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Articles 27811 - 27840 of 29997
Full-Text Articles in Entire DC Network
Bivalve Associations Of The Cannonball Formation (Paleocene, Danian) Of North Dakota, Rosanne M. Lindholm
Bivalve Associations Of The Cannonball Formation (Paleocene, Danian) Of North Dakota, Rosanne M. Lindholm
Theses and Dissertations
The Cannonball Formation (Paleocene, Danian) is best exposed in southwest-central North Dakota. Here, two major lithotypes, mudstone and sandstone, occur. In this area, the Cannonball can be informally subdivided into four lithologic units: lower (primarily thinly-bedded sandstone and mudstone), lower-middle (sandstone), upper-middle (mudstone), and upper (sandstone). The Cannonball is also exposed in southwestern North Dakota where it occurs as two mudstone tongues (upper and lower).
During July and August, 1982, thirteen Cannonball outcrops were studied. Bivalves, along with other macrofossils, were collected quantitatively in an attempt to determine fossil species dominance. Rock samples were also collected and analyzed for textural …
Quaternary Volcanology Of The West Crater-Soda Peaks Area, Southern Washington Cascade Range, David R. Polivka
Quaternary Volcanology Of The West Crater-Soda Peaks Area, Southern Washington Cascade Range, David R. Polivka
Dissertations and Theses
The West Crater-Soda Peaks area covering about 100 km is located 35 km southeast of Mount St. Helens in southern Washington State. It is one of several Quaternary monogenetic High Cascade volcanic centers overlying the Ohaaapecosh Formation of the Western Cascade Group and interstratified glacial till.These volcanic centers are the most westerly of the range.
A Shallowing-Upward Sequence In A Pleistocene Coral Reef And Associated Facies, San Salvador, Bahamas, Brian White, Karen J. Kurkjy, H. Allen Curran
A Shallowing-Upward Sequence In A Pleistocene Coral Reef And Associated Facies, San Salvador, Bahamas, Brian White, Karen J. Kurkjy, H. Allen Curran
Geosciences: Faculty Publications
The Sangamon-age Cockburn Town fossil coral reef complex displays a vertical sequence of facies from coral reef and closely associated subtidal carbonate sands, through beach calcarenites, to eolianites. This upward change reflects a progressive lowering of sea level and the eventual emergence of the reef complex into a subaerial environment. The contact between upper beach sediments and eolianites is at +4 m providing a minimum for the sea level high stand. Essentially in situ Acropora palmata suggests a sea level of at least 5 to 6 m above present. These values are similar to Sangamon-age high stands reported from New …
Field Guide To The Cockburn Town Fossil Coral Reef, San Salvador, Bahamas, H. Allen Curran, Brian White
Field Guide To The Cockburn Town Fossil Coral Reef, San Salvador, Bahamas, H. Allen Curran, Brian White
Geosciences: Faculty Publications
James W. Teeter (ed.), 1984, Proceedings of the 2nd Symposium on the Geology of the Bahamas:San Salvador, CCFL Bahamian Field Station
Conodonts Of The Bakken Formation (Devonian And Mississippian), Williston Basin, North Dakota, Michael D. Hayes
Conodonts Of The Bakken Formation (Devonian And Mississippian), Williston Basin, North Dakota, Michael D. Hayes
Theses and Dissertations
The Bakken Formation is a thin (maximum 145 ft., 44 m), predominantly elastic unit in the subsurface of the Williston Basin in the United States and Canada. The formation consists of two, mostly non-calcareous, grayish-black to brownish-black shales separated by light to dark gray, calcareous and dolomitic siltstone and fine-grained sandstone. The carbonaceous, black shales of the Bakken produce a distinctive geophysical marker and are a major source rock for hydrocarbons in the Williston Basin.
Conodonts were selectively sampled from cores of the Bakken in North Dakota in an effort to determine the age and thermal maturity of the formation. …
Archean Metamorphism In Northwestern Ontario And Southeastern Manitoba, Kevin R. Henke
Archean Metamorphism In Northwestern Ontario And Southeastern Manitoba, Kevin R. Henke
Theses and Dissertations
Four areas are considered in this study. In Ontario, north-south traverses were made along Highway 599 between Savant Lake and Central Patricia, along the Vermilion River road (40 kilometers northeast of Sioux Lookout) and along Highway 105 between Vermilion Bay and Ear Falls (Fig. 3). The fourth area is centered at Bird River, northeast of Lac du Bonnet, Manitoba. The study areas are located in the Uchi, English River and Wabigoon Subprovinces.
