Earth Sciences Commons^™

The Hydrogeology Of Nags Head Woods, Dare County, North Carolina, Janet Salyer Emry

OES Theses and Dissertations

Nags Head Woods, a coastal maritime forest located on a barrier island in eastern North Carolina, stabilizes a back-barrier dune system bordering a tidal marsh. The purpose of this study is to provide basic information about the groundwater geology in Nags Head Woods and to predict the effects upon water levels due to municipal pumping of Fresh Pond, a large lake near the center of the island.

Clean, fine-to-medium sands dominate the top of the surficial (water table) aquifer, underlain by silty fine-to-coarse sands at -4 m elevation. A silty clay bed of very low permeability is present at -12 …

Fracture Detection In A Volcanic Oil Reservoir Using Discriminant Analysis Of Well Log Data, Joseph William Cross

OES Theses and Dissertations

A new method of detecting fractures using well logs is presented. The technique uses discriminant analysis to distinguish fractured from unfractured reservoir rock and was developed for the volcanic pay zone of Jatibarang oilfield, West Java, Indonesia.

The a priori information required to derive the discriminant function was provided by 22 wells known to penetrate intervals of either fractured or unfractured volcanics. The samples consisted of these 22 intervals digitized in one-meter increments (1256 meters total thickness). The discriminating variables were the petrophysical measurements made by 10 different types of well logs.

Discriminant analysis correctly classified 94.2% of the total …

Benthic Foraminifera And Paleoenvironments Of The Arcola Limestone Member Mooreville Formation (Campanian) In Eastern Mississippi And Western Alabama, Julia K. Palmer

OES Theses and Dissertations

Eighty-one species of benthic foraminifera have been recovered from chalky marls of the upper Mooreville Formation including the Arcola Limestone Member, and the basal Demopolis Formation located in five sections in east-central Mississippi and west-central Alabama. These species have been described and seventy-nine illustrated. Analysis of the environmental or depth preferences of abundant species together with planktonic percentages and benthic species diversity, indicates that the chalky marls were deposited in a broad shallow shelf sea (subtidal conditions less than 100m) greatly influenced by open ocean conditions. The benthic assemblage is composed of a mixture of typically neritic and bathyal species …

Lineament Analysis In The Richmond Triassic Basin Area Virginia: A Kinematic Model, Richard D. Lutz

OES Theses and Dissertations

A lineament study from various sources (color-infrared U-2 photos, rectified drainage maps, and aeromagnetic maps) was conducted to develop a conceptual kinematic model for the Richmond Triassic basin area in Virginia. The lineaments were digitized and subjected to a computerized correlation package that compared the statistically significant peaks within 8 km² grid cells. Spatially filtered significant 10° contoured trends exhibited a high correlation with mapped structures, outcrop patterns, diabase dikes, and aeromagnetic alignments, suggesting that they represent the surface expressions of the boundaries of subsurface structural domains. Structurally important lineament zones include NE-trending lineaments which segment the basin, NNW-trending …

Relationship Of Stream Drainage And Airphoto-Derived Lineaments To Basement Structures In The North Central Virginia Coastal Plain, William F. Mullen

OES Theses and Dissertations

A lineament study was conducted in the north central coastal plain of Virginia using five different data sources; color infrared photo images, rectified stream segments, bouguer gravity anomaly maps, aeromagnetic anomaly maps, and residual magnetic anomaly maps to determine the potential of aerial photographic analysis in the delineation of basement structural features beneath the sedimentary cover of the Virginia Coastal Plain.

Statistical analysis of 1602 airphoto lineaments and 2337 rectified stream segments produced 15 airphoto lineaments and 18 rectified stream segment lineaments in the north central Coastal Plain Province of Virginia. Azimuthal coincidence of these 33 lineaments determined that there …

Deep Flow Variability In Central Drake Passage, John M. Klinck, Eileen E. Hofmann

CCPO Publications

A rotary empirical orthogonal function analysis of the currents measured in central Drake Passage during DRAKE 79 shows that the deep (2500 m) flow has the same spatial and temporal structure as the flow at 500 m, suggesting that current variability in this region penetrates to the bottom. However, comparison of the time amplitude of the corresponding modes indicates that the variability of the 2500 m flow resulting from north to south shifts in the location of the Polar Front lags that at 500 m by one to three days. This implies that the Polar Front slopes to the east …

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

Biological Sciences Faculty Publications

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

The Physics Of The Antarctic Circumpolar Current, Worth D. Nowlin, John M. Klinck

