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Articles 27601 - 27630 of 29955

Full-Text Articles in Geology

Annual Outflow/Inflow Of Water From Nebraska, 1950-1985, Conservation And Survey Division Jan 1986

Annual Outflow/Inflow Of Water From Nebraska, 1950-1985, Conservation And Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Late Prehistoric And Protohistoric Large Mammal Zoogeography Of Virginia, Robert K. Rose Jan 1986

Late Prehistoric And Protohistoric Large Mammal Zoogeography Of Virginia, Robert K. Rose

Biological Sciences Faculty Publications

Evidence derived from18late prehistoric (middle and late Woodland Period) archeological sites, from several early historical accounts, and from the current understanding of the distribution of Virginia mammals indicates that the large mammal fauna of the Commonwealth has not changed substantially within the past 4,000 yrs. Some species (e.g., bison, elk, timber wolf, and mountain lion) have been extirpated since the settlement of Virginia by Europeans; some previously extirpated species (e.g., porcupine, coyote, and beaver) have been naturally or artificially reintroduced during the historical period, and others (e.g., woodchuck and red fox) probably have expanded their distributions as a result of …


Deflation Basin Stratigraphy: Southwestern North Dakota, Robert E. Seidel Jan 1986

Deflation Basin Stratigraphy: Southwestern North Dakota, Robert E. Seidel

Theses and Dissertations

The goal of this study was the determination of a similar depositional sequence for sediments from a number of shallow basins in southwestern North Dakota and the comparison of this sequence with other work either in the area or in similar geographic environments.

Samples were obtained by augering, coring, and trenching selected basins. They were analyzed by means of: core description; detailed texture analyses on selected cores by sieve, pipette, and SediGraph techniques; and mineralogy by x-ray diffraction. Computer analyses were used to characterize grain-size distributions and to correlate texture and mineralogy by cross-association.

The results of the study verified …


Contaminant Migration Of Oil-And-Gas Drilling Fluids Within The Glaciated Sediments Of North-Central North Dakota, William A. Beal Jan 1986

Contaminant Migration Of Oil-And-Gas Drilling Fluids Within The Glaciated Sediments Of North-Central North Dakota, William A. Beal

Theses and Dissertations

A common practice during oil and gas well-site reclamation in North Dakota is to bury the drilling muds in shallow trenches near the borehole. These muds are saltwater based (between 100,000 and 300,000 mg/L of NaCl) and can contain high concentrations of chromium, lead, and other. toxic trace metals.

Two reclaimed oil and gas well sites were chosen for study in north-central North Dakota: the Winderl site in southeastern Renville County, and the Fossum site in west-central Bottineau County. The Winderl oil well was drilled in 1959, and the drilling fluids were disposed of in a shallow pit excavated in …


The Structural Controls Of The Vale Rhinehart Buttes Complex, Vale Kgra, Malheur County, Oregon, John Timothy Doerr Jan 1986

The Structural Controls Of The Vale Rhinehart Buttes Complex, Vale Kgra, Malheur County, Oregon, John Timothy Doerr

Dissertations and Theses

The Vale KGRA is characterized by high heat flow, two to five times higher than the worldwide average, and by numerous hot springs. The hot springs are aligned along faults. This phenomena is typical of a Basin and Range type geothermal system. The hot geothermal fluids migrate upward along the more permeable, fault planes.

The rocks exposed in the Vale area are the Pliocene Chalk Butte formation and the Pleistocene beds of Captain Keeney Pass. Both units are composed of volcaniclastic siltstones, sandstones and conglomerates. The units are differentiated by color, texture and degree of lithification. About 200 meters of …


The Stratigraphy And Structure Of The Columbia River Basalt Group In The Salmon River Area, Oregon, Martin S. Burck Jan 1986

The Stratigraphy And Structure Of The Columbia River Basalt Group In The Salmon River Area, Oregon, Martin S. Burck

Dissertations and Theses

Approximately 16 km of Columbia River basalt are exposed in the Salmon River area to the south and to the west of Mount Hood, Oregon. A maximum composite basalt section composed of 15 flows and totaling 461 m is exposed in discontinuous areas of outcrop.

The Columbia River basalt in the Salmon River area belongs to the Grande Ronde Basalt and the Frenchman Springs Member of the Wanapum Basalt. The Grande Ronde Basalt section (6 flows) was mapped as two chemically distinct units referred to as low-MgO (older) and high-MgO (younger) Grande Ronde Basalt. At least …


Geology, Hydrology And Hydrogeochemistry Of The West Brush Creek Development Area, Beulah Mine, Mercer County, North Dakota, Gary D. Winbourn Jan 1986

Geology, Hydrology And Hydrogeochemistry Of The West Brush Creek Development Area, Beulah Mine, Mercer County, North Dakota, Gary D. Winbourn

Theses and Dissertations

The West Brush Creek Development Area, a part of the Beulah Mine, occupies a rolling upland approximately 7 kilometres southwest of Beulah in west-central North Dakota. This study describes the geology, hydrology, and hydrogeochemistry of an 8 km2 area which is scheduled for strip mine development, and addresses the potential impacts of mining on the local hydrologic and hydrogeochemical regime.

Four previously recognized stratigraphic intervals in the Paleocene Sentinel Butte Formation were described and correlated. They are, from oldest to youngest, the Spaer, Beulah-Zap, Schoolhouse and Twin Buttes intervals, each named for the lignite bed which caps the interval. The …


Shoreline Recession: Past, Present, And Future, Lake Sakakawea, North Dakota, Brian S. Sandberg Jan 1986

Shoreline Recession: Past, Present, And Future, Lake Sakakawea, North Dakota, Brian S. Sandberg

Theses and Dissertations

Shoreline erosion is a major problem at Lake Sakakawea, North Dakota. Instrumentation along the eastern shore was initiated in 1983 to measure shoreline recession and determine the processes responsible, with the ultimate goal being the development of a relatively simple equation to predict the rate of recession which is better than the model currently used by the U.S. Army Corps of Engineers.

For the twenty stations, the present rate of recession ranges from 0.2 to 4.3 m/y. Approximately 78 percent of the yearly recession occurs during the warm months (May-October) due to wave erosion. Erosion over the cold months occurs …


Depositional History And Diagenesis Of The Upper Mission Canyon And Lower Charles Formations (Mississippian), Billings County, North Dakota, Randall A. Stephens Jan 1986

Depositional History And Diagenesis Of The Upper Mission Canyon And Lower Charles Formations (Mississippian), Billings County, North Dakota, Randall A. Stephens

Theses and Dissertations

The upper Mission Canyon and lower Charles Formations of the Madison Group (Mississippian) in central Billings County, North Dakota respectively consist of interbedded limestones and dolostones, and anhydrite. Study of these rocks was limited to Big Stick and T.R. Fields, located on the Billings Anticline, central Williston Basin.

Detailed examinations of cores from a 166 ft (51 m) section within the upper Mission Canyon and lower Charles Formations resulted in the identification of seven lithotypes: echinoderm wackestone-packstone, dolomudstone, dolomitic echinoderm wackestone, grainstone, skeletalpeloidal carbonate, laminated carbonate, and anhydrite. The stratigraphic distribution of lithotypes is consistent throughout the study area.

Deposition …


Geology Of The Escalante District, Iron County, Utah, James William Biehl Jan 1986

Geology Of The Escalante District, Iron County, Utah, James William Biehl

Masters Theses

"The Escalante Silver District, Iron County, Utah, occupies a group of low hills extending to the Escalante Desert from the Black Hills to the south. Tertiary volcanics serve as host rocks for silver bearing quartz veins. Five map units, with a total of 12 members are recognized. X-ray fluorescence and field mapping enabled differentiation of the units, while thin section analysis enabled characterization of the members. The map units formed in three episodes. The oldest is extrusive doming of distinctive older lava and breccia flows. The middle group is made up of tectontic breccias, sillar-like lava flows, and volcaniclastic sediments …