The traverse along Highway 599 between Savant Lake and Central Patricia crosses the three subprovinces (Fig. 3). Pelites in the eastern Lake St. Joseph area (Uchi Sub province) …
Tertiary Alkalic Igneous Activity, Potassic Fenitization, Carbonatitic Magmatism, And Hydrothermal Activity In The Central And Southeastern Bear Lodge Mountains, Crook County, Wyoming, Gordon A. Jenner
Theses and Dissertations
The Bear Lodge Mountains are located in Crook County in north eastern Wyoming. The core of the uplift consists of alkalic igneous rocks that range from Early to Late Eocene in age. A petrologic and geochemical study of surface and subsurface samples from the southeastern and central portions of the core reveals a complex history of multiple alkalic igneous events, potassic metasomatism, carbonatitic magmatism, and hydrothermal alteration.
An early episode of alkalic igneous activity is represented by latite and trachyte porphyries, phonolite and trachyte porphyries, and natrolite-garnet syenites and malignites. Throughout much of the complex, the composition of these older …
The Ashern Formation (Middle Devonian) In The Williston Basin, North Dakota, Frederick K. Lobdell
The Ashern Formation (Middle Devonian) In The Williston Basin, North Dakota, Frederick K. Lobdell
Theses and Dissertations
The Ashern Formation (Middle Devonian) is the basal unit of the Kaskaskia Sequence in North Dakota. It unconformably overlies the Interlake Formation (Silurian) and underlies, probably paraconformably, the Winnipegosis Formation (Middle Devonian). The Ashern is present in the northwestern one-half of the state, and attains a maximum thickness of 180 feet (55 meters) The Ashern Formation may be subdivided into a lower red member and an upper gray member. The latter directly overlies the Interlake Formation where the red member is absent. Both members are argillaceous, microcrystalline dolostones containing minor quartz silt. Anhydrite, present in both members, is much more …
Paleohydraulics Of Pleistocene Drainage Development Of The Souris, Des Lacs, And Moose Mountain Spillways, Saskatchewan And North Dakota, Mark L. Lord
Theses and Dissertations
Recent recognition of the rapid draining of numerous glacial lakes, including some in the Northern Plains, has revealed 'a need for further research concerning this process. Geomorphic interpretation of the Souris, Des Lacs, and Moose Mountain Valleys, and the gravel deposits in them, has resulted in the recognition of five phases in the development of the drainageways. Textural analyses and paleohydraulic methods were applied to the sediments associated with each phase to distinguish and characterize the discharges. Four of the five phases of development involved short-lived, high velocity (>4 m/s) discharges resulting from the rapid draining of glacial lakes; …
The Geochemical Evolution Of Saline Groundwater Within A Fresh Water Aquifer South Of Oakes, North Dakota, David L. Williams
The Geochemical Evolution Of Saline Groundwater Within A Fresh Water Aquifer South Of Oakes, North Dakota, David L. Williams
Theses and Dissertations
An area of saline/brackish groundwater south of Oakes, North Dakota has been reported by the North Dakota State Water Commission. The concentrated water (over 12,000 mg/L of total dissolved solids) is in direct hydraulic connection with relatively fresh water and shows an abrupt change in concentration and water chemistry between these two end members. The saline/brackish water is beneath a shallow trough or depression which has an approximate area of 6 square miles (15.5 square kilometres). The trough is within the northern part of the Glacial Lake Dakota plain. Sediments in the lake plain, which is an unconfined aquifer, are …
Depositional Environments And History Of The Winnipeg Group (Ordovician), Williston Basin, North Dakota, Stephen C. Thompson
Depositional Environments And History Of The Winnipeg Group (Ordovician), Williston Basin, North Dakota, Stephen C. Thompson
Theses and Dissertations
The Winnipeg Group (Ordovician) in the Williston Basin, North Dakota, contains three formations. They are, in ascending order, the Black Island Formation, herein informally divided into lower and upper members, the Icebox Formation, and the Roughlock Formation. Strata of the Winnipeg Group (maximum thickness 400 ft., 122 m) represent the initial deposits of a Middle Ordovician craton-wide transgression. Throughout most of North Dakota, the Winnipeg is unconformably underlain by the Deadwood Formation (Upper Cambrian-Lower Ordovician) and conformably overlain by the Red River Formation (Upper Ordovician).