CCPO Publications

A region of transition of surface water characteristics from subantarctic to Antarctic and an associated eastward flowing Antarctic Circumpolar Current (ACC) have long been recognized to exist as a band around Antarctica. In this review we summarize the most important observational and theoretical findings of the past decade regarding the ACC, identify gaps in our knowledge, and recommend studies to address these. The nature of the meridional zonation of the ACC is only now being revealed. The ACC seems to exist as multiple narrow jets imbedded in, or associated with, density fronts (the Subantarctic and Polar fronts) which appear to …

On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi

OES Faculty Publications

Summary. The statistical capability of the m_b :M_s, discriminant for the discrimination of earthquake and explosion populations is examined by application of discriminant functions to a group of 83 explosions and 72 earthquakes in Eurasia. Equations are derived for the probability that an event is an earthquake or an explosion. The positive sign of DIS in the decision index equation,

DIS, = 34.3383 - 11.9569 mb_i, + 7.1 161 M_si,

indicates that the event i is an earthquake. Its negative sign indicates that event i is an explosion. The probability of …

Leachate Monitoring In Naturally Saline Groundwater Chesapeake Landfill Chesapeake Virginia, T. Britt Mcmillan

OES Theses and Dissertations

Groundwater chemistry around the Chesapeake municipal landfill was monitored over a one year period. Ten sample sites as well as two surface water sites were used to monitor water quality. Two wells, one at 3 m and the other at 10 m were located at each site. Surface water samples were taken from the Elizabeth River, north of the landfill, and a tidal channel, west of the landfill. Seven groundwater sites were downgradient of the landfill and three sites were upgradient (control sites).

The landfill overlies a tidal marsh, approximately 100 m south of the intracoastal waterway (Elizabeth River). Dredge …

Lineament Analysis And Tectonic Interpretation For The Central Tharsis Region, Mars, Robert C. Anderson

OES Theses and Dissertations

Lineament studies conducted for the Central Tharsis Region of Mars (JOON and JOOS latitude; 450w to 157.50W longitude) indicate two major events controlled the formation of the Tharsis Dome: 1) a pre-Tharsis fracture system consisting of North-West (3150) trending fractures; and 2) a Tharsian fracture system containing North-South (355°) and East-West (275°) trending fractures. The North-West (3150) trending fractures represent a crustal weakness zone which controlled the early formation of the Tharsis Dome. Analytical studies suggest four centers of uplift: 1) 6°N, 124°W; 2) 0.5°N, 114°W; 3) 5°S, 105°W; and 4) 7°S, 104°W. Each of these uplifting centers is associated …

Conodont Biostratigraphy Of The Cambrian-Ordovician Boundary Interval In The Northern Shenandoah Valley Of Virginia, U.S.A., Randall C. Orndorff

OES Theses and Dissertations

Conodonts collected from two measured sections in the northern Shenandoah Valley of Virginia indicate that locally the Cambrian-Ordovician boundary is within the upper part of the Conococheague Formation and that the Conococheague-Stonehenge formational contact as defined in this study, is diachronous in relation to the boundary. Using the generally accepted definition of the CambrianOrdovician boundary as at the base of the trilobite Missisguoia Zone or within the conodont Hirsutodontus hirsutus Subzone of the Cordylodus proavus Zone, it is found here that the boundary is 230 ft (70 m) below the formational contact at the Narrow Passage Creek section. Several North …

Depositional Model For The Auriferous Gravels In The Payan Mining District Department Of Narino, Columbia, South America, Jim R. Garrett

OES Theses and Dissertations

Unlike placer deposits in arid and semi-arid environments where gold concentration is closely tied to the position of the bedrock, Payan placer deposits have no association with bedrock. Gold concentration values show highest gold concentrations occur at the contact of a coarse sand unit and its underlying gravel unit. Comparisons of the size and shape distributions of gold grain populations with their associated black sand populations indicate the gold and black sand were not deposited in hydraulic equilibrium. The mean size of each gold population is consistently coarser than the mean size of its associated black sand population despite the …

Depositional Environments Of Late Precambrian Sediments From Liberia, Sierra Leone, And Senegal, West Africa, Alfred W. Magee Iii

OES Theses and Dissertations

Field and hand sample descriptions were supplemented with petrographic and textural analyses derived from thin sections, and scanning electron microscopy (SEM) to determine environments of deposition for the late Precambrian Gibi Mountain Formation, Liberia, Tabe

Formation, Sierra Leone, and the basal Mali Group, Senegal, West Africa.

The Gibi Mountain Formation consists of a glaciomarine tillite, marine laminites with dropgrains, and shallow water arkoses. A shale facies remains unresolved in origin.

The Tabe Formation is composed of three members: Tibai, Dodo, and Taban. The Tibai Member contains a glaciomarine tillite deposited in a shallow shelf marine environment, marine laminites, and shallow …

Fluvial Depositional Processes Of A Tropical River, Colombia, South America, Michael L. Babuin

OES Theses and Dissertations

Fluvial depositional processes along the Rio Magui in south-western Columbia are primarily controlled by localized uplift downstream of the mouth of the river, sediment sources that produce both coarse-and-fine-grained load, and numerous over-bank flows caused by torrential rainfall.

