Physical Sciences and Mathematics Commons^™

The Magmatic History Of An Aubrite Parent Asteroid: Evidence From Igneous Clasts And Trace Elements, Maya Monica Wheelock

Earth and Planetary Sciences ETDs

Norton County aubrite contains numerous igneous-textured clasts that survived severe brecciation. These clasts were studied in order to obtain information about the suite of original igneous lithologies that crystallized on an aubrite parent body. The majority of igneous clasts are pyroxenites (enstatite, with minor diopside, +/- forsterite) and orthopyroxenites (enstatite, +/- forsterite). Phase relations and textural evidence are consistent with formation from a nearly pure enstatite magma body or magma ocean, at (or near) the surface of the parent body.

A new sulfide-dominated lithology was identified in Norton County. The sulfide portion is dominated by coarse-grained oldhamite (CaS) containing rounded …

Cambrian-Early Ordovician Sequence Stratigraphy And Mount Simon Sandstone Petrology-Michigan Basin, Jeffrey T. Cottingham

Masters Theses

Michigan subsurface correlation is complicated in the Cambrian-Early Ordovician section due to limited availability of rock data. Core and cuttings examination demonstrate that similar stratigraphic sequences exist between the Michigan Basin and surrounding regions. Lithofacies in Wisconsin outcrop are similar to their basinal counterparts, and are correlated on the basis of sediment types, sedimentary structures, and the sequence stratigraphic concept.

The Mount Simon Sandstone in Michigan correlates with that observed in Illinois, Wisconsin, and Iowa. Isopach data throughout the Midwest indicate a single depocenter in Northeastern Illinois. Sedimentary structures and lithology indicate a subtidal environment that may be a progradational …

Reservoir Geology Of The Dundee Limestone, West Branch Field, Michigan, Brendan Ciaran Curran

Masters Theses

West Branch field is a low-relief, NW-SE-trending anticline near the center o f the Michigan basin. Since 1934, the Dundee Limestone (Middle Devonian) has produced over 12 million barrels of oil from this field. From core studies, six depositional facies types were recognized in the Dundee. These are dominated by bioclastic carbonate sand facies deposited in normal-marine shelf settings. Although burial cements have occluded some porosity, carbonate sand facies have retained significant primary interparticle porosity and are the most important reservoir rocks. Micritic facies with restricted faunal assemblages are present at the top of the Dundee. The top 10 to …

A Hydrogeological And Hydrogeochemical Investigation Of Groundwater At A Landfill For Sludge From The Kalamazoo Wastewater Treatment Plant, Richard Howard Christensen

Masters Theses

Major cations and anions were analyzed to determine groundwater chemistry at a site used for the disposal of municipal sludge in the late 1960s and contaminated Portage Creek sedimem dredged in the late 1970s. The disposal site consists of five unlined basins constructed over 50 to 100 feet of stratified sand and gravel outwash underlain by silt and clay. Groundwater in the outwash is unconfined and flows from east to west. A groundwater divide in the center of the site produces local divergent flow to the northwest and southwest. Measurements of chemical constituents indicate that three factors influence groundwater chemistry …

Spatial And Temporal Variations Of Synthetic Organic Compounds In The Contaminant Plume Emanating From The Kl Landfill, Lynn Diane Broede

Masters Theses

Thirty-one synthetic organic compounds have been detected in samples collected from the KL Landfill contaminant plume from March, 1980 to March, 1986. Two groups of organic compounds have been delineated based on their occurrence, concentrations, and persistence throughout the 7-year monitoring period.

Changes in plume geometry and concentration have been studied relative to time, and concentration variations have been related to selected inorganic plume parameters, distance from the landfill, and precipitation. The spatial and temporal distribution of the organic compounds are attributed to biodegradation, three biotransformation sequences, physical properties of the organics and other factors. Three abbreviated anaerobic biotransformation sequences …

Hydrogeology And Hydrogeochemistry Of The Shallow Alluvial Aquifer Zone, Las Vegas Valley, Nevada, Harry Stephen Wild Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

In Las Vegas Valley, Nevada, the shallow alluvial aquifer zone is a possible source of contamination to the principal alluvial aquifers that provide 30% of the public drinking water supply for the valley. Development of the principal aquifers has lowered pressure head in the principal aquifers and created the potential for downward seepage from the shallow aquifer zone. This study was undertaken to characterize the hydrogeology and hydrogeochemistry of the shallow alluvial aquifer zone and to compare the hydrogeochemistry of the shallow and principal alluvial aquifer zones.

