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A Hydrogeologic Study Of The Local Groundwater Flow System At Osmond, Ne, Jonathan Alix Jan 1987

A Hydrogeologic Study Of The Local Groundwater Flow System At Osmond, Ne, Jonathan Alix

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource Notes-Fall/Winter 1986-87 Jan 1987

Resource Notes-Fall/Winter 1986-87

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Significant Rises And Declines In Nebraska Groundwater Levels (From Pre-Development As Of Fall 1985)/Registered Irrigation Wells In Nebraska (As Of January 1, 1986), Conservation Survey Division, U.S. Geological Survey Jan 1987

Significant Rises And Declines In Nebraska Groundwater Levels (From Pre-Development As Of Fall 1985)/Registered Irrigation Wells In Nebraska (As Of January 1, 1986), Conservation Survey Division, U.S. Geological Survey

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Isostatic Compensation And Conduit Structures Of Western Pacific Seamounts: Results Of Three-Dimensional Gravity Modeling, James N. Kellogg, Bruce S. Wedgeworth, Jeffrey T. Freymueller Jan 1987

Isostatic Compensation And Conduit Structures Of Western Pacific Seamounts: Results Of Three-Dimensional Gravity Modeling, James N. Kellogg, Bruce S. Wedgeworth, Jeffrey T. Freymueller

Faculty Publications

Detailed three-dimensional polygonal prism models of two large western Pacific seamounts show that the 135 mgal difference in the observed sea surface gravity over the two can be best explained by similar mean densities (2.6 gjcm3) and crustal thickening under one seamount (Airy isostatic compensation). Observed calculated residuals are further reduced by including dense (2.9 gjcm3) vertical feeder pipes or volcanic conduits in the models. Dense conduits or fracture zones 5 to 17 km in diameter are located under many, if not all, craters on volcanic islands and seamounts. Results from the detailed seamount studies can be generalized using exact …


A 3-D Gravity Tectonic Study Of Ita Mai Tai Guyot: An Uncompensated Seamount In The East Mariana Basin, Bruce S. Wedgeworth, James N. Kellogg Jan 1987

A 3-D Gravity Tectonic Study Of Ita Mai Tai Guyot: An Uncompensated Seamount In The East Mariana Basin, Bruce S. Wedgeworth, James N. Kellogg

Faculty Publications

Ita Mai Tai is a large, locally uncompensated seamount on the eastern edge of the East Mariana Basin. A large positive gravity anomaly of 254 mgal characterizes the summit and a low of -69 mgal, the surrounding moat. Using polygonal prisms to approximate the bathymetry, the observed gravity was inverted to calculate an average density of 2.59 g/ems for the seamount. Observed-calculated gravity residuals are reduced by including the flanking sedimentary basins and a dense volcanic conduit. The drill sites from DSDP Legs 20 and 89 describe a volcanic edifice formed in the Aptian!Albian on Jmassic/Cretaceous crust. The volcanism is …


Metamorphism In The Wabigoon Subprovince In The Vicinity Of Vermilion Bay And Sioux Lookout, Ontario, Christine K. Roob Jan 1987

Metamorphism In The Wabigoon Subprovince In The Vicinity Of Vermilion Bay And Sioux Lookout, Ontario, Christine K. Roob

Theses and Dissertations

The Wabigoon-English River subprovince boundary has been proposed by various workers to be either a fault, an unconformity, an intrusive contact or a gradational boundary. North of the Wabigoon Fault, in the Vermilion Bay-Dryden area, migmatization and partial melting of meta sediments have produced a variety of metatexitic and diatexitic migmatites. Because migmatites are not encountered in the Wabigoon subprovince proper and the area north of the Wabigoon fault is so different from the rest of the subprovince, it is thought that the area may constitute the southernmost part of the English River sub province.

The Wabigoon Subprovince is a …


The Providence Island Formation In The Northern Appalachian Region - A Lower-Lower Middle Ordovician Analogue To Recent Arid-Semiarid Tidal-Flat Carbonates Of The Persian Gulf Trucial Coast, Mauricio Roma Hernandez Jan 1987

The Providence Island Formation In The Northern Appalachian Region - A Lower-Lower Middle Ordovician Analogue To Recent Arid-Semiarid Tidal-Flat Carbonates Of The Persian Gulf Trucial Coast, Mauricio Roma Hernandez

Geology Theses and Dissertations

The Providence Island Formation of Early-early Middle Ordovician age occurs in the Champlain Valley and adjacent areas in eastern New York, western Vermont, and southern Quebec. The unit forms part of a carbonate shelf sequence which occupied the eastern margin of the North American continent from Newfoundland to Alabama, and its lithology is representative of the dolostone lithofacies that characterizes the uppermost Beekmantown Group in this region.
This is the first study documenting depositional environments, diagenesis, and stratigraphic correlations of the Providence Island Formation. This formation consists, in decreasing abundance, of dolostones, limestones, shales, and dedolostones. The dominantly fine grain …


Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will Jan 1987

Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will

Geology Theses and Dissertations

This work has involved an experimental approach and a study of naturally produced slickensides.
The experiments, carried out on a pyrophyllitic rock, have been performed in order to define some extrinsic parameters that control surface and microstructural features. Normal stress, speed (i.e. strain rate), and amount of slip and total displacement were related to measureable surface features, such as length, and spacing between the developing ridges and grooves. Special attention was paid to a newly recognized type of slickenside lineation (Means, 1986). This lineation produced experimentally cannot be explained in terms of the traditional asperity ploughing or dissolution/precipitation models. It …


Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer Jan 1987

Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer

Geology Theses and Dissertations

The Kula volcanics are a small Pleistocene to Recent volcanic field located on the north shoulder of the Gediz graben, approximately 120 km east of Izmir. The field consists of a mixture of flows, small cones and pyroclastic deposits erupted during three periods of volcanic activity beginning about one million years ago. The volcanics range in composition from basanites to trachybasalts, commonly porphyritic with abundant clinopyroxene, olivine and amphibole phenocrysts. The lavas also host a wide variety of megacrysts, crustal xenoliths and hydrous mantle-derived nodules. These volcanics unconformably overlie Neogene lacustrine sedimentary rocks and the metamorphic basement rocks of the …


Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak Jan 1987

Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak

Geology Theses and Dissertations

The Taconic Allochthon is an elongate belt of Cambro-Ordovician, argillaceous sediments with lesser occurrences of calcareous and siliceous lithologies. These lithologically distinctive strata lie tectonically juxtaposed over a coeval medial-Ordovician carbonate shelf sequence. This geometry resulted from an arc-continent collision in which a westward-migrating arc (Ammonoosuc Volcanics) collided with an eastern North America passive margin and the accumulated accretionary prism of the forearc region was thrust onto the passive continental margin.
The present thesis examined the structural sequence at the north end of the Allochthon and the continuity of this sequence into the adjacent Parautochthonous Shelf strata. Structurally, the study …


Identification Of Endmembers For Magma Mixing In Little Sitkin Volcano, Alaska, Douglas A. Wolf Jan 1987

Identification Of Endmembers For Magma Mixing In Little Sitkin Volcano, Alaska, Douglas A. Wolf

Geology Theses and Dissertations

Little Sitkin island is an Aleutian calc-alkalic volcanic center that has erupted a suite of lavas ranging from andesite through rhyodacite. Whole-rock chemistry of these lavas indicates contrasting evolutionary processes; major-oxide silica variation diagrams exhibit linear trends that are suggestive of magma-mixing while trace-element trends are largely controlled by accessory-phase fractionation.
Plagioclase, the dominant phenocryst phase in all lavas, commonly occurs in two distinct populations with markedly different compositions and textures. Both normal and reverse zonation is noted in the plagioclase and clinopyroxene of several samples. In addition, clinopyroxene is found as rims on orthopyroxene grains and as cores with …


Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich Jan 1987

Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich

Geology Theses and Dissertations

Granitic pegmatites associated with the Grenville orogeny intrude a mid-Proterozoic, upper amphibolite to near granulite facies terrane in the southeastern Adirondack Mountains of New York State. The inferred anatectic, fluid-saturated, and minimum melt characteristics of the pegmatites suggest that they can be used as analogs of the "granite" or "haplogranite" system, and as indicators of crustal temperature, pressure, and fluid conditions during a late stage of the Grenville orogeny. Bulk chemical compositions of seven simple, undeformed pegmatites in the southeastern Adirondacks indicate that they are generally depleted in silica and sodium, and enriched in potassium, relative to experimental data on …


Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr Jan 1987

Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr

Geology Theses and Dissertations

The Lems Ridge olistostrome (LRO), located within the western Jurassic belt of the Klamath Mountains geologic province, is a melange unit showing a distinct block-in-matrix fabric. The conformable relationship to both an igneous basement and the overlying flysch of the Late Jurassic Galice Formation points to a sedimentary origin. The lack of pervasive deformation and the internal stratification also support a predominantly olistostromal origin of the LRO. The matrix of the LRO consists of pebbly mudstone which interfingers with tuffaceous greenstone and tuff-breccias. Subordinate beds of chert, argillite, and sandstone are also present. The matrix contains abundant ophiolitic clasts, fragments …


Geology Of The Northern Baie Verte Peninsula, Newfoundland, Canada, Pamela J. Stella Jan 1987

Geology Of The Northern Baie Verte Peninsula, Newfoundland, Canada, Pamela J. Stella

Geology Theses and Dissertations

On the eastern portion of the Burlington Peninsula of northwest central Newfoundland, Canada, there are two different age groups of volcanic and volcaniclastic rocks. There have been arguments in the past as to whether or not these two groups are actually only one group (Cape St. John Group) but with progressive intensity of deformation and metamorphism from south to north. Other workers have divided the rocks into two distinct groups, the Grand Cove Group and the Cape St. John Group based on their differences in deformation style and metamorphic grade. This study ignored previous divisions of the rocks into one …


Stable Isotope Compositions Of Fossil Mollusks From Southern California: Evidence For A Cool Last Interglacial Ocean, Daniel R. Muhs, T. Kurtis Kyser Jan 1987

Stable Isotope Compositions Of Fossil Mollusks From Southern California: Evidence For A Cool Last Interglacial Ocean, Daniel R. Muhs, T. Kurtis Kyser

United States Geological Survey: Staff Publications

Stable isotope compositions have been determined for modem mullusks and fossil mollusks collected from uplied marine terraces at three l d t i e s in southern California. By using a paleocliatic model that decouples the temperature and ice-volume signals in ocean water, ocean-water temperatures off southern California are estimated to have been -3.8 °C at ~85 ka, -3.0 °C at ~107 ka, and -2.2 °C at ~125 ka relative to present temperature. These results indicate rather cool conditions during the peak of the last interglacial stage at 125 ka and conflict with results from terrace faunal studies that suggest …


A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury Jan 1987

A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury

Masters Theses

"The pre-Pennsylvanian structure at Crooked Creek consists of a complex, vertically faulted ring of Cambrian and Ordovician sediments with a central uplifted core. The center of the structure is strongly deformed and contains shatter cones, brecciation, and other signs of extreme shock.

A magnetic low over the center of the structure suggests that igneous material was not involved in the formation of the structure, and this is corroborated by core analysis. Gravity data indicates several small gravity lows, possibly associated with areas of brecciation, circling the flanks of the structure. As in the magnetic data, there is no indication that …


Analysis Of Coal Samples From The Southwestern District, Kentucky (Clay, Jackson, Knox, Laurel, Lee, Mccreary, Owsley, Whitley, And Parts Of Bell, Clinton, Estill, Madison, Pulaski, Rockcastle, And Wayne Counties), James C. Currens, Linda Jean Bragg, James C. Hower Jan 1987

Analysis Of Coal Samples From The Southwestern District, Kentucky (Clay, Jackson, Knox, Laurel, Lee, Mccreary, Owsley, Whitley, And Parts Of Bell, Clinton, Estill, Madison, Pulaski, Rockcastle, And Wayne Counties), James C. Currens, Linda Jean Bragg, James C. Hower

Information Circular--KGS

Chemical and petrographic data ore presented for 119 samples of cool collected in the Southwestern District, eastern Kentucky. The data include sample-site locations, sampling conditions, stratigraphic position, megoscopic description of the cool, air-drying loss, proximate and ultimate analyses, Btu content, forms of sulfur, initial deformation temperature, softening temperature, fluid temperature, free-swelling index, concentration of major- and minor-oxides and trace elements, and petrographic analyses.


Analysis Of Coal Samples From The Upper Cumberland District, Kentucky (Parts Of Bell, Harlan, Letcher, And Whitley Counties), James C. Currens, Linda Jean Bragg, James C. Hower Jan 1987

Analysis Of Coal Samples From The Upper Cumberland District, Kentucky (Parts Of Bell, Harlan, Letcher, And Whitley Counties), James C. Currens, Linda Jean Bragg, James C. Hower

Information Circular--KGS

Chemical and petrographic data ore presented for 57 samples of cool collected in the Upper Cumberland District, eastern Kentucky. These data include sample-site locations, sampling conditions, stratigraphic position, megoscopic description of the cool, air-drying loss, proximate and ultimate analyses, Btu content, forms of sulfur, initial deformation temperature, softening temperature, fluid temperature, free-swelling index, concentration of major- and minor-oxides and trace elements, and petrographic analyses.


Analysis Of Coal Samples From The Big Sandy District, Kentucky (Floyd, Johnson, Martin, And Pike Counties), James C. Currens, Linda Jean Bragg, James C. Hower Jan 1987

Analysis Of Coal Samples From The Big Sandy District, Kentucky (Floyd, Johnson, Martin, And Pike Counties), James C. Currens, Linda Jean Bragg, James C. Hower

Information Circular--KGS

Chemical and petrographic data ore presented for 146 samples of cool collected in the Big Sandy District, eastern Kentucky. The data include sample-site locations, sampling conditions, stratigraphic position, megoscopic description of the cool, air-drying loss, proximate and ultimate analyses, Btu content, forms of sulfur, initial deformation temperature, softening temperature, fluid temperature, free-swelling index, concentration of major- and minor-oxides and trace elements, and petrographic analyses.


Lake Weir Eutrophication Study: Final Report For Phases I And Ii, Thomas Crisman, Anne E. Keller, Jeffrey K. Jones, Henry Meier, John R. Beaver Jan 1987

Lake Weir Eutrophication Study: Final Report For Phases I And Ii, Thomas Crisman, Anne E. Keller, Jeffrey K. Jones, Henry Meier, John R. Beaver

School of Geosciences Faculty and Staff Publications

No abstract provided.


Nebraska Mineral Operations Review, 1986, Raymond R. Burchett, Duane A. Eversoll Jan 1987

Nebraska Mineral Operations Review, 1986, Raymond R. Burchett, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Depositional Environments And Diagenesis, Winnipegosis Formation (Middle Devonian), Williston Basin, North Dakota, Nancy A. Perrin Jan 1987

Depositional Environments And Diagenesis, Winnipegosis Formation (Middle Devonian), Williston Basin, North Dakota, Nancy A. Perrin

Theses and Dissertations

In the Williston Basin, the Winnipegosis Formation is the major carbonate unit of the initial transgressive-regressive pulse of the Kaskaskia sequence. Twenty-two lithofacies were identified by well-log, core, and thin-section studies of Winnipegosis rocks; these belong to seven environments of deposition which include deep basin, deep shelf, shallow shelf, reef, lagoon, tidal flat, and evaporite basin. The deposition of the Winnipegosis and Prairie Formations were inter-related and occurred during six episodes. Following a brief hiatus separating the underlying Ashern Formation from the Winnipegosis, a clear, quiet, shallow-marine environment became established in the North Dakota portion of the Elk Point Basin. …


Field Peas In The Wheatbelt, R J. French Jan 1987

Field Peas In The Wheatbelt, R J. French

Journal of the Department of Agriculture, Western Australia, Series 4

Plantings of lupins in the Western Australian wheatbelt increased rapidly in the late 1970s and early 980s as improved varieties became available and farmers realised the benefits to be gained from growing grain legumes. Grain legumes are useful not simply as alternative cash crops. They provide 'fixed' atmospheric nitrogewn to following cereal crops and act as a cleaning crop to break cereal disease cycles. They are also valuable sheep feed.

In 1975, throughout the wheatbelt, the Department of Agriculture began a comparison of several alternative legumes. The crops included field peas, faba beans, chickpeas, lentills and various vetches. Field peas …


Gypsum Use In The Wheatbelt, M R. Howell Jan 1987

Gypsum Use In The Wheatbelt, M R. Howell

Journal of the Department of Agriculture, Western Australia, Series 4

One of the limitations to crop productivity in the wheatbelt is the poor structure of heavy textured soils. Many years of clearing and cultivation have caused the loss of soil organic matter and breakdown of soil aggregates - particles of sand, silt and clay - in the surface layers. This has led to the development of unstable soils with poor physical properties.

