been compressed into numerous folds, and at the southwestern end of the district one of these folds passes into a normal fault with a displacement of 1,000 feet or more.
Mineral Resources of the Clover Mountains Wilderness Study Area, Lincoln County, Nevada
From abstract: At the request of the U.S. Bureau of Land Management, approximately 84,165 acres of the Clover Mountains Wilderness Study Area (NV-050-139) was evaluated for mineral resources (known) and mineral resource potential (undiscovered). In this report, the area studied is referred to as "the wilderness study area" or simply "the study area;" any reference to the Clover Mountains Wilderness Study Area refers only to that part of the wilderness study area for which a mineral survey was requested by the U.S. Bureau of Land Management. The study area is located in southern Nevada, in Lincoln County, about 90 mi northeast of Las Vegas. No identified mineral resources exist inside the study area, although gold, silver, and copper resources are found immediately to the west at the Pennsylvania mine.
Geochemical Signatures of Silver and Gold Deposits, Tonopah 1° x 2° Quadrangle, Nevada: Description and Applications to Exploration
The following report presents geochemical data results of 34 elements in 951 samples of altered and mineralized rock samples from mines, prospects, dumps, and drillholes in the Tonopah quadrangle, Nevada.
Geology and Geochemistry of Tertiary Volcanic Host Rocks, Sleeper Gold-Silver Deposit, Humboldt County, Nevada
The following report focuses on the geology of the Tertiary volcanic rock formation in the Sleeper gold-silver deposit of Nevada and develops a framework for exploration and genetic models.
Bedrock Geology of the Paducah 1°x2° CUSMAP Quadrangle, Illinois, Indiana, Kentucky, and Missouri
The following report interprets the geologic history of the Paducah quadrangle, focusing on depositional and tectonic evolution, particularly tectonic events that influenced sedimentation.
Mineral Resources of the Fort Piute Wilderness Study Area, San Bernardino County, California
From abstract: The Fort Piute Wilderness Study Area (CDCA-267) is in northeastern San Bernardino County, California, near the boundary between California and Nevada. Mineral surveys were requested for 31,371 acres of the Fort Piute Wilderness Study Area. In this report the area studied is referred to as "the study area". Examination of mines and prospects in the area was accomplished by the U.S. Bureau of Mines in 1981 and 1982. Field investigations of the area were carried out by the U.S. Geological Survey in 1983 and 1985. No mines or prospects, few mining claims, and no identified resources are located within the wilderness study area. Moderate and low potential for gold resources appears limited to outcrops of gneiss and granite exposed along the eastern side of the Piute Range. Available information indicates that there is no potential for energy resources, including oil and gas, uranium, or geothermal, in the study area.
Significant Metalliferous Lode Deposits and Placer Districts of Alaska
From preface: "This report is a compilation of the significant metalliferous lode deposits and placer districts of Alaska, and is a comprehensive data base for a companion article on the metallogenesis and major mineral deposits of Alaska that will be published in the volume of Alaskan geology for the Decade of North American Geology (DNAG) by the Geological Society of America."
Burial and Thermal History of the Paradox Basin, Utah and Colorado, and Petroleum Potential of the Middle Pennsylvanian Paradox Formation
From abstract: This is a report on the burial and thermal history of the Paradox basin in Utah and Colorado, and the petroleum potential of the middle Pennsylvanian Paradox Formation.
[Evolution of Sedimentary Basins--Uinta and Piceance Basins: Chapters H and I]
From abstract: Analysis of vitrinite reflectance profiles and surfaces of equal vitrinite reflectance in the southeastern part of the Piceance basin, northwestern Colorado, indicates that burial histories for the Divide Creek anticline and the Grand Hogback are different from those for adjacent synclines. These two positive structures probably reached their present-day thermal maturity before late Eocene folding and before the end of the Laramide orogeny. In contrast, adjacent synclines did not reach their present-day thermal maturity until the end of the Laramide orogeny, or possibly later.
Mineral Resources of the Deep Creek Mountains Wilderness Study Area, Juab and Tooele Counties, Utah
From abstract: The Deep Creek Mountains Wilderness Study Area (UT-020-060/UT-050-020) includes most of the Deep Creek Range of west-central Utah. The area is near the Utah-Nevada State line, south of Wendover, Utah, and northwest of Delta, Utah. Eleven areas of mineralized rock in and near the study area were evaluated by the U.S. Bureau of Mines. Four of these areas contain identified resources: (1) an indicated resource of 5,000 short tons of 16.5 ounces silver per short ton, 4.1 percent lead, 4.6 percent zinc, and 0.25 percent copper, at the Willow Springs area, which is almost surrounded by the study area in the northeast corner although it is not part of the study area; (2) an indicated gold resource of 774,000 short tons of 0.4 ounces per short ton and an inferred gold resource of 5.7 million short tons of 0.4 ounces per short ton in the Goshute Canyon area immediately east of the study area; (3) an indicated gold resource of 75,000 short tons of 0.22 ounces per short ton in the Queen of Sheba mine just west of the study area; and (4) an inferred gold resource of 3,800 short tons of 0.26 ounces per short ton in the Gold Bond area immediately east of the study area.
