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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.


A Possible Mechanism For The Diurnal Oscillations Of Tropical Cyclones, Jay S. Hobgood Jan 1986

A Possible Mechanism For The Diurnal Oscillations Of Tropical Cyclones, Jay S. Hobgood

Department of Earth and Atmospheric Sciences: Faculty Publications

A possible mechanism for the diurnal oscillations of tropical cyclones is presented. In the conceptual model developed to explain these features, the diurnal cycle of net radiation at the cloud tops is identified as the primary cause of the oscillations. Radiative cooling of the cloud tops at night steepens the lapse rate and increases convection. This generates a slight intensification in the storm. The reverse occurs during the daytime as the cloud tops absorb solar radiation. This process may be augmented by differential cooling of cloudy and clear areas.

This conceptual model is tested through the use of a numerical …


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.


Age Of The Earliest African Anthropoids, John G. Fleagle, Thomas M. Bown, John D. Obradovich, Elwyn L. Simons Jan 1986

Age Of The Earliest African Anthropoids, John G. Fleagle, Thomas M. Bown, John D. Obradovich, Elwyn L. Simons

United States Geological Survey: Staff Publications

The earliest fossil record of African anthropoid prunates (monkeys and apes) comes from the Jebel Qatrani Formation in the Fayum depression of Egypt. Reevaluation of both geologic and faunal evidence indicates that this formation was deposited in the early part of the Oligocene Epoch, more than 31 million years ago, earlier than previous estimates. The great antiquity of the fossil higher prunates from Egypt accords well with their primitive morphology compared with later Old World higher prunates. Thus, the anthropoid primates and hystricomorph rodents from Fayum are also considerably older than the earliest higher primates and rodents from South America.


Discovery Of Two Additional Prosimian Primate Families (Omomyidae, Lorisidae) In The African Oligocene, Elwyn L. Simons, Thomas M. Bown, D. Tab Rasmussen Jan 1986

Discovery Of Two Additional Prosimian Primate Families (Omomyidae, Lorisidae) In The African Oligocene, Elwyn L. Simons, Thomas M. Bown, D. Tab Rasmussen

United States Geological Survey: Staff Publications

Three new specimens reported here are referable to the Omomyidae and Lorisidae, and represent only the second and third prosimian primates found in the Oligocene rocks of the Fayum, Egypt. The Fayum omomyid extends the range of the Omomyidae into Africa, while the Fayum lorisid is the oldest record of the Lorisidae world-wide. Afrotarsius established ?Tarsiidae as a third prosimian family present in Oligocene rocks of the Fayum region of Egypt (Simons & Bown, 1985). These new occurrences significantly reorient paleogeographic study of primate origins. In a fauna famed for the presence of about a thousand specimens of early Anthropoidea-viz. …


Thalassiosira Praeoestrupii- A New Diatom Species For Recognizing The Miocene/Pliocene Epoch Boundary In Coastal California, Michael P. Dumont, Jack G. Baldauf, John A. Barron Jan 1986

Thalassiosira Praeoestrupii- A New Diatom Species For Recognizing The Miocene/Pliocene Epoch Boundary In Coastal California, Michael P. Dumont, Jack G. Baldauf, John A. Barron

United States Geological Survey: Staff Publications

A new diatom species, Thalassiosira praeoestrupii Dumont, Baldauf and Barron, is described. The first occurrence of T. praeoestrupii in coastal California diatom-bearing outcrops occurs between the last occurrence of Rouxia californica at 6.0 Ma, and the first occurrence of Thalassiosira oestrupii at 5.1 Ma. The latter two species have customarily been used to identify the Miocene/Pliocene boundary. Paleomagnetic studies at Santa Cruz, California, demonstrate that the first occurrence of T. praeoestrupii coincides with the top of magnetic polarity Chron 5, which closely approximates the Miocene/Pliocene Epoch boundary.


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. …


Kurzbericht Der Ersten Deutschen Speläologischen Himalaya-Expedition, Herbert Daniel Gebauer Jan 1986

Kurzbericht Der Ersten Deutschen Speläologischen Himalaya-Expedition, Herbert Daniel Gebauer

International Journal of Speleology

The first German speleological expedition to the Himalaya went to the terrace sediments of Pokhara, Nepal. New discoveries could be made in the longest cave of the Himalaya (Patalae Chhango or Harpan-River-Cave) and other caves were surveyed for the first time. Due to the observations the classification of conglomerate-caves as pseudokarst-appearances has to be questioned.