A Geophysical Model Of The Gravity-Magnetic High, Virginia Coastal Plan, Gordon Everett Davison

OES Theses and Dissertations

The coastal plain province of Virginia is characterized by a coincidental gravity and magnetic high separating Appalachian-trend geophysical signatures to the west from non-Appalachian signatures to the east. Two cross-trend gravity and magnetic profiles, one on the Northern Neck of Virginia and one along Interstate Highway 64, were used to interpret the anomalous high. The profile models suggests that the anomaly is characterized by high-density, variably magnetic, east-dipping (60°) crustal blocks. Further information from well-logs indicate that the anomaly is due to meta-mafic rocks of oceanic origin, flanked by low-density, lower susceptibility, granitic units. This suggests that the anomalous gravity-magnetic …

Foraminiferal Paleoenvironments Of The Eastover Formation (Upper Miocene Virginia), Joann H. Goshorn

OES Theses and Dissertations

Sixty-two taxa representing 29 genera from 39 foraminiferal sample pairs have been documented and analyzed in a paleoenvironmental study of the Eastover Formation in southeastern Virginia. The Eastover Formation consists of a lower Claremont Manor Member, a silt fine-grained sand and an upper Cobham Bay Member, a shelly fine grained sand. Planktonic specimens were rare and indicated a late Miocene to early Pliocene age for the Eastover Formation. Benthics were used to interpret paleoenvironments by comparison with data from the distribution of Recent foraminifera, species diversity, planktonic to benthic ratios, and sediment analyses. The foraminifera indicate that the Eastover Formation …

Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai

OES Faculty Publications

Summary. From 1977 March 21 to 1981 July 28, about 15 earthquakes with M_s ≥6.0 and many earthquakes with M_s≥4.5 have occurred in Iran. The upsurge of seismic activity started following the Khorqu earthquake of 1977 March 21, M,=7.0, south-east of the Fars folded series of Zagros. This shock had a thrust focal mechanism solution indicating the general northward movement of the Arabian plate with respect to the Iranian landmass. It was followed by six major damaging earthquakes in eastern Iran. The earthquakes are associated with extensive faulting which surrounds the Lut plate. (1) The Zarand earthquake …

Microbial Manganese Reduction By Enrichment Cultures From Coastal Marine Sediments, David J. Burdige, Kenneth H. Nealson

OES Faculty Publications

Manganese reduction was catalyzed by enrichment cultures of anaerobic bacteria obtained from coastal marine sediments. In the absence of oxygen, these enrichment cultures reduced manganates when grown on either lactate, succinate, or acetate in both sulfate-free and sulfate-containing artificial seawaters. Sodium azide as well as oxygen completely inhibited microbial manganese reduction by these enrichment cultures, whereas molybdate had no effect on them. The addition of nitrate to the medium slightly decreased the rate of Mn²⁺ production by these enrichment cultures. These findings are consistent with the hypothesis that the manganese-reducing organisms in these enrichment cultures use manganates as terminal …

The Use Of Ilmenite Element Composition For The Determination Of Provenance, Yu W. Tsang

OES Theses and Dissertations

Fifty three samples were taken from three major rivers and their tributaries in Virginia: the James, Roanoke. and Potomac-Shenandoah Rivers. Samples were obtained from the Valley and Ridge. Blue Ridge and Piedmont provinces. The possible source rock types for these samples were determined by comparison of tributary ilmenite composition with drainage basin rock types. Ilmenite element concentration varied with different rock types. Ti was usually high for the ilmenite derived from non-mafic igneous rocks. Mg and Cr were high for the ilmenite from mafic igneous rocks. Zn was low for metamorphic ilmenite. The ilmenite from sedimentary rocks tended to have …

Sedimentologic And Stratigraphic Significance Of Boulder Layers In The Outer Coastal Plain Of Southeastern Virginia, Robert C. Mcdaniel

OES Theses and Dissertations

In southeastern Virginia one to two discontinuous boulder layers occur at the base of the Pleistocene Norfolk Formation. The sediments, heavy minerals and microfossils within the boulder layers in addition to boulder lithologies, dimensions and orientations were studied to determine the origin of these layers. These data indicate the boulder layers were separated into two similar yet distinct layers.