Glacial Deposits, Vol. 14, 1985-1986, Department Of Geography-Geology Jan 1986

Glacial Deposits, Vol. 14, 1985-1986, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Petrology, Mineralogy, And Geochemistry Of The Goldlund Gold Deposit, Northwestern Ontario, Steven D. Giddings Jan 1986

Petrology, Mineralogy, And Geochemistry Of The Goldlund Gold Deposit, Northwestern Ontario, Steven D. Giddings

Theses and Dissertations

The Goldlund Mine is located in the Wabigoon Sub province of the Canadian Shield. Although the mine has been open sporadically since the late 1930's, little is known about the geochemistry and petrography of the deposit. The purpose of this study was to use petro-graphic, geochemical, and physical data to document and better understand the host rock, alteration, and mineralization of the deposit, and to develop a generalized model of formation.

Results showed that the host rocks of the gold mineralization are albitized tonalite dikes. Gold, in native form and in gold-silver tellurides, occurs in quartz veins and in adjacent …


Conodont Biostratigraphy Of The Bakken And Lower Lodgepole Formations (Devonian And Mississippian), Williston Basin, North Dakota, Timothy P. Huber Jan 1986

Conodont Biostratigraphy Of The Bakken And Lower Lodgepole Formations (Devonian And Mississippian), Williston Basin, North Dakota, Timothy P. Huber

Theses and Dissertations

Fourteen cores were sampled and processed, and conodonts obtained were used in the biozonation of the Bakken and basal Lodgepole Formations in the Williston Basin in North Dakota. The Bakken Formation of Devonian and Mississippian age and the Lodgepole Formation, entirely of Mississippian age, are subsurface units in North Dakota. The Bakken Formation (44 metres thick) consists of, in ascending order: a lower, dark, organic shale; a middle calcareous siltstone that is divisible into three lithic units; and an upper, dark, indurated, organic shale. The Lodgepole Formation (160 to 260 metres thick) is an argillaceous, fossiliferous limestone near the Basin …


Estimate Of Livestock Water Use In Nebraska During 1980, Eugene K. Steele Jr. Jan 1986

Estimate Of Livestock Water Use In Nebraska During 1980, Eugene K. Steele Jr.

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Nebraska Mineral Operations Review, 1985, Ray R. Burchett, Duane A. Eversoll Jan 1986

Nebraska Mineral Operations Review, 1985, Ray R. Burchett, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Reconnaissance Bathymetry Of Basins Occupied By Pleistocene Lake Lahontan, Nevada And California, Larry Benson, M. D. Mifflin Jan 1986

Reconnaissance Bathymetry Of Basins Occupied By Pleistocene Lake Lahontan, Nevada And California, Larry Benson, M. D. Mifflin

United States Geological Survey: Staff Publications

Beginning about 12,500 years B.P., Lake Lahontan began to decline (fig. 1: Black Rock Desert data from Davis [1983]; Truckee River Delta data from Born [1972]; tufa data from Benson [1981]; packrat-midden data from Thompson and others [1985]) . As water levels declined, their altitudes fell below sill altitudes (table 1); locations of these sills are shown in figure 2. Today, five surface-water bodies (Black Rock Playa, Humboldt-Carson Sink, Walker Lake, Pyramid Lake, Honey Lake) exist in four of the seven subbasins (fig. 2).

The collective surface area of the modern lakes today (1985) totals less than 1,600 km2 . …


The Effects Of Fly Ash And Flue-Gas Desulfurization Wastes On Groundwater Quality In A Reclaimed Lignite Strip Mine Disposal Site, Frank W. Beaver Jan 1986

The Effects Of Fly Ash And Flue-Gas Desulfurization Wastes On Groundwater Quality In A Reclaimed Lignite Strip Mine Disposal Site, Frank W. Beaver

Theses and Dissertations

Coal conversion wastes were generated at a lignite-coal-fired, steam-electric power station near Center, North Dakota, and were buried in unsaturated and saturated settings within the nearby stripmine, typical of settings used by the industry. The study ran for 8 years beginning in 1978. Approximately 240 piezometers were used for collecting groundwater level and groundwater chemistry data in the saturated zone. Pressure-vacuum lysimeters were installed to sample the unsaturated zone. Interstitial water was extracted from Shelby tube and auger samples at otherwise uninstrumented points.

More than 15,000 water-level recordings allowed precise definition of groundwater flow and occurrence at the study site. …


Depositional History And Diagenesis Of The Sherwood And Bluell Beds (Mississippian) Southwestern Renville County, North Dakota, Christopher F. Quinn Jan 1986

Depositional History And Diagenesis Of The Sherwood And Bluell Beds (Mississippian) Southwestern Renville County, North Dakota, Christopher F. Quinn

Theses and Dissertations

The Sherwood "bed" and the overlying Bluell "bed" are two log-defined zones at the top of the Frobisher-Alida interval. The Frobisher-Alida interval, within either the Mission Canyon carbonates or the overlying Charles evaporites, is composed of a number (up to six) of log-defined zones. On the northeast flank of the Williston Basin the zones are separated by even, lithologically homogeneous argillaceous marker beds. Basinward, these marker beds terminate into less argillaceous carbonates.

The area studied covered four townships in southwest Renville·county, North Dakota. The section studied included the K-1 marker, the Sherwood bed (with the Sherwood argillaceous marker), and the …


Paleontology And Stratigraphy Of The Niobrara Formation (Upper Cretaceous) Of Eastern North Dakota With Emphasis On The Calcareous Nannoplankton, Jeremy Reiskind Jan 1986

Paleontology And Stratigraphy Of The Niobrara Formation (Upper Cretaceous) Of Eastern North Dakota With Emphasis On The Calcareous Nannoplankton, Jeremy Reiskind

Theses and Dissertations

The Upper Cretaceous Niobrara Formation in eastern North Dakota consists of calcareous shales, chalks, and shaly chalks. The formation was studied from surface exposures, cores, and well logs. The Niobrara is 62 feet (19m) to 272 feet (83 m) and is thickest to the northeast, in a central linear area, and to the southwest. In a northern area, it was divided into a lower, calcareous shale member, and an upper, chalky member. In a.southern area, five stratigraphic units were recognized, in ascending order: a lower shaly chalk, a shale, a middle shaly chalk, a chalk, and an upper shaly chalk. …


The Stratigraphy Of The Scappoose Formation, The Astoria Formation, And The Columbia River Basalt Group In Northwestern Columbia County, Oregon, Nancy Tompkins Ketrenos Jan 1986

The Stratigraphy Of The Scappoose Formation, The Astoria Formation, And The Columbia River Basalt Group In Northwestern Columbia County, Oregon, Nancy Tompkins Ketrenos

Dissertations and Theses

The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose and Astoria Formations and determine their stratigraphic relationship to the Columbia River Basalt Group through mapping, geochemistry and petrography.


Interconnected Reproductive And Vegetative Remains Of Populus (Salicaceae) From The Middle Eocene Green River Formation, Northeastern Utah, William D. Tidwell, Steven R. Manchester, David L. Dilcher Jan 1986

Interconnected Reproductive And Vegetative Remains Of Populus (Salicaceae) From The Middle Eocene Green River Formation, Northeastern Utah, William D. Tidwell, Steven R. Manchester, David L. Dilcher

Faculty Publications

A new specimen from the Middle Eocene Evacuation Creek Member of the Green River Formation in northeastern Utah shows a twig with several leaves of Populus wilmattae Crockrell and a fruiting raceme attache. This specimen establishes for the first time the type of fruits borne by P. wilmattae and provides additional characters with which to assess its taxonomic and evolutionary status. An associated seed shows attached placental hairs like those of extant species of Populus. The Green River fossil differs from extant Populus species in having basically palmate leaf venation and in bearing its fruiting axis on a young twig. …


A Stratigraphic-Geochemical Study Of The Troutdale Formation And Sandy River Mudstone In The Portland Basin And Lower Columbia River Gorge, Rodney Duane Swanson Jan 1986

A Stratigraphic-Geochemical Study Of The Troutdale Formation And Sandy River Mudstone In The Portland Basin And Lower Columbia River Gorge, Rodney Duane Swanson

Dissertations and Theses

Hyaloclastic sediment forms an identifiable stratigraphic interval within the Troutdale Formation that can be traced from the Bridal Veil channel to the Portland basin. Hyaloclastic sediment composed chiefly vitric sands is found interbedded with muds, sandy muds and gravels penetrated by wells in northeast Portland are correlated with the upper member of the Troutdale Formation. These beds are characteristic of the informal upper member of the Troutdale Formation in the Bridal Veil channel of the ancestral Columbia River (Tolan and Beeson, 1984) and the type area of the Troutdale Formation exposed along the Sandy River (Trimble, 1963). Fluvially deposited hyaloclastic …


The Virginius Vein Ore Deposit, Northwestern San Juan Mountains, Colorado: A Study Of The Mineralogy, Structure, And Fluid Inclusions Of An Epithermal Base-Metal And Silver Vein In A Volcanic Environment, Berton Woodward Coxe Dec 1985

The Virginius Vein Ore Deposit, Northwestern San Juan Mountains, Colorado: A Study Of The Mineralogy, Structure, And Fluid Inclusions Of An Epithermal Base-Metal And Silver Vein In A Volcanic Environment, Berton Woodward Coxe

Earth and Planetary Sciences ETDs

The Virginius ore deposit, Ouray and San Miguel Counties, Colorado, yielded 14.5 million oz of silver between 1880 and 1912. The deposit consists of several quartz, base-metal, and silver mineralized fissures which is hosted by Tertiary volcanic rocks of the San Juan volcanic field and was deposited in fractures radial to the northwest margin of the Silverton caldera.

Four stages of mineralization have been recognized: (I) quartz, galena, sphalerite, chalcopyrite, and argentiferous tetrahedrite; this stage comprises a bulk of the total vein material and all of the silver; (II) rhodonite, rhodochrosite, quartz, magnetit, galena, chalcopyrite, and pyrite; this stage is …


Kinematics Of Great Basin Intraplate Extension From Earthquake, Geodetic And Geologic Information, Paul Kendall Eddington Dec 1985

Kinematics Of Great Basin Intraplate Extension From Earthquake, Geodetic And Geologic Information, Paul Kendall Eddington

All U.S. Government Documents (Utah Regional Depository)

Strain rates assessed from brittle fracture, associated with earthquakes, and total brittle-ductile deformation measured from geodetic data have been compared to paleostrain from Quaternary geology for the intraplate Great Basin of the western United States. These data provide an assessment of the kinematics and mode of lithospheric extension that the western U.S. Cordillera has experienced in the last 5-10 million years. Strain and deformation rates were determined by the seismic moment tensor method using historic seismicity and fault plane solutions. By subdividing the Great Basin into areas of homogeneous strain it was possible to examine regional variations in the strain …


Geology Newsletter- 1985, Department Of Geology Dec 1985

Geology Newsletter- 1985, Department Of Geology

Geological and Environmental Sciences News

Vol 1 No. 10

  • Dear Alumni and Friends
  • Geology Development Fund
  • Advisory Council
  • Faculty News
  • W. David Kuenzi Scholarship Fund
  • Awards and Scholarships
  • Geology and Earth Science Club


Lithofacies And Geochemistry Of Interreef Carbonates, Middle Silurian, Michigan Basin, Eric N. Porcher Dec 1985

Lithofacies And Geochemistry Of Interreef Carbonates, Middle Silurian, Michigan Basin, Eric N. Porcher

Masters Theses

The Niagara Group of the Michigan Basin is composed of reef, interreef, and basinal carbonates. The Niagara Group interreef has herein been divided into several litho facies: algal-laminated dolomicrite, bioturbated dolomicrite, intraclastic dolomicrite, wispy-laminated dolomicrite, crinoidal micrite, and nodular micrite. These interreef carbonates show a shallowing upward sequence.

The geochemistry of the Niagara Group interreef was examined in an attempt to delineate any geochemical gradients with respect to reefs. The geochemistry of the inter reef was determined by Particle Induced X-Ray Emission (PIXE) analysis. No significant geochemical gradients were found to be associated with reefs. Reasons for this may include: …


Geophysical And Hydrogeological Effects Of Astorm-Water Retention Pond On The Floridan Aquifer, Hillsborough County, Florida, Abdullah M. Alamri Dec 1985

Geophysical And Hydrogeological Effects Of Astorm-Water Retention Pond On The Floridan Aquifer, Hillsborough County, Florida, Abdullah M. Alamri

USF Tampa Graduate Theses and Dissertations

An integrated geologic, hydrologic, and geophysical investigation was conducted to determine the effect of a storm-water retention pond on the Floridan aquifer. Surface DC resistivity surveys were used to delineate the hydrostratigraphy. There are four distinct geoelectric layers: (1) Layer 1, high resistivity, 3 meters thick, fine to very fine unsaturated sand; (2) Layer 2, moderate resistivity, 1 to 2.5 meters thick, saturated sands and silts; (3) Layer 3, lower resistivity, 4 to 10 meters thick, silt and clay; (4) Layer 4, moderate resistivity, argillaceous limestone. Two fracture zones are defined by resistivity lows and marked by deep, V-shaped depressions …


The Response Of The Kentucky River Drainage Basin To A Lowering Of Base Level Control, David B. Warwick Dec 1985

The Response Of The Kentucky River Drainage Basin To A Lowering Of Base Level Control, David B. Warwick

Masters Theses

The Kentucky River has responded to a lowering of base level control by: 1) deepening the course of its channel; 2) cutting off meanders as incision proceeded; 3) developing knickpoints on tributaries; 4) widening its valley; and 5) dissecting the upland surface.

Field work involved surveying streams to obtain profiles. Twenty streams covering 125 miles of river from Carrollton to Camp Nelson, Kentucky were surveyed. Knickpoints were defined from these profiles. Data from stream profiles showed knickpoint distances decreasing with increasing distance up river. Map work involved obtaining data for hypsometric curves. Hypsometric integrals were determined from these curves. Data …


The Geology, Geochemistry, And Alteration Of Red Butte, Oregon: A Precious Metal-Bearing Paleo Hot Spring System, Carol Susan Evans Nov 1985

The Geology, Geochemistry, And Alteration Of Red Butte, Oregon: A Precious Metal-Bearing Paleo Hot Spring System, Carol Susan Evans

Dissertations and Theses

Red Butte is located 60 km south of Vale, Oregon, about 20 km west of the Oregon/Idaho border. The butte is within the Owyhee Upland physiographic province of eastern Oregon which lies at the intersection of the Western Snake River Plain, the High Lava Plains, and the Northern Basin and Range provinces.

The butte is composed of Miocene to Pliocene lacustrine and fluvial volcaniclastic sediments. The topography of the butte is controlled by silicification of the sandstones and mudstones which cap it. Silicification and hydrothermal alteration are both structurally and stratigraphically controlled. North-trending normal faults dominate the area, and show …


Geometry Of Silicic Dikes Beneath The Inyo Domes, California, Jonathan H. Fink Nov 1985

Geometry Of Silicic Dikes Beneath The Inyo Domes, California, Jonathan H. Fink

Geology Faculty Publications and Presentations

Structural geologic evidence in the vicinity of the Inyo Domes indicates that the youngest extrusive products were erupted from a silicic dike that divided into at least three segments which underwent up to 30° of clockwise rotation as they neared the surface. The geometry of ground cracks, explosion craters, and surface structures on the domes suggest that the dike may have propagated laterally from a source beneath Mammoth Mountain, with both the overall-dike and the individual segments rising as they moved northward. Structural evidence and tephrochronology also imply that the actual vents may have migrated northward along individual dike segments …