Adsorbent Clays: Their Distribution, Properties, Production, and Uses
From Abstract: "This bulletin is a summary of present knowledge of the adsorbent or bleaching clays-their distribution, field and laboratory identification, physical and chemical properties, uses, quality, and value. Problems in the drying, treating with acids, and washing are discussed, and methods of testing and rating decolorizing efficiency are described."
Geomorphic, Seismic, and Geotechnical Evaluation of Sand and Gravel Deposits in the Sheridan, Wyoming, Area
The following report analyzes the geomorphic setting, the use of seismic-refraction data to delineate buried deposits, and the geotechnical analysis of aggregate samples of the sand and gravel deposits in Sheridan, Wyoming.
Mica-Bearing Pegmatites of New Hampshire: a Preliminary Report
From abstract: Mica has been mined in New Hampshire since 1803. Production from 1908 through 1939 has aggregated 13,326,990 pounds of sheet and punch mica, an annual average of 416,470 pounds. Since 1931 production has been below this average, because of economic conditions rather than depletions. The mica-bearing pegmatites of the Grafton and Keene districts occur mostly in sillimanite-mica schist adjacent to large areas of biotite gneiss. The pegmatite bodies range from a fraction of an inch to more than 200 feet in thickness; most of them are crosscutting, and about 75 percent strike northeast. Mica occurs sporadically in most of them but where present in commercial quantities it is localized in one or more of the following zones: (1) In quartz-plagioclase-muscovite zones 2 to 10 feet from the walls of large pegmatite bodies, (2) in or near quartz masses that occur mostly near the centers of the bodies, (3) in thin dikes 5 to 15 feet thick or in similar offshoots from larger bodies, (4) within large pegmatite bodies, in more or less tabular streaks or zones composed principally of plagioclase, quartz, and muscovite.
Distribution of Benthic Foraminifers (>125 µm) in the Surface Sediments of the Arctic Ocean
A report which discusses the distribution of benthic foraminifers in surface sediment samples from 49 box cores collected by the U.S. Geological Survey.
Tin and Tungsten Deposits at Silver Hill, Spokane County, Washington
From abstract: Tin and tungsten minerals occur in pegmatites and quartz veins at Silver Hill, in secs. 23 and 24, T. 24 N., R. 43 E., 11 miles southeast of Spokane, Wash.
Mineral Resources of the Llano-Burnet Region, Texas with an Account of the Pre-Cambrian Geology
The following report examines the mineral resources and geologic relations of the pre-Cambrian rocks and the associated iron ores in the Llano-Burnet region, Texas.
Manganese Resources of the Olympic Peninsula, Washington: a Preliminary Report
Abstract: The northern, eastern, and southern parts of the Olympic Peninsula, Wash., contain many small deposits of manganese. Most of the deposits consist of complex manganese silicates with some carbonates, although 16,275 tons of hausmannite (Mn304) ore was mined at the Crescent mine during 1924-26. About a hundred tons of silicates have been mined from various properties, mainly for experimental purposes. Future production probably will not be large, because the silicate ores are of low grade and are difficult and expensive to treat. Moreover, most of the deposits are difficult of access, and most of the ore bodies are small isolated lenses and thin tabular bodies. The deposits are mostly in red limestone or red argillite near contacts with basalt, but a few of them are in basalt.
Mineral Resources of the Honeycomb Buttes Wilderness Study Area, Fremont and Sweetwater Counties, Wyoming
From summary: This report includes field investigations to evaluate the mineral resource potential of the Honeycomb Buttes were conducted during the summer of 1984. Geologic mapping, geochemical sampling, geophysical surveys, stratigraphic and sedimentological studies, and surveys of prospects delineated areas of very low grade placer gold deposits in terrace gravels and low and moderate resource potential for additional similar undiscovered placer gold deposits, low and moderate resource potential for small uranium deposits, moderate resource potential for accumulation of oil and gas, and low resource potential for coal and oil shale.
Mineral Resources of the Behind the Rocks Wilderness Study Area, Grand and San Juan Counties, Utah
Abstract: The Behind the Rocks Wilderness Study Area (UT-060-140A) consists of 12,635 acres in Grand and San Juan Counties, Utah. The study area has inferred subeconomic resources of potash and halite in the subsurface, and sandstone on the surface. The study area has high potential for undiscovered resources of oil and gas, low potential for undiscovered uranium, copper, vanadium, gold, silver, other metals, and geothermal energy, and unknown potential for the rare-earth mineral, braitschite. There is no resource potential for potash or halite (beyond the previously mentioned inferred resources) or for coal.
Mineral Resources of the Indian Creek, Bridger Jack Mesa, and Butler Wash Wilderness Study Areas, San Juan County, Utah
From abstract: The Indian Creek (UT-060-164), Bridger Jack Mesa (UT-060-167), and Butler Wash (UT-060-169) Wilderness Study Areas are located in San Juan County, southeastern Utah. Inferred subeconomic resources of sandstone and sand and gravel exist within all three wilderness study areas, but because of their abundance throughout the region, their distance from current markets, and their lack of unique properties, these materials have no current likelihood for development.
Mineral Resources of the Farlin Creek Wilderness Study Area, Beaverhead County, Montana
Abstract: The Farlin Creek Wilderness Study Area (MT-076-034) is in the south-central Pioneer Mountains about 24 miles west-northwest of Dillon, Beaverhead County, southwestern Montana. At the request of the U.S. Bureau of Land Management, an area of 610 acres (less than 1 square mile) was investigated by the U.S. Geological Survey and the U.S. Bureau of Mines in 1984. The area contains no mines or prospects, no visible evidence of mineralization, and no identified mineral resources. Geophysical evidence suggests that three parts of the area have moderate mineral resource potential for undiscovered resources of molybdenum. The entire area has a low resource potential for all other metals and for all nonmetals, fuels, and geothermal energy.
Nickel-Copper Deposits on the West Coast of Chichagof Island, Alaska
From abstract: On the west coast of Chichagof Island, southeastern Alaska, are three nickel-copper deposits that consist of norite containing the sulfide minerals pyrrhotite, pentlandite, and chalcopyrite. The deposits are within less than a mile of each other and are, by water, 160 miles southwest of Juneau and 70 miles northwest of Sitka. The norite is part of a stock, about 5 square miles of which is above sea level. Other rocks of the stock are amphibolite, amphibolitic norite, gabbro, diorite, quartz diorite, monzonite, granite, pegmatites, quartz veins, and schist inclusions. The stock is intrusive into a Lower Cretaceous (?) graywacke formation and an Upper Triassic (?) greenstone formation, both of which are now metamorphosed to schist.
Nickel Deposit Near Riddle, Douglas County, Oregon
From Introduction: "The Riddle nickel deposit is on Nickel Mountain, also called Piney Mountain, about 5 miles northwest of Riddle, Douglas Country, Oreg. (fig. 20). The deposit is an unevenly distributed surficial blanket, containing the nickel silicate garnierite, which rests upon peridotitic rocks on the western, southern, and southeastern slopes of the mountain above an elevation of 2,000 feet. It is on the Southern Pacific Railroad, and it is about 230 miles by highway south of Portland. A poorly conditioned dirt road about 5 miles long connects the town with the nickel deposit."
Effect of Permafrost on Cultivated Fields, Fairbanks Area, Alaska
From introduction: This report describes the destructive effect of permafrost on cultivated fields and delineates the parts of the Fairbanks area which are least suitable for agriculture because of the character of the underlying permafrost. Studies by the author indicate that agriculture will be affected by similar permafrost conditions throughout areas on the north side of the Tanana Valley within 100 miles of Fairbanks.
Petrography, Mineralogy, and Reservoir Characteristics of the Upper Cretaceous Mesaverde Group in the East-Central Piceance Basin, Colorado
From abstract: Three closely spaced wells drilled through the Upper Cretaceous Mesaverde Group and were extensively cored and logged in order to identify the factors controlling the occurrence and distribution of gas in low-permeability rocks and to improve recovery technology.
Mineral Resources of the Mancos Mesa Wilderness Study Area, San Juan County, Utah
This report analyzes the Mancos Mesa Wilderness Study Area in San Juan County that contains low mineral resource potential for other metals, coal, and geothermal energy.
Late Paleozoic Structure of the Southern Part of the Uinta Basin, Utah, From Seismic Reflection Data
From abstract: Seismic reflection data from the southern part of the Uinta basin near Price, Utah reveal a network of late Paleozoic faults that produced abrupt variations in stratigraphic thicknesses in a structurally complex 30-mi-wide northwest-southeast-trending trough.
Regional Potential of Selected Paleozoic Carbonate Units in the Northern Midcontinent for Undiscovered Mississippi Valley-Type Deposits
From abstract: This report attempts to identify areas where geologic conditions for the Mississippi Valley-type (MVT) deposits are favorable.
The Yukon-Tanana Region, Alaska: Description of Circle Quadrangle
From preface: In planning the surveys and investigations of Alaska, the attempt was made to cover first those regions which were of the greatest economic importance.
The Gold Placers of the Fortymile, Birch Creek, and Fairbanks Regions, Alaska
From letter of transmittal: This report contains the economic results of a reconnaissance of these gold fields of the Yukon basin which was carried out in 1903.
Methods and Costs of Gravel and Placer Mining in Alaska
From letter of transmittal: It is believed that this report will stimulate the mining industry by making available, in compact form, the accumulated results of the experience of mining men in this field and by directing attention to those mining methods developed in older districts which appear to be adapted to the conditions prevailing in Alaska.
The Willow Creek Gold Lode District Alaska
From abstract: The gold quartz veins of the Willow Creek district belong to the type of ore deposits that may be expected to continue downward for several thousand feet below the present surface. The veins occur in an essentially homogeneous quartz diorite intrusive mass, batholithic in form ; therefore, the composition of the wall rock plays practically no significant part in the distribution of gold within the veins. The veins were formed partly as fissure fillings and partly by replacement of the wall rock along fractures and of fragments of wall rock caught between the fracture walls. Structurally the deposits are essentially composite lodes, although quartz lenses of considerable size have also been formed.
The Mount Eielson District Alaska
From abstract: The Mount Eielson district lies in south-central Alaska, on the north side of the Alaska Range, about 30 miles east of Mount McKinley. The most widely distributed rocks of the district include a thick series of thin-bedded limestone, calcareous shale, and graywacke of Paleozoic, probably Devonian, age. These sediments are cut by a mass of granodiorite which forms most of Mount Eielson and which was intruded probably in late Mesozoic time. The intrusive has sent a multitude of dikes and sills into the associated sediments.
Nickel-Copper Deposit at Funter Bay, Admiralty Island, Alaska
From abstract: The nickel-copper deposit near the north end of Admiralty Island, about 18 miles in an airline west of Juneau, in southeastern Alaska, consists of a basic sill which averages somewhat more than 100 feet in thickness. The sill, which dips eastward, is intrusive into a thick sequence of phyllite and various types of schist. The rock of the sill consists principally of the silicate minerals labradorite and olivine, but it also contains magnetite and the sulfides pyrrhotite, pentlandite, and chalcopyrite. It assays, on the average, about 0.34 percent nickel and 0.35 copper, which are doubtless mostly in the pentlandite and chalcopyrite respectively but are probably constituents of other minerals also. A significant proportion of nickel and copper is probably contained in the olivine and perhaps in the pyrrhotite.
Nickel Deposits of Bohemia Basin and Vicinity, Yakobi Island, Alaska
From Introduction: "According to present knowledge, the deposits center principally, in three areas: Bonemia Basin on Yakobi Island, Mirror Harbor on Chicagof Island, and Snipe Bay on Baranof Island. This report deals only with the deposits of the most northerly area, in and near Bohemia Basin."
Nickel-Copper Deposit at Snipe Bay, Baranof Island, Alaska
Abstract: At Snipe Bay, on the outer coast of Baranof Island, about 46 miles southeast of Sitka in southeastern Alaska, is a nickelcopper deposit that consists of a mass of basic rock intruded into quartzite and quartz schist. Neither the size nor the grade of the deposit is adequately known. Natural exposures and those in a few prospect openings indicate that to an assumed depth of about 130 feet below the lowest point on the outcrop there is a reserve of about 430,000 tons of low-grade nickelbearing material, which, to judge from available assays and from comparison with similar material from other places, probably does not contain more than 0.3 percent each of nickel and copper. The deposit thus appears too small and of too low grade to permit the recovery of the nickel and copper except at a considerable financial loss; but as the location is favorable for largescale, low-cost development, further prospecting may be justified, in the hope that a moderate amount of surface stripping, plus a few diamond-drill holes, might indicate that the deposit is larger, and possibly of higher grade, than it is safe to infer from the available data.
Geology of the Mount McKinley Quadrangle, Alaska
From abstract: The Mount McKinley quadrangle, in south-central Alaska, includes parts of the Alaska Range, the Tanana and Kuskokwim lowlands, and the Kuskokwim Mountains. Schists of Precambrian age crop out in the northern foothills of the Alaska Range. Sedimentary and volcanic rocks of Paleozoic and Mesozoic age are exposed in the Kuskokwim Mountains, where little is known of their distribution and character, and in the Alaska Range, where they occupy the axial part and northern limb of a great synclinorium. Granitic batholiths, largely of Mesozoic age, intrude the Paleozoic and Mesozoic rocks in the Alaska Range.
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