The ancestral James River with sea-level 100 meters lower than today probably had the capacity to entrain 70-80 percent of the clasts in the boulder layers, but probably not the capacity to entrain the larger cobbles and boulders in the boulder …

Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane

OES Theses and Dissertations

Biostratigraphic analysis of Late Miocene and Pliocene strata along the Piankatank River in eastern Virginia exposes a juxtaposition of the Eastover and Yorktown Formations. This structure is situated on a NE trending alignment of geological, geomorphic, and geophysical features which run from southern Virginia to northern Delaware. Tectonic jointing in isolated sandstone bodies and fracture controlled drainage patterns provide further evidence of post-middle Pliocene tectonism in the region. The lateral spacing of this structure from the Stafford and Brandywine fault zones and other linear features on the Coastal Plain strongly implies that a structural similarity exists between the Piankatank structure …

Stratigraphy And Textural Analyses Of A Beach Ridge Complex, Cape Henry, Virginia, Daniel Leland Oyler

OES Theses and Dissertations

Eight lithological units, documented from the analyses of 26 boreholes, comprise five laterally extensive horizons in the subsurface of Cape Henry, Virginia. Interpretations of the environments of deposition for those units are based upon textural and compositional features, fossils, thickness and distribution of strata, and previous reports about late Tertiary and Quaternary deposits in nearby areas. The incised, Pliocene Chowan River Formation (Unit H) underlies Pleistocene Units F and G which are concentrated in a buried river valley beneath Cape Henry. Estuarine Units D and E resulted from a marine transgression of the study area during the early Holocene. The …

Fourier Series Analysis Of The Relationship Of Morphologic Variations And Bathymetry In Recent Bolivina (Foraminiferida) From The Northwestern Gulf Of Mexico, Anthony Cavedo Gary

OES Theses and Dissertations

Automated video digitization and closed-form Fourier series analysis were used to investigate the applicability of benthic foraminiferal test morphology for paleo-bathymetric/paleoenvironmental reconstructions. Sample relationships and harmonics with the greatest power for discriminating between samples were determined using canonical discriminant analysis. Samples were eleven short cores obtained from the northwestern Gulf of Mexico. Three species of Bolivina were analyzed, B. albatrossi, B. lowmani, and B. subspinescens.

Results show populations of Bolivina albatrossi from the upper bathyal and upper-middle bathyal zones to have more triangular tests and lobulate chambers than lower-middle and lower bathyal zone populations. Specimens of Bolivina subspinescens …

A High-Resolution Bathymetry Map For The Marguerite Bay And Adjacent West Antarctic Peninsula Shelf For The Southern Ocean Globec Program, S. T. Bolmer, R. C. Beardsley, C. Pudsey, P. Morris, P. Wiebe, Eileen E. Hofmann, J. Anderson, A. Maldonado

OES Faculty Publications

One objective of the U.S. Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) program is to gain a better understanding of the sea floor bathymetry in the program study area. Much of Marguerite Bay and the adjacent shelf west of the Antarctic Peninsula were poorly charted when the SO GLOBEC program started in 2000. Before the first SO GLOBEC cruise, an improved local area version (ETOPO8.2A) was created from the Smith and Sandwell (1997) topo_8.2.img 2-minute digital gridded bathymetry for the study area. The first SO GLOBEC mooring cruise on the R/V Lawrence M. Gould (March 2001) showed that the …

The Aquatic Geochemistry Of The Particle-Reactive Radionuclides Po-210, Pb-210, And Be-7, James Forrest Todd

OES Theses and Dissertations

Integrated monthly wet-only and bulk precipitation samples for Be-7 and Pb-210 analysis were collected from November 1982 through October 1983 at two sites in lower Chesapeake Bay. Atmospheric deposition fluxes for Be-7 in wet-only and bulk precipitation averaged 0.013 and 0.014 pCi/cm²/d, respectively, and for Pb-210 averaged 0.36 and 0.40 pCi/cm²/yr, respectively, suggesting that dry deposition makes only a minor contribution to the total fluxes.

A seasonal trend was observed in the depositional flux of Be-7, with a pronounced maximum in the Spring. Approximately 40 percent of the annual Be-7 deposition occurred between February and April, …

A Method For Determining Creosote Contamination Of Sediment From The Elizabeth River, Norfolk, Va, Elizabeth G. Merrill

OES Theses and Dissertations

Hydrocarbon input sources to the Elizabeth River were investigated. Carbonized coal products (creosote, coal tar, and roof tar), petroleum products (Kuwait Crude Oil, No. 2 Fuel Oil, and a fuel oil spill sample) and soot (woodstove and diesel engine) have unique hydrocarbon distributions. Elizabeth River sediment hydrocarbon distributions indicate that they are contaminated with both carbonized coal and petroleum products. Using a simple two member mixing model, greater than 65 percent of Elizabeth River sediments' resolved aromatic compounds were determined to originate from carbonized coal products. These aromatic hydrocarbons include the EPA priority pollutant polynuclear aromatic hydrocarbons which are known …

The Marine Biogeochemistry Of Selenium: A Re-Evaluation, Gregory A. