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USGS1978

United States Geological Survey uranium and thorium resource assessment and exploration research program, fiscal year 1979

After expansion of the USGS (U.S. Geological Survey) uranium-thorium program in FY (fiscal year) 1975, new directions of research could be pursued, particularly in sedimentology or genetic stratigraphy, geochemistry-mineralogy, and geophysics. In a relatively short time, many of the new research projects have developed critical information on uranium habitats and improved methods of exploration. In FY 1979 a budget increase of approximately 20 percent is programmed, for a funding base of $6,600,000. The increase is scheduled for research grants and contracts outside the USGS in order to extend the basic program without additional personnel. This outside research will be designed not only to increase basic information on uranium occurrence but also to aid the USGS in its evaluation of uranium favorability in key resource areas for the NURE (National Uranium Resource Evaluation) program of DOE (U.S. Department of Energy).

Open-File Report↗
USGS1979

Chemical analyses of coal from the Emery and Ferron Sandstone members of the Mancos Shale, Henry Mountains Field, Wayne and Garfield counties, Utah

As part of a continuing program by the U.S. Geological Survey to collect and chemically analyze representative samples of U.S. coals, 18 samples were collected from the Upper Cretaceous Emery and Ferron Sandstone Members of the Mancos Shale in the Henry Mountains coal field, Wayne and Garfield Counties, Utah (fig. 1). The 18 samples are briefly described in table 1. Thirteen of these samples were collected from seven holes that were drilled in connection with the Henry Mountains EMRIA (Energy Mineral Rehabilitation Inventory and Analyses) study (U.S. Department of the Interior, 1978). The locations of the seven core holes and the four other sampling sites are shown on figure 2. The Henry Mountains coal field is adjacent to the Henry Mountains of southeastern Utah. The basin is a long, narrow syncline about 110 km long and 24 km wide bounded on the west by the Waterpocket Fold and on the east by the Henry Mountains. The most comprehensive geologic report available on the area is by Hunt and others (1953). Their work included a considerable amount of information on the coal resources. Other work in the area concerning coal or stratigraphy of coal bearing units includes: Doelling (1972), Peterson and Ryder (1975), Doelling (1975), Law (1977; 1978; 1979 a,b), and U.S. Department of the Interior (1978). In the Henry Mountains field, there are three coal bearing units in rocks of Late Cretaceous age. In ascending order they are the Dakota Sandstone, the Ferron Sandstone Member of the Mancos Shale, and the Emery Sandstone Member of the Mancos Shale. The coal beds of the Henry Mountains coal field originated as layers of peat that were deposited, for the most part, in coastal swamp environments. Individual coal beds are discontinuous and exhibit large variations in thickness and quality. The thickest and most continuous coal beds occur in the Emery Sandstone Member along or near the axis of the Henry Mountains syncline (Law, 1978).

Utah↗
USGS1979

Analytical and stratigraphic data on the upper phosphatic mudstone member of the Santa Margarita Formation at Newsome Canyon, southern Cuyama Valley, California

A detailed stratigraphic and geochemical program was conducted in 1978 on the strata of the upper phosphatic mudstone member of the Santa Margarita Formation at Newsome Canyon, Santa Barbara County, California, (fig 1). This program was undertaken to determine the phosphate content of each stratigraphic unit in an area of complex stratigraphy and structure. The report includes a detailed stratigraphic description of the upper phosphatic member with location of samples collected (Table 1) and a tabulation of chemical analysis for each sample (Tables 2 and 3). The chemical data indicate the marine apatite (carbonate fluorapatite) is of variable composition.

California↗
USGS1979

Geology and physiography of the continental margin north of Alaska and implications for the origin of the Canada Basin

The continental margin north of Alaska is of Atlantic type. It began to form probably in Early Jurassic time but possibly in middle Early Cretaceous time, when the oceanic Canada Basin of the Arctic Ocean is thought to have opened by rifting about a pole of rotation near the Mackenzie Delta. Offsets of the rift along two fracture zones are thought to have divided the Alaskan margin into three sectors of contrasting structure and stratigraphy. In the Barter Island sector on the east and the Chukchi sector on the west the rift was closer to the present northern Alaska mainland than in the Barrow sector, which lies between them. In the Barter Island and Chukchi sectors the continental shelf is underlain by prisms of clastic sedimentary rocks that are inferred to include thick sections of Jurassic and Neocomian (lower Lower Cretaceous) strata of southern provenance. In the intervening Barrow sector the shelf is underlain by relatively thin sections of Jurassic and Neocomian strata derived from northern sources that now lie beneath the outer continental shelf. The rifted continental margin is overlain by a prograded prism of Albian (upper Lower Cretaceous) to Tertiary clastic sedimentary rocks that comprises the continental terrace of the western Beaufort and northern Chukchi Seas. On the south the prism is bounded by Barrow arch, which is a hingeline between the northward-tilted basement surface beneath the continental shelf of the western Beaufort Sea and the southward-tilted Arctic Platform of northern Alaska. The Arctic platform is overlain by shelf clastic and carbonate strata of Mississippian to Cretaceous age, and by Jurassic and Cretaceous clastic strata of the Colville foredeep. Both the Arctic platform and Colville foredeep sequences extend from northern Alaska beneath the northern Chukchi Sea. At Herald fault zone in the central Chukchi Sea they are overthrust by more strongly deformed Cretaceous to Paleozoic sedimentary rocks of Herald arch, which trends northwest from Cape Lisburne. Hope basin, an extensional intracontinental sedimentary basin of Tertiary age, underlies the Chukchi Sea south of Herald arch.

Open-File Report↗
USGS1979

Resource report for proposed OCS lease sale 57: Norton Basin, Alaska

This report is a summary of information about an area of the northern Bering Sea continental shelf that is bounded by the Seward Peninsula on the north, by the line of the United States-Russia Convention of 1867 on the west, and by St. Lawrence Island and the coastline that rims Norton Sound on the south and east. Scholl and Hopkins (1969) report that a sedimentary basin underlies the offshore area. More recent data, which form the basis of part of this report, show the basin is deepest beneath Norton Sound; also, the basin has sufficient depth and areal extent that the basin may be a target for development of hydrocarbon resources after Outer Continental Shelf (OCS) Lease Sale 57. The informal, but widely used, name for the basin is Norton Basin. The following discussion includes regional geology, geologic history, and offshore structure and stratigraphy as background data to discussion of the hydrocarbon potential and resource appraisal of the offshore area. Sections on environmental geology and on the technology and manpower needed and available for development of offshore resources are also included.

Alaska↗
USGS1979

Ice gouge obliteration and sediment redistribution event: 1977-1978, Beaufort Sea, Alaska

In 1978 major changes in shelf morphology were observed during a routine re-survey of part of the inner shelf region of the central Beaufort Sea. Regional observations are coupled with a detailed diving and side-scan study of a single ice gouge of known age to develop a detailed description of the altered seabed conditions. Hydrodynamic activity has caused extensive sediment reworking, obliterating ice gouges to water depths of at least 13 m and has caused ponding of sediment in ice gouge terrain in deeper waters. Ponded sediment is characterized as a soft, sometimes very poorly consolidated, mud unit underlain by a stiffer, more consolidated, silty clay. In places, stiff silty clay is exposed in windows in the sediment pond and displays a fine-textured ice gouge morphology. Rates of sediment reworking and redisposition from apparently episodic events are an order of magnitude greater than the average sediment accumulation rates on the Beaufort Sea shelf. Reported maximum ice gouge incision depths are not representative of maximum ice keel penetrations into the seabed because these sedimentation events preferentially infill gouges. Furthermore, because these sedimentation events concentrate sediments in gouge troughs, a series of overlapping and interfingering 'shoestring' deposits is developed which should characterize the ice gouge stratigraphy. The specific hydraulic mechanisms for sediment redistribution and sediment compaction observed in this study are only poorly understood.

Open-File Report↗
USGS1980

Bibliography of fine-grained siliceous deposits

This bibliography was compiled under the auspices of the International Geologic Correlations Project's (IGCP) Research Group 115, "Siliceous Deposits of the Pacific Region"; IGCP is sponsored by UNESCO and the International Union of Geological Sciences (IUGS). Research Group 115 was originally proposed to IGCP in 1974 by Professor Azuma Iijima, University of Tokyo, and is now headed by James R. Hein, U.S. Geological Survey. Cooperative efforts by 86 members from 17 countries help in accomplishing Research Group 115's objectives of correlating sedimentary processes of siliceous deposits in the Pacific Basin and neighboring geosynclinal areas by means of stratigraphy, sedimentology, geochemisty, and paleontology. These correlations will allow us to estimate the geochemical silica budget in the Earth's crust; to estimate the production of silica in the marine environment through geologic time; to formulate a general rule on sedimentation of siliceous deposits in geosynclines; to increase understanding of the development of circum-Pacific orogenic belts; and to obtain basic methods to evaluate siliceous deposits of economic interest. The group agreed to focus on fine-grained siliceous deposits (cherts, siliceous shales, diatomites, and the like) and to exclude quartz sand deposits and quartzose sandstones.

Open-File Report↗
USGS1980

Graded storm sand layers offshore from the Yukon Delta, Alaska

The northern Bering Sea has a history of severe storm surges. The most recent, and perhaps the worst in historical times, occurred in November, 1974 (Fathauer, 1975). Evidence of storm surge events is exhibited in sea-floor stratigraphy as well as shoreline flooding and indicates that significant widespread changes in sea-floor sedimentation take place (Nelson and Creager, 1977). These changes have implications for installations on the sea floor and for mass transport of pollutants. This paper describes the interbedded sand layers found in southern Norton Sound off the modern Yukon Delta that are deposited by the storm surge events. Such deposits are evident in both modern and ancient deposits of epicontinental shelves (Hays, 1967; Howard and Reineck, in press; Anderton, 1976.). These graded sand layers in very shallow water mimic many of the features of thin-bedded turbidite sands, although the shallow water deposits are thought to have a very different mechanism of deposition related to storm surge processes. Two factors in the oceanographic setting of northern Bering Sea magnify the effects of storm surge. The sea floor is very shallow (less than 20 m deep over wide areas) particularly in Norton Sound. Consequently there is intensive wave reworking which causes extensive sea-floor erosion, mass movement, displacement, and offshore progradation of significant amounts of sediment during storm surges; The second factor is a system of strong dynamic_ bottom currents that can move large amounts of sediment northward to Chukchi Sea during normal weather. Much more sediment is moved when the current is reinforced by relaxing of the sea surface set-up caused by storm surge (Fig. 1) (Flemming and Heggarty, 1966; Coachman et al., 1976; Cacchione and Drake, 1979; Schumacher and Tripp, 1979). Another important influence on the sedimentation in southern Norton Sound is the effect of seasonal processes on the Yukon River delta, During the winter months from November to May the Yukon River averages 40,000 cfs when the ice-covered river is fed mainly by base flow (Dupre, 1976). Within less than a week of river breakup, peak discharges may reach 1,000,000 cfs or more and then decline throughout the summer.

Alaska↗
USGS1981

Reconnaissance of the Hot Springs Mountains and adjacent areas, Churchill County, Nevada

A geologic reconnaissance of the Hot Springs Mountains and adjacent areas, which include parts of the Brady-Hazen and the Stillwater-Soda Lake Known Geothermal Resource Areas, during June-December 1975, resulted in a reinterpretation of the nature and location of some Basin and Range faults. In addition, the late Cenozoic stratigraphy has been modified, chiefly on the basis of radiometric dates of volcanic rocks by U.S. Geological Survey personnel and others. The Hot Springs Mountains are in the western part of the Basin and Range province, which is characterized by east-west crustal extension and associated normal faulting. In the surrounding Trinity, West Humboldt, Stillwater, and Desert Mountains, Cenozoic rocks overlie ' basement ' rocks of the Paleozoic and Mesozoic age. A similar relation is inferred in the Hot Springs Mountains. Folding and faulting have taken place from the late Tertiary to the present. (USGS)

Nevada↗
USGS1981

Measured sections of the Browns Park Formation (Miocene) in Moffat County, Colorado, 1980

Eight partial sections of the Browns Park Formation of Miocene age were measured in Moffat County, northwestern Colorado, during the 1980 field season, as part of a study of the stratigraphy and depositional environments of the formation. These newly measured sections are intended to complement other surface sections of the Browns Park Formation measured (Hansen, 1965) to the west in Uintah County, Utah, and measured (Buffler, 1967) or diagrammed (Kucera, 1968) to the east in, respectively, Routt and Rio Blanco Counties, Colorado. Rock samples collected, indicated parenthetically by 80-SL prefixes, are shown in the section descriptions purely for reference purposes; petrographic and analytical results will be reported in later publications. Color names with numbers are based on comparison with the rock-color chart by Goddard and others (1948). Field investigations were supported by the National Uranium Resource Evaluation (NUKE) program of the Grand Junction Office, U. S. Department of Energy, under contract No. DE-A113-78GJ01686.

Colorado↗
USGS1981

Data file: the 1976 Atlantic Margin Coring (AMCOR) Project of the U.S. Geological Survey

In 1976, the U.S. Geological Survey conducted the Atlantic Margin Coring Project (AMCOR) to obtain information on stratigraphy, hydrology and water chemistry, mineral resources other than petroleum hydrocarbons, and geotechnical engineering properties at sites widely distributed along the Continental Shelf and Slope of the Eastern United States (Hathaway and others, 1976, 1979). This program's primary purpose was to investigate a broad variety of sediment properties, many of which had not been previously studied in this region. Previous studies of sediments recovered by core drilling in this region were usually limited to one or two aspects of the sediment properties (Hathaway and others, 1979, table 2). The AMCOR program was limited by two factors: water depth and penetration depth. Because the ship selected for the program, the Glomar Conception , lacked dynamic positioning capability, its anchoring capacity determined the maximum water depth in which drilling could take place. Although it was equipped to anchor in water 450 m deep and did so successfully at one site, we attmepted no drilling in water depths greater than 300 m. Strong Gulf Stream currents at the one attempted deep (443 m) site frustrated attempts to "spud in" to begin the hole.

Open-File Report↗
USGS1982

Eruptive history, petrology, and petrogenesis of the Joe Lott Tuff Member of the Mount Belknap Volcanics, Marysvale volcanic field, west-central Utah

The Joe Lott Tuff Member of the Mount Belknap Volcanics is the largest rhyolitic ash-flow tuff sheet in the Marysvale volcanic field. It was erupted 19 m.y. ago, shortly after the changeover from intermediate-composition calc-alkalic volcanism to bimodal basalt-rhyolite volcanism. Eruption of the tuff resulted in the formation of the Mount Belknap Caldera whose pyroclastic intracaldera stratigraphy parallels that in the outflow facies. The Joe Loft Tuff Member is a composite ash-flow sheet that changes laterally from a simple cooling unit near the source to four distinct cooling units toward the distal end. The lowest of these units is the largest and most widespread; it is 64 m thick and contains a basal vitrophyre. Eruption of the lower unit led to the initial collapse of the caldera. The lower unit is followed upward by a 43 m middle unit, a 26 m pink-colored unit which is separated by a prominent air- fall layer, and a 31 m upper unit. The Joe Loft Tuff Member is an alkali rhyolite with 75.85-77.31 wt. % silica and 8.06-9.32 wt. % K2O+Na2O; the agpaitic index (Na2O+ K2O/Al2O3) is .77-.98. The tuff contains about I% phenocrysts of quartz, sanidine, oligoclase, augite, apatite, zircon, sphene, biotite, and oxidized Fe-Ti oxides. The basal vitrophyre contains accessory allanite, chevkinite, and magnesiohastingsite. The main cooling units are chemically and mineralogically zoned indicating that the magma chamber restratified prior to each major eruption. Within each of the two thickest cooling units, the mineralogy changes systematically upwards; the Or content and relative volume of sanidine decreases and An content of plagioclase increases. The basal vitrophyre of the lower unit has a bulk composition that lies in the thermal trough near the minima of Or-Ab-Q at 1 kb PH2O. Microprobe analyses of feldspar and chemical modeling on experimental systems indicate that pre-eruption temperatures were near 750?C and that the temperature increased during the eruption of the cooling units. The chemical gradients in the apatite and whole-rock data in the Joe Loft Tuff Member and the consistent mineral assemblages throughout the ash-flow cannot be explained by crystal settling. The fractionation of the Joe Lott Tuff Member appears to closer fit the model of convection-driven thermogravitational diffusion.

Open-File Report↗
USGS1983

High-Resolution Seismic Profile and Sidescan-Sonar Data Collected During June 1980 Offshore New Jersey, Whitefoot Cruise 80-1

This survey (888 km), of the New Jersey nearshore area, extended between Corson Inlet to the south and Mlanasquan Inlet to the north and from about 8 m depth to about 25 m depth. The lines were located between latitudes 39° and 40°10'N and longitudes 73°50' and 74° 40'W. High-resolution seismic­reflection data were collected using an EG&G Uniboom (400-4000 Hz) and an ORE Mode! 1035 (3.5 kHz) subbottom profiling system in conjunction with a Klein Sidescan Sonar System (100 kHz). While the quality of the data is variable, it is virtually all usable and generally of good quality but rarely excellent. Due to equipment failure, only 880 km of 3.5 kHz and 796 km of sidescan-sonar data were recorded. Navigation was by Loran-C. and fixes were recorded at 5-minute time intervals with some gaps in the data. Analysis of the sidescan-sonar data shows five recognizable features in the study area. Megaripples (2-3 m crestal spacing) were recorded almost exclusively on coast parallel tracklines, and were most abundant at distances of 10 to 20 km offshore. Nonlinear light and dark patches were abundant in the northern half of the study area and offshore to the south. Two groups of linear light and dark bands were observed as being clearly parallel or oblique to the bathymetric contours and were noted throughout the survey area. Trawl marks were noted on only one line near the shore, just north of Barnegat Inlet. These observations indicate widespread, perhaps frequent, movement of the surface sands on the Inner New Jersey continental shelf. Directions of sediment transport are suggested by the orientation of the alternating light and dark bands and the ripples, assuming a parallel and/or transverse relative movement. Asymmetry of the ripples was not observed on the sidescan sonographs. The high-resolution seismic-reflection profiles indicate three distinct types of subbottom stratigraphy in the top 20 to 40 m of sediment. Reflectors in the area north of Barnegat Inlet dip gently (<1° ) to the south-southeast. The thirty plotted reflectors are 5 to 12 m apart (vertically), are essentially parallel, and are truncated on the updip (northern) limits where they outcrop or subcrop (under a 2-4 m overburden). Truncated by erosion, they are the dominant cause of N65° east-striking topographic ridges in this offshore region. The age of the reflectors is· inferred to be Tertiary from the strike and dip, which are the same as the Tertiary beds of adjacent New Jersey.

Open-File Report↗
USGS1984

Geologic and hydrologic data collected during 1976-1983 at the Sheffield low-level radioactive waste disposal site and adjacent areas, Sheffield, Illinois

Hydrogeologic studies were conducted at the low-level radioactive-waste disposal site near Sheffield, Illinois, from 1976-84. Data in this report include water levels in wells, lake stages, inorganic, organic, and radiometric chemical analyses of ground and surface water, hydraulic conductivities of glacial materials, grain-size distribution, clay and carbonate mineralogy, and cation exchange capacities of the glacial materials. Also included are results of petrographic analyses, physical measurements of wells, stratigraphy and lithology of cores collected from test wells, and horizontal coordinates of wells.

Open-File Report↗
USGS1984

Brief statement on the hydrology of the Sampit River area near Georgetown, South Carolina

The Carolina Refining and Distributing Company is planning to locate an oil-refining plant near Georgetown, South Carolina. To aid in the preparation of an environmental impact statement, a description of the stratigraphy, ground-water resources, and an assessment of possible seismic activity that may occur in the Winyah Bay vicinity has been prepared. Additional data will be required to quantitatively evaluate the impact of an oil spill on the shallow aquifer in the area. (USGS)

South Carolina↗
USGS1987

Debris flows from tributaries of the Colorado River, Grand Canyon National Park, Arizona

A reconnaissance of 36 tributaries of the Colorado River indicates that debris flows are a major process by which sediment is transported to the Colorado River in Grand Canyon National Park. Debris flows are slurries of sediment and water that have a water content < 40% by volume. Debris flows occur frequently in arid and semiarid regions. Slope failures commonly trigger debris flows, which can originate from any rock formation in the Grand Canyon. The largest and most frequent flows originate from the Permian Hermit Shale, the underlying Esplanade Sandstone of the Supai Group, and other formations of the Permian and Pennsylvanian Supai Group. Debris flows have reached the Colorado River on an average of once every 20 to 30 yr in the Lava-Chuar Creek drainage since about 1916. Two debris flows have reached the Colorado River in the last 25 yr in Monument Creek. The Crystal Creek drainage has had an average of one debris flow reaching the Colorado River every 50 yr, although the debris flow of 1966 has been the only flow that reached the Colorado River since 1900. Debris flows may actually reach the Colorado River more frequently in these drainages because evidence for all debris flows may not have been preserved in the channel-margin stratigraphy. Discharges were estimated for the peak flow of three debris flows that reached the Colorado River. The debris flow of 1966 in the Lava-Chuar Creek drainage had an estimated discharge of 4,000 cu ft/sec. The debris flow of 1984 in the Monument Creek drainage had a discharge estimated between 3,600 and 4,200 cu ft/sec. The debris flow of 1966 in the Crystal Creek drainage had a discharge estimated between 9,200 and 14,000 cu ft/sec. Debris flows in the Grand Canyon generally are composed of 10 to 40% sand by weight and may represent a significant source of beach-building sand along the Colorado River. The particle size distributions are very poorly sorted and the largest transported boulders were in the Crystal Creek drainage. Reworking of debris fans by the Colorado River creates debris bars that constrain the size of eddy systems and forms secondary rapids and riffles below tributary mouths. (See also W89-09239) (Lantz-PTT)

Arizona↗
USGS1990

Geology of the Mahd Adh Dhahab District, Kingdom of Saudi Arabia

Approximately 200 km 2 around the Mahd adh Dhahab mine were mapped at 1:18,000 scale, with emphasis on establishing the volcanic stratigraphy. The Mahd Group, which rests over a basement of metamorphosed tonalite, is divided into the Lahuf formation and Tuwal formation, which are separated by an unconformity. The Lahuf is divided into a lower felsic pyroclastic member, a middle felsic tuff member, and an upper mafic member. The overlying Tuwal formation is divided into the Mine member, which consists predominantly of subaqueous felsic pyroclastic rocks with minor dolostone and chert, and the Ghuwayshat member, which consists predominantly of subaerial ignimbrites. The Mahd Group also contains numerous basaltic and rhyolitic subvolcanic intrusions, some of which were extruded as lava flows. The Mahd Group was folded, intruded by rocks of the Ramram cauldron, and eroded prior to deposition of the overlying Ghamr group. Remnants of the latter consist of fanglomerate, volcaniclastic sediments, and dacitic lava flows. Burial of the region under rocks of the Ghamr group probably accounts for prehnite-pumpelleyite facies metamorphism. Vein mineralization at Mahd adh Dhahab and other occurrences is probably unrelated to the magmatism that produced the Mahd and Ghamr groups. The Wadi Sayilah-Wadi Ghadayrah fault system was active during deposition of the Mahd and Ghamr groups and accounts for about 2.6 km of cumulate uplift of the basement block relative to the Mahd basin. Major-element data show that the Mahd Group was produced from separate basaltic and dacitic-rhyolitic magmas that overlapped without mixing. The alkalis and alkaline-earth elements were particularly mobile during metamorphism (which caused widespread albitization of feldspars) and also during hydrothermal alteration (which added secondary microcline). This mobility adversely affected rubidium-strontium whole-rock systematics, which makes whole-rock isochron dates obtained from these rocks questionable. The new geological data presented here are combined with the geochronologic data of Calvez and Kemp (1982) to re-interpret the geologic history of this area.

Open-File Report↗
USGS1993

Construction, lithologic, and hydrologic data for test wells in the Cedar Grove area, Carroll County, Tennessee

Four test wells were drilled near Cedar Grove in Carroll County, Tennessee, in 1991 to obtain geologic and hydrologic information about the post-Cretaceous strata in the study area. Samples of cuttings and geophysical logs were used to determine the lithology and stratigraphy at the drilling sites. Specific-capacity tests and water-quality analyses were conducted at two test wells completed in the Memphis Sand. Yields of the two test wells were 275 gallons per minute and greater than 350 gallons per minute. The specific capacities for the two wells equalled 17.8 and 10.0 gallons per minute per foot of drawdown, respectively.

Tennessee↗