Although loss of soil structure is a serious problem, it can be reversed by altering the tillage practices that caused the problem. This improvement in soil structure and return to productivity can be a slow process. However gypsum …


Glacial Deposits, Vol. 15, 1986-1987, Department Of Geography-Geology Jan 1987

Glacial Deposits, Vol. 15, 1986-1987, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Evaluation Of The Interaction Between Seepage From A Municipal Waste Stabilization Lagoon, Mcville, North Dakota, And A Shallow Unconfined Aquifer, Paul R. Bulger Jan 1987

Evaluation Of The Interaction Between Seepage From A Municipal Waste Stabilization Lagoon, Mcville, North Dakota, And A Shallow Unconfined Aquifer, Paul R. Bulger

Theses and Dissertations

The McVille, North Dakota, Municipal Waste Stabilization Lagoon is situated above the McVille Aquifer, an unconfined glaciofluvial aquifer capable of significant water yields. The site contains a 3-D network of 29 monitoring wells. Standing waste-water is maintained in the clay-lined, primary-operating cell. Operating practices at the site entail periodic discharges of waste-water from the lined cell to an unlined cell, a procedure which results in rapid infiltration.

The shape and extent of the groundwater contaminant plume caused by the waste-stabilization process is best delineated by the distribution of chloride. Background wells contain less than 10 mg/L chloride. The area up …


Diagenesis And Porosity Development Of The Mission Canyon And Charles Formations (Mississippian), Treetop And Whiskey Joe Fields, North Dakota, Rebecca L. Durall Jan 1987

Diagenesis And Porosity Development Of The Mission Canyon And Charles Formations (Mississippian), Treetop And Whiskey Joe Fields, North Dakota, Rebecca L. Durall

Theses and Dissertations

Rocks of the upper Mission Canyon and lower Charles Formations (Mississippian) in central Billings County, North Dakota consist of interbedded limestones, dolostones, and anhydrites which were deposited in a shallow epeiric sea. This study was limited to the upper Mission Canyon and lower Charles Formations of Treetop and Whiskey Joe fields, located along the Billings anticline in central Billings County, North Dakota. Close examination of ap~roximately 260 metres (850 feet) of upper Mission Canyon and lower Charles Formations core in the study area resulted in the separation of rocks into six lithotypes: 1) echinoderm wackestone, 2) dolomudstone, 3) neomorphic wackestone, …


A Mineralogical Study Of The Harmon Lignite Bed, Bullion Creek Formation (Paleocene), Bowman County, North Dakota, Christopher J. Zygarlicke Jan 1987

A Mineralogical Study Of The Harmon Lignite Bed, Bullion Creek Formation (Paleocene), Bowman County, North Dakota, Christopher J. Zygarlicke

Theses and Dissertations

Study of the Harmon lignite bed at the Gascoyne Mine in Bowman County, North Dakota showed that most of the minerals in the coal lithobodies were detrital in origin and that variable ash deposition during combustion may be caused by variations in types and quantities of mineral phases.

The Harmon bed is part of the Bullion Creek Formation (Paleocene). Objectives of this study included: to develop scanning electron microscope/microprobe techniques for the study of minerals in coal; to determine the origins of the mineral phases; to postulate a depositional environment for the Harmon lignite; and to ascertain whether variable ash …


Stratigraphic Model Of The Southern Portion Of The Jim Bridger Coal Field, Sweetwater County, Wyoming, Paul S. Maywood Jan 1987

Stratigraphic Model Of The Southern Portion Of The Jim Bridger Coal Field, Sweetwater County, Wyoming, Paul S. Maywood

Dissertations and Theses

Uppermost Lance and lowermost Fort Union Formation sediments are found in outcrop in the southern portion of the Jim Bridger coal field, located on the northeast flank of the Rock Springs Uplift in Sweetwater County, Wyoming. Twenty-nine surface sections and 581 subsurface (borehole) sections were evaluated and used to construct a stratigraphic model.

Stratigraphic correlations with economically mineable coal seams in the Fort Union Formation north and south of the study area combined with definition of questionable local formational boundary locations are significant objectives in this investigation.


Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii Jan 1987

Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii

Dissertations and Theses

A computer technique for interpreting geophysical logs of drill-holes in quantitative lithologic terms has been developed and tested on the deposits of the late Eocene Coaledo Formation, a well-studied fluvio-deltaic complex in southwestern Oregon. The technique involves the use of induced and natural gamma logs for separation of coal and claystone from coarse-grained detrital rocks and the use of the ratio of resistivity and natural gamma responses (defined here as the "grain size index") to divide the coarse elastic rocks into a series of textural classes corresponding to the Wentworth-Odden particle size scale.