Origination Of Stone Forests In China, Lin Hua Song Jan 1986

Origination Of Stone Forests In China, Lin Hua Song

International Journal of Speleology

The stone forests are widely distributed in the tropical and subtropical climatic areas. The stone forests may be divided into hilltop stone forest, hill slope stone forest and the stone forest in the depressions or valleys. The conditions for stone forest development should be (1) thick and pure limestone, (2) gentle dipping of limestone formation, generally less than 15°, (3) a lot of vertical joint and fissure networks, (4) the soil covering on the limestone surface inhomogeneous, thick in the fissures and thin on the rock top surface, and (5) the soil should be wet and contain rich organic materials …


The Speleogenetic Role Of Air Flow Caused By Convection. 1st Contribution, Arrigo A. Cigna, Paolo Forti Jan 1986

The Speleogenetic Role Of Air Flow Caused By Convection. 1st Contribution, Arrigo A. Cigna, Paolo Forti

International Journal of Speleology

In the past some authors described the speleogenetic role of convection in phreatic conditions. Similar effects exist also in the air-filled part of vadose passages of caves as a consequence of an air circulation due to a relevant temperature gradient; the effects can be enhanced by the presence of some acids as, e.g., H2S, H2SO4, etc. In this paper the conditions matching convection and condensation which produce typical forms, very similar to those found under phreatic conditions, are discussed both for limestone and gypsum caves.


Use Of Cave-Maps For Tectonic Surveys, Franz Jaskolla, Peter Volk Jan 1986

Use Of Cave-Maps For Tectonic Surveys, Franz Jaskolla, Peter Volk

International Journal of Speleology

Results of the author’s investigations show the useful application of cave-map-data for tectonic assessment. Considering speleological features, cave genesis, and structural differences, it is possible to select of the cave map’s pattern various jointing and stress systems. By 7 selected cave maps, representing areas of different tectonic history (W-Germany, Austria and Switzerland) it will be demonstrated that three types of kinematic joint-systems can be identified (fundamental, orthogonal- fold- and shear-system). Therefore, tectonic models are expected to become more valuable. It must be stated that future tectonic investigations in karst-areas should include the additional use of cave maps.


Evidence For Karstic Mechanisms Involved In The Evolution Of Moroccan Hamadas, Vittorio Castellani, Walter Dragoni Jan 1986

Evidence For Karstic Mechanisms Involved In The Evolution Of Moroccan Hamadas, Vittorio Castellani, Walter Dragoni

International Journal of Speleology

Underground tubular karst features, observed in an arid envinronment of southern Morocco, are described. On the basis of various evidences, it is suggested that such features were originated mainly by condensation water. A computation of the time necessary for their formation supports this hypothesis.


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.


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 …


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. …


Biogeochemical Processes In Sagebrush Ecosystems: Interactions With Terrain, United States, National Aeronautics And Space Administration Dec 1985

Biogeochemical Processes In Sagebrush Ecosystems: Interactions With Terrain, United States, National Aeronautics And Space Administration

Plants

Field data collection to support analysis of TM data was accomplished from June 22 to August 28th. Color infrared aerial photography acquired by a U2 on June 12, 1985 was used to locate and identify several vegetation communities. Forty sites where the USFS has collected long term ground cover were located in the field, delineated on aerial photos and ground photos of current conditions taken.


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


The Use Of Electrical Resistivity To Delineate A Brine Contamination Plume In The Walker Oilfield, Kent County, Michigan, Kent E. Meisel Dec 1985

The Use Of Electrical Resistivity To Delineate A Brine Contamination Plume In The Walker Oilfield, Kent County, Michigan, Kent E. Meisel

Masters Theses

Contamination of groundwater with oil field brines was reported in the Walker Oil Field, Michigan. An electrical resistivity survey utilizing the Vertical Electrical Sounding method was conducted to test the method as an exploratory tool for delineating brine contamination in glacial deposits. The method was successful in defining the subsurface geology and delineating a shallow, confined aquifer, but the presence of extensive, conductive clays effectively masked the presence of brine contamination. The method was shown to be an effective exploratory tool for shallow investigations.


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 …


Use Of Nitrification Inhibitors On Wheat, Lloyd W. Murdock Dec 1985

Use Of Nitrification Inhibitors On Wheat, Lloyd W. Murdock

Soil Science News and Views

Nitrogen is one of the most important inputs 1in wheat production, but sometimes one of the most difficult to manage. Sources of nitrogen commonly used in Kentucky have most or all of their nitrogen in the ammonium (NH+4) form or forms readily converted to NH+4 (anhydrous ammonia 100%, urea 100%, N-solutions 75%, ammonium nitrate 50%), The ammonium form of nitrogen is used by the plant and retained in the soil with little chance 2f loss, In soils with temperatures above 50°F the ammonium is converted to the nitrate (NO3) form of nitrogen. Nitrate …


Reply To Comment On "Subduction Of The Caribbean Plate And Basement Uplifts In The Overriding South American Plate", James N. Kellogg, William E. Bonini Dec 1985

Reply To Comment On "Subduction Of The Caribbean Plate And Basement Uplifts In The Overriding South American Plate", James N. Kellogg, William E. Bonini

Faculty Publications

No abstract provided.


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: …


Thiram And Methiocarb As Deer Mouse Repellents And Agents For Conditioned Aversion, Bobbi A. Holm Dec 1985

Thiram And Methiocarb As Deer Mouse Repellents And Agents For Conditioned Aversion, Bobbi A. Holm

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


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 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 …