A 37 well shallow ground water monitoring network was established and water-level, water-quality, …

Geochemistry Of Metal Segregation In Aubrites, And The Origin Of Their Metallic Phases, Ignacio Casanova

Earth and Planetary Sciences ETDs

In this work, I have carried out a petrographic and geochemical study of the metallic particles present in aubrites with the aim of constraining ideas about their origin and evolution. The extremely low oxygen fugacities under which enstatite meteorites formed (e.g. Larimer and Buseck, 1974; Fogel et al., 1989) and their consequent unique composition make interpretations difficult due to the lack of experimental data on highly reducing systems. I have tried to overcome the paucity of experimental data by using a theoretical thermodynamic approach to study the significance of such unique compositions based on three main themes: (1) the …

Hydrology Of A Large, Closed Arid Watershed As A Basis For Paleohydrological And Paleoclimatological Studies In The Mojave River Drainage System, Southern California, Yehouda Enzel

Earth and Planetary Sciences ETDs

A physical link between anomalous, present-day atmospheric circulation patterns over the North Pa1cific Ocean, extreme storms in southern California, the largest floods of record and lake stands in the Mojave River watershed in the Mojave Desert is demonstrated by analyzing hydrologic and climatic data. This link is then used as a modem analog to interpret hydroclimatic conditions during the latest Quaternary recorded in lake deposits in the Silver Lake playa, the terminal basin of the of the Mojave River.

The Mojave River filters out small to medium floods by discharge loss through infiltration into the alluvial aquifer and allows only …

Hydrogeology And Water Budget Analysis Of Two Interdunal Ponds Nags Head Woods Ecological Preserve, Dare County, North Carolina, Richard A. Hisert

OES Theses and Dissertations

Ground-water-fed interdunal ponds in Nags Head Woods Ecological Preserve lose as much as 7600 m³ yr^-1 of water through evaporation. This withdrawal of groundwater is sufficient to significantly alter flow patterns through the surficial aquifer on Bodie Island, N.C. Statistical analyses of evaporation estimates derived by various methods indicate a weak correlation, (r²=0.4-0.5) between pan evaporation data from Aurora, N.C. and pond evaporation at Nags Head Woods calculated by water budget analyses.

Results of stratigraphic and pedologic analyses in and around the ponds indicate that the ponds formed after development of multiple generations of dunes. This …

Hydrogeology And Hydrogeochemistry Of The Tekonsha Moraine And Adjacent Interlobate Deposits In Charleston Township, Kalamazoo County, Michigan, Victor V. Melbardis

Masters Theses

Hydrogeochemical analyses and hydrogeologic interpretations provide the basis for an understanding of local ground-water flow, in a 12 square mile study area, transected by the Tekonsha Moraine and bound by glaciofluvial deposits. Glacial tills separate an upper and lower aquifer system throughout most of the area.

Degraded and tritiated ground water is present in the lower aquifer system. A negative correlation (-0.62) between tritium concentrations and depth is statistically significant (.04). In this local system, hydrochemical trends are characterized by decreases in sulfate percentages and increases in bicarbonate in the direction of ground-water flow. Statistical evaluation of the hydrochemical data …

Potential Petroleum Reservoir Rocks Of North-Central Oregon, Alfred J. Riddle

Loma Linda University Electronic Theses, Dissertations & Projects

Petroleum explorationists have commonly assumed, based on the presence of volcanic and/or volcaniclastic rock, that regions such as northcentral Oregon do not hold potential as petroleum basins. The typical argument has been that volcanic flows have no effective porosity or permeability and poorly sorted volcaniclastic sediments contain a high percentage of mineralogically unstable grains which are too easily and rapidly altered into clays and zeolites for any significant or effective porosity to be retained.

The objective of this study was to determine if potential petroleum reservoir rocks do exist in north-central Oregon. Through field and laboratory study and by comparing …

The Hydrogeology And Leachate Generation Of An Alum Sludge Lagoon Chesapeake Virginia, Charles M. Darling

OES Theses and Dissertations

In 1986 the City of Chesapeake, Virginia began to dig shallow ponds ("lagoons") to contain alum sludge, a waste generated by the City from the process of treating potable water. Borings at the disposal site reveal that the near-surface geologic units include a thin mud-rich facies which overlies a thick sandy facies, both of which are in the Lynnhaven Member of the Tabb Formation. At 7 meters depth, a clay-rich facies of the Yorktown Formation (Morgarts Beach Member?) underlies the sandy water table aquifer. Water levels from twenty observation wells and two monitoring wells installed into the water table aquifer …

Distribution Of Sand Within Selected Littoral Cells Of The Pacific Northwest, Don Joseph Pettit

Dissertations and Theses

Beach sand acts as a buffer to wave energy, protecting the shoreline from erosion. Estimates of the quantity and distribution of beach sand in littoral cells of the PNW are critical to the understanding and prediction of shoreline erosion or accretion. This study was initiated in order to: 1) document the distribution of sand in littoral cells of the Pacific Northwest; 2) determine the factors which have brought about these present distributions; and 3) address the relationship of beach sand distribution to shoreline stability.

Metal Mobilization From A Near-Shore Lake Sediment Under Simulated Acidic Groundwater Inputs, Raveendra V. Ika

OES Theses and Dissertations

Simulation of acidic groundwater passing through lake sediments was conducted under controlled conditions in a laboratory. Three sediment cores collected intact from the near-shore region of an acidic lake were subjected to simulated groundwater inputs of initially identical chemistry for a seven day period. Following this period water being used in the simulation for two of the sediment cores was acidified by hydrochloric acid (HC1) addition to examine the ability of these sediments to neutralize acidic groundwater with varying H⁺ concentration.

Simulated acidic water passing through the sediment cores mobilized significant amounts of metals. The sediment acted as a …

Simulation Of Bromide Transport In A Layered Aquifer Using Two-Dimensional And Three-Dimensional Computer Models, Kathleen Michelle Hewitt

Masters Theses

Simulation of a two-well tracer test at a site near Mobile, Alabama was performed and compared with the experimental breakthrough curve. The models used to simulate the test results were the three-dimensional USGS code HST3D and the two-dimensional USGS code MOC. The results of the three-dimensional model were also compared with the results of the two-dimensional model.

The three-dimensional model HST3D predicted the measured breakthrough curve accurately with the exception of early arrival times of the tracer in the withdrawal well. The two-dimensional model MOC did not accurately predict the bromide concentration in the withdrawal well during the two-well test. …

Geology Of The Butler Basin, Grant And Wheeler Counties, Central Oregon, Martin R. Aguirre

Loma Linda University Electronic Theses, Dissertations & Projects

The Butler Basin lies along the John Day River in Central Oregon, astraddle the boundary of Wheeler and Grant counties. Strata exposed in this geomorphic basin, formed by an erosionally breached anticline, range in age from Permo-Triassic to Neogene. The basement rocks of the basin are poorly exposed but lithologically similar to the Permo-Triassic Blue Mountains island-arc rocks which crop out to the south and southeast of the basin in the John Day Inlier. Overlying the basement rocks are Early Cretaceous conglomerates with lenses of sandstone and siltstone informally named the "Goose Rock Conglomerate." Pebble and cobble lithologies present in …

Geology And Economic Potential Of The Muddy Ranch Inlier, North-Central Oregon, Mustafa Kamal

Loma Linda University Electronic Theses, Dissertations & Projects

There has been confusion for many years regarding the lithology and age of the rocks exposed in the Muddy Ranch Inlier in north-central Oregon. Taylor (1960) referred to these rocks as metasediments and informally named them the "Muddy Ranch phyllite". My studies indicate the inlier consists of weakly metamorphosed siltstone, mudstone, and less abundant sandstone.

Due to the absence of fossil evidence, it was not possible to determine the age of these rocks. However, from the stratigraphic setting and correlation with similar rocks exposed along structural trend to both the northeast and southwest, rocks of the Muddy Ranch Inlier may …

Paleoenvironmental Analysis Of A Late-Holocene Subfossil Coleopteran Fauna From Starks, Maine, Heather A. Hall

Senior Scholar Papers

The Sandy River in central Maine Is flanked along much of its length by low terraces. Approximately 100 kg of sediment from one terrace in Starks, Somerset County, Maine was wet-sieved in the field. Over 1100 subfossil Coleoptera were recovered representing 53 individual species of a total of 99 taxa. Wood associated with the fauna is 2000 +/-80 14C Yr in age (1-16,038). The fauna is dominated by species characteristic of habitats apparent in modern central Maine. The subfossil assemblage is indicative of a wide vartety of environments including open ground (e.g., Harpalus pensylvanicus), dense forest (e.g., pterostichus honestus), aquatic …

The Sedimentology And Stratigraphy Of The Chilhowee Group (Uppermost Proterozoic To Lower Cambrian) Of Eastern Tennessee And Western North Carolina: The Evolution Of The Laurentian - Iapetos Margin, James Daniel Walker

Doctoral Dissertations

The Blue Ridge and Piedmont provinces of the southern Appalachians possess Upper Proterozoic and Lower Paleozoic age sedimentary, metasedimentary, volcanic, and metavolcanic rock thought to represent sedimentation and igneous activity related to the formation of the Iapetos (Proto-Atlantic) ocean. These sequences of strata can be related to the development of the Laurentian - Iapetos margin as seen in the Southern Appalachians. "Rift" phase sequences of the western Blue Ridge, include the Late Proterozoic age Mount Rogers, Catoctin, Grandfather Mountain formations, and the Ocoee Supergroup, which have been interpreted by other workers as representing volcanism and sedimentation in regionally discontinuous, fault-bounded …

Laramide Deformation In Precambrian Granitic Rocks, Northeastern Wind River Range, Wyoming, Mark A. Dubois

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fractures and faults in the Jakey's Fork area, northeastern Wind River Range, Wyoming, caused by brittle Laramide deformation in the Precambrian granitic basement have been studied in detail at airphoto, outcrop, and thin-section scales. The study area is bounded on the south by the approximately east-west and vertical Jakey's Fork Fault and on the east by the approximately northwest-southeast and vertical Ross Lakes Fault. Both were active during Laramide deformation. Four distinct structural domains, defined by fracture pat terns and proximity to the two major faults nave emerged in this study. The areas are: 1) Along Ross Lakes Fault granite …

Geology, Volcanology, And Petrology Of Cerro Bravo, A Young, Dactic, Stratovolcano In West-Central Colombia, David Tondl Lescinsky

LSU Historical Dissertations and Theses

The northernmost active Andean volcano, Cerro Bravo is a small, young, and very explosive stratovolcano. Cerro Bravo has produced voluminous tephra deposits, that are found> 30 km away, as well as, pumice flow deposits, block and ash flow deposits, and high-aspect lava flows, which are found proximally to the volcano. There have been eight episodes of activity during the past 6250±110 years (Herd, 1982), with the most recent <200 years ago and the present being a period of quiescence with no visible activity or thermal manifestations. Stratigraphic relationships suggest the occurrence of an initial explosive phase and a concluding effusive phase of activity during individual episodes. The products of volcanic activity at Cerro Bravo are a chemically and mineralogically monotonous suite of medium-K dacite and high-silica andesite (59.2- 67.5% SiO₂ pumices and lavas. The dominant phenocrysts present are plagioclase and hornblende (oxyhomblende in lavas) with lesser quantities of orthopyroxene, titanomagnetite, and rare augite and biotite also present. Petrology and eruption dynamics …

Stromatolites Of The Lower Cambrian Deep Spring Formation; Mount Dunfee, Esmeralda County, Nevada, Lynn Oliver

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Middle Member of the Lower Cambrian Deep Spring Formation at Mount Dunfee, Nevada contains a diverse assemblage of stromatolites that formed on a tide- and storm-dominated, siliciclastic-influenced, carbonate shelf. The stromatolites formed in a shallow subtidal environment within and near active oolite shoals under strongly focused currents. The stromatolites occur in four different lithofacies: (1) bioherms of digitate stromatolites, (2) bioherms and biostromes of inclined stromatolites, (3) isolated forms of massive and hemispheroidal stromatolites, and (4) a biostrome of cryptomicrobial boundstones. The first three lithofacies are interpreted as microbial reefs. They had topographic relief, formed in active agitated waters, …

Strain And Volume Loss In A Second Order Buckle Fold, Central Appalachian Valley And Ridge, U.S.A., Michelle J. Markley

Honors Papers

Large scale thrusts and imbricates overlain by folded sedimentary strata characterize structure in the Valley and Ridge Province of the Central Appalachians. The Cambrian Waynesboro Formation is a decollement zone that detached an imbricated Cambro-Ordovician sequence from an unfaulted Pre-Cambrian basement. The Ordovician Martinsburg Shale is a second zone of major detachment that de-coupled the blind thrust system in the Cambro-Ordovician carbonates from the overlying orogenic wedge. Thus, the Central Valley and Ridge deformed during the late Paleozoic Alleghenian orogeny as a three tiered system consisting of the undeformed basement, the imbricated stiff layer, and the primarily folded cover layer. …

The Geology Of Taconic Thrust Sheets And Surrounding Carbonates Of The West Central Vermont Marble Belt, North Of Rutland, Vermont, Kay Bierbrauer

Geology Theses and Dissertations

The carbonates of the Vermont Valley and the overlying rocks of the Taconic sequence have been generally believed to lie on the east limb of a major unfaulted syncline (Middlebury Synclinorium). In this view a westward dipping, north-south trending basal Taconic overthrust must be exposed somewhere along the eastern margin of the Taconic Range.
In contrast, this study based on detailed mapping at the north end of the Taconic Allochthon suggests that a folded overthrust surface is only locally seen in fensters; more commonly the basal obduction surface of the Taconic Allochthon has been truncated by later cross-cutting thrust faults. …

Geochemistry Of Garnet Xenocrysts And Garnet-Bearing Xenoliths In Ordovician Bentonites, Barbara Bock

Geology Theses and Dissertations

Within outcrops of the black Utica shales south of the Mohawk Valley narrow re-entrants parallel with stratification are visible, often accompanied -by a marked orange-staining of the underlying strata. These rentrant features indicate the presence of bentonites weathered back faster then the enclosing shales. These bentonites are presumably magmatic ashes related to extensive volcanism when an island arc collided with the North American continent in the late Ordovician about 450 million years ago (Taconic orogeny).
Bentonites are good stratigraphic markers because of the short time-interval they represent and the large area they cover. Therefore they are commonly used as correlation …

Petrology And Major Element Geochemistry Of Basaltic Glasses From The Blanco Trough, Northeast Pacific, Glenn A. Gaetani

Geology Theses and Dissertations

The original electron microprobe analyses of suite of basaltic glasses recovered in 1968 by W.G. Melson and co-workers from the Blanco Trough have extremely unusual characteristics. Their compositions plot in a region of the normative Ol-Di-Pl-SiO2 tetrahedron which suggests that they represent liquids in equilibrium with an upper mantle assemblage of olivine + orthopyroxene at 10-15 kb. Given the present state of controversy surrounding the composition and depth of origin of primary MORB, natural examples of such liquids would be very important. The major element variations observed in the suite imply that the dominant phases are olivine and an iron-aluminum …

Application Of A Trace Element Fractionation Model To Cumulate Gabbroic Xenoliths Of Mauna Kea, Hawaii, Ulrike Eberle

Geology Theses and Dissertations

A trace element fractionation model originally designed to relate plutonic rocks containing a trapped glass component to a complementary volcanic rock suite was applied to olivine and opaque-oxide gabbroic xenoliths from the summit cone of Mauna Kea, Hawaii.
The mathematical model which is based on the Rayleigh Fractionation Law was extended to include the various phases present in these two groups of gabbros and was generalized to treat multiple trace elements, in this case four. These results were incorporated in a new FORTRAN program using the interval-bisection method to greatly improve the convergence time in the numerical solutions.
Calculated results …

Geology And Structure Of The Rocks Associated With The Basal (Madstone) Thrust Of The Josephine Ophiolite In Southwestern Oregon: Evidence For A Metamorphic Sole, Kristin A. Grady

Geology Theses and Dissertations

Many ophiolites have amphibolite at their base which contains a sharp inverted grade of metamorphism. These metamorphic soles are thought to have formed during the detachment and emplacement of the ophiolite. In addition to the sharp inverted grade of metamorphism, other characteristics of metamorphic soles include 1). a highly strained peridotite unit of the hanging wall which has concordant structures with underlying amphibolite and 2). an underlying melange sequence and continental rocks.
The Madstone thrust displaces the Josephine peridotite (Josephine ophiolite-162 Ma) onto amphibolites and underlying deformed gabbros of the Chetco Intrusive Complex. The rocks associated with the Madstone thrust …

Origin, Sedimentary Geochemistry, And Correlation Of Middle And Late Ordovician K-Bentonites: Constraints From Melt Inclusions And Zircon Morphology, Carsten Schirnick

Geology Theses and Dissertations

The present study of Paleozoic K-bentonites demonstrates that the geochemistry of melt inclusions and the morphology of zircons can be studied by inexpensive and simple-to-use methods, which rely on phenocrysts. Constraints are obtained that lead to (a) the origin of these altered volcanic ashes, (b) the geochemistry of ash-to-K-bentonite-alteration, and (c) the reliable correlation of extensively altered volcanic ashes (i.e. K-bentonites).
Silicic melt inclusions (i.e. non-devitrified) have been found in quartz and zircon phenocrysts contained within Ordovician and Devonian K-bentonites from New York State, the Upper Mississippi Valley, and Pennsylvania. Origin, source, and tectonic setting of the volcanism that produced …

Gravity Maps, Models And Analysis Of The Greater Portland Area, Oregon, Paul Thomas Beeson

Dissertations and Theses

Growing concern over earthquakes in the Pacific Northwest has prompted the mapping and location of near surface faults in the Portland area, Oregon. Visible evidence of faults is poor, requiring the use of geophysical methods to assist in mapping and defining structures in the basin. Gravity maps and models may help in addressing this problem.