The strata of the lower member of the Black Island Formation consist of a red-bed …
Depositional Cycles And Coral Distribution, Mission Canyon And Charles Formations, Madison Group (Mississippian), Williston Basin, North Dakota, Douglas L. Waters
Depositional Cycles And Coral Distribution, Mission Canyon And Charles Formations, Madison Group (Mississippian), Williston Basin, North Dakota, Douglas L. Waters
Theses and Dissertations
The distribution of corals, other fossils, and rock types of the Madison Group in the Williston Basin were studied in 29 cores (involving over 6,200 feet of core) from the Bottineau, Tilston, Frobisher-Alida, and Ratcliffe intervals in the western half of North Dakota. Occurrence of rock types, corals, and other fossils (brachiopods, bryozoans, red algae, and gastropods) of the Mission Canyon and lower Charles Formations were plotted in three cross-sections against the informal marker-defined intervals (Tilston, Frobisher-Alida, and Ratcliffe), as identified from well logs. Distribution and abundance of corals in nine of the more extensive cores were related to interpreted …
The Effects Of Seismic Blasting On Shallow Water Wells And Aquifers In Western North Dakota, Frank W. Beaver Jr. P. E.
The Effects Of Seismic Blasting On Shallow Water Wells And Aquifers In Western North Dakota, Frank W. Beaver Jr. P. E.
Theses and Dissertations
Seismographic petroleum exploration throughout North Dakota has generated concern over the effects of blasting on groundwater supplies and wells. A preliminary investigation revealed complaints alleging declining productivity and decreased water quality in regions where coal aquifers are extensively used. Unplugged shotholes were frequently cited as a source of problems.
Experimental results indicate that changes due to blasting occur within long term physical the aquifers rather than in specific water wells. Pumping tests conducted in a sand and coal aquifer system showed no apparent physical effects when shots were detonated one quarter mile away from the pumping wells. Shots 500 feet …
Stratigraphy And Depositional Environments Of The Fox Hills Formation (Upper Cretaceous), Bowman County, North Dakota, Daniel J. Daly
Stratigraphy And Depositional Environments Of The Fox Hills Formation (Upper Cretaceous), Bowman County, North Dakota, Daniel J. Daly
Theses and Dissertations
The sedimentary structures, trace fossils, and lithology of the Upper Cretaceous Fox Hills Formation in Bowman County, North Dakota, were studied during the summer of 1979 and the spring of 1983. Twenty-three stratigraphic sections were measured and described and lithologic samples were collected for textural and mineralogical analysis, also, the major outcrops of the formation in the Dakotas and Montana were visited.
The formation in the study area was previously defined as a 27-mthick sandstone unit, containing three members--ascending, Trail City, Timber Lake, and Colgate--that was conformable with the underlying Pierre and overlying Hell Creek Formations. The Fox Hills, as …
Stratigraphy And Depositional Environments Of The Three Forks Formation (Upper Devonian), Williston Basin, North Dakota, Gayle M. Dumonceaux
Stratigraphy And Depositional Environments Of The Three Forks Formation (Upper Devonian), Williston Basin, North Dakota, Gayle M. Dumonceaux
Theses and Dissertations
The Three Forks Formation (Upper Devonian) is present in the subsurface in the western two-thirds of North Dakota and is generally conformable with the underlying Birdbear Formation and the overlying Bakken Formation.
The Three Forks attains a maximum thickness of 265 feet (81 meters) in the central basin, east and south of the Nesson Anticline, and thins to an erosional edge in eastern North Dakota. The Three Forks is composed of micrite and dolomicrite, which may be fcssiliferous and argillaceous. From the study of core samples and detailed petrographic analysis of thin sections, five lithofacies were recognized and their extent …
Heavy Minerals Of The Cretaceous Hell Creek And Paleocene Ludlow Formations Of Slope And Bowman Counties, North Dakota, Robert A. Farris
Heavy Minerals Of The Cretaceous Hell Creek And Paleocene Ludlow Formations Of Slope And Bowman Counties, North Dakota, Robert A. Farris
Theses and Dissertations
The Cretaceous Hell Creek and Paleocene Ludlow Formations of southwestern North Dakota are nonmarine sediments of alluvial origin. The heavy minerals of these formations were specifically studied to determine the source rock types and their provenance, and generally assess the diagenetic processes which affected the heavy minerals.
The heavy minerals include zircon, rutile, tourmaline, garnet, ilmenite, spinel, apatite, epidote, sphene, pyroxene, dolomite, biotite, andalusite, pyrite, monazite, and barite. Most of the heavy minerals have angular shapes, indicating one cycle of erosion and deposition.
The heavy mineral percentages of the concretions and surrounding sediments were compared within and between the Hell …
Groundwater-Lake Interactions, Wood Lake, Benson County, North Dakota, Lori J. Ferguson
Groundwater-Lake Interactions, Wood Lake, Benson County, North Dakota, Lori J. Ferguson
Theses and Dissertations
Wood Lake is a kettle lake within the McHenry end moraine (late Wisconsinan) in eastern Benson County, North Dakota. It is part of the Devils Lake interior basin, near the drainage divide between the Devils Lake basin and the Big Coulee - Sheyenne River drainage. The moraine deposits, part of the Coleharbor Group, are composed of complexly interfingering lenses of gravel, sand, silt, and clay within the till.
Water levels in piezometers around Wood Lake indicate groundwater flows from the southwest into the west side of the lake and out of the lake along the east shore, toward the northeast. …
Hydrochemical Data For The Truckee River Drainage System, California And Nevada, Larry V. Benson
Hydrochemical Data For The Truckee River Drainage System, California And Nevada, Larry V. Benson
United States Geological Survey: Staff Publications
Abstract
Surface-water samples were collected from the Truckee River drainage system during 1975, 1976, and 1981. Data resulting from chemical analyses of these samples, as well as certain other previously unpublished data, are tabulated in this report. The report contains the following hydrochemical data:
1. Chemical composition of 21 tributaries to Lake Tahoe and the Truckee River upstream from Farad, California (May and October 1971, and June 1972).
2. Chemical composition of the Truckee River at Tahoe City (January 1968-January 1975) and at Farad, California (January 1968-June 1980), and of the Little Truckee River upstream from Stampede Reservoir, California (January …
Glacial Chronology Of The Ruby Mountains–East Humboldt Range, Nevada, William J. Wayne
Glacial Chronology Of The Ruby Mountains–East Humboldt Range, Nevada, William J. Wayne
Department of Earth and Atmospheric Sciences: Faculty Publications
The Ruby Mountains-East Humboldt Range, one of the interior mountain groups of the Basin and Range Province, lies about midway between the Wasatch Mountains and the Sierra Nevada. After Blackwelder’s description in his review of glaciation in the western mountains, Sharp mapped and named the deposits of the Lamoille and Angel Lake glaciations and correlated them with early and late Wisconsin deposits of the Great Lakes area. The refinement of relative dating (RD) methods, the availability of air photos and modem topographic maps, and new road cuts have aided the restudy of these alpine glacial deposits and the basis for …
Annual Departures From Average Annual Precipitation In Nebraska, 1850-1983, Conservation Survey Division
Annual Departures From Average Annual Precipitation In Nebraska, 1850-1983, Conservation Survey Division
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Annual Departures From Average Annual Precipitation In Nebraska, 1850-1983, Conservation Survey Division
Annual Departures From Average Annual Precipitation In Nebraska, 1850-1983, Conservation Survey Division
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Nebraska Mineral Operations Review, 1983, Raymond R. Burchett, Duane A. Eversoll
Nebraska Mineral Operations Review, 1983, Raymond R. Burchett, Duane A. Eversoll
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Inventory Of Irrigation Water Use In Box Butte County, Nebraska 1981, D. R. Lawton, L. L. Leahon
Inventory Of Irrigation Water Use In Box Butte County, Nebraska 1981, D. R. Lawton, L. L. Leahon
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Igneous Dikes At Long Valley, Ca: Emplacement Mechanisms And Associated Geologic Structures, David D. Pollard, Jonathan H. Fink, Paul T. Delaney
Igneous Dikes At Long Valley, Ca: Emplacement Mechanisms And Associated Geologic Structures, David D. Pollard, Jonathan H. Fink, Paul T. Delaney
Geology Faculty Publications and Presentations
Two hypotheses for dike emplacement are: (1) magma flows into and dilates pre-existing fractures; or (2) magma flows into and dilates self-generated fractures. In the first case dikes should be parallel to an element of the rock fabric; in the second, they should be perpendicular to the least compressive stress. The two hypotheses suggest different dike intrusion and fissure eruption mechanisms and therefore different strategies for monitoring igneous events at Long Valley. We derive a method to distinguish the two mechanisms, a priori, from in-situ stress measurements and estimates of magma pressure. Estimates of relative dilation and slip across a …
Lithology And Sedimentology Of The Graydon Springs Channel, Pennsylvanian Of Southwestern Missouri, Gregory Lee Easson
Lithology And Sedimentology Of The Graydon Springs Channel, Pennsylvanian Of Southwestern Missouri, Gregory Lee Easson
Masters Theses
"The Graydon Springs Member of Southwest Missouri, here assigned to the Warner Formation of Pennsylvanian age was sampled and examined in order to document the lithology, sedimentology, source area, stratigraphic position, and overall geologic history of these channel-like bodies. The member is composed of an upper sandstone unit and a lower conglomerate unit.
Laboratory investigations of thin sections indicate that the sandstone unit is composed of well sorted, well rounded quartz and minor amounts of accessory minerals cemented with iron oxide, commonly hematite. Field observations indicate that the conglomerate unit is composed of very poorly sorted, very well rounded chert …
Relation Of Bitumen To Ore In The Magmont West Orebody, Southeast Missouri, Mark Alan Marikos
Relation Of Bitumen To Ore In The Magmont West Orebody, Southeast Missouri, Mark Alan Marikos
Masters Theses
"Bitumen in the form of oil blebs from the Magmont West orebody of the Viburnum Trend was examined and analysed in an attempt to relate hydrocarbon distribution and origin to ore genesis. Hydrogen, carbon, nitrogen, sulfur and oxygen percentages were determined by elemental analyses. Trace element composition was determined by emmission spectroscopy and the composition of the bitumen was calculated with respect to aromatic hydrocarbons, saturated hydrocarbons and NSO (nitrogen-sulfur-oxygen) components. The bitumen and kerogen from associated shale samples were evaluated by Rock-Eval pyrolysis and pyrolysis-gas chromatography.
The bitumen was calculated to be approximately 40 to 50 percent aromatic and …
Oil Producing Upper Cherokee And Lower Marmaton (Pennsylvanian) Channel Sandstones Of Jackson And Cass Counties, Missouri, Stephen Thomas Carroll
Oil Producing Upper Cherokee And Lower Marmaton (Pennsylvanian) Channel Sandstones Of Jackson And Cass Counties, Missouri, Stephen Thomas Carroll
Masters Theses
"Approximately 240 gamma ray-neutron logs were interpreted and correlated in an attempt to isolate separate channels collectively referred to as "Squirrel" sands in the upper Cherokee and lower Marmaton (Pennsylvanian) rocks of Jackson and Cass counties, Missouri. Isopach maps were prepared for two of the identifiable fluvial sandstones and a structure map was drawn on the laterally extensive Anna Shale.
The term "Squirrel" has been applied to as many as five different sandstone packages, and thus, has been the source of a great deal of confusion. In an attempt to sort out the confusion this thesis recognizes and defines three …
Estimating Particle Sizes, Concentrations, And Total Mass Of Ash In Volcanic Clouds Using Weather Radar, David M. Harris, William I. Rose
Estimating Particle Sizes, Concentrations, And Total Mass Of Ash In Volcanic Clouds Using Weather Radar, David M. Harris, William I. Rose
Department of Geological and Mining Engineering and Sciences Publications
Observations of the March 19, 1982 ash eruption of Mount St. Helens, made by the National Weather Service (NWS, Portland, Oregon) on 5-cm radar, were used to estimate the volume of the ash cloud (2000 ±500 km3), the concentration of ash (0.2–0.6 g m−3). and the total mass of ash erupted (3–10×1011 g). The position of the cloud was also tracked by radar. Particle sizes in the ash cloud were estimated from settling velocities suggested by decreases in maximum ash cloud height with time as it moved away from the volcano. The March 19, 1982 …
Geology Newsletter- 1983, Department Of Geology
Geology Newsletter- 1983, Department Of Geology
Geological and Environmental Sciences News
Vol. 1 No. 8
- Dear Alumni and Friends
- Geology Development Fund
- Faculty News
- Geology/ Earth Science Club
- 1982-1983 Awards and Scholarships
- Alumni News
- Geology Department Graduate Students
Environment Of Deposition Of The A-1 Carbonate, Salina Group, Michigan Basin, Barbara June Leonard
Environment Of Deposition Of The A-1 Carbonate, Salina Group, Michigan Basin, Barbara June Leonard
Masters Theses
The lower Salina Group of the Michigan Basin is composed of a cyclic succession of carbonate and evaporite units. The lowermost Salina unit is the A-1 unit which consists of a lower A-1 evaporite and an upper A-1 carbonate. The A-1 unit is underlain by Niagara Group carbonates. The transition from Niagaran carbonates to A-1 evaporite to A-1 carbonate has not been thoroughly understood and previous models have not satisfied some of the evidence. This paper sets forth the hypothesis that the A-1 carbonate was deposited in a non-marine lake environment rather than an isolated marine environment. Findings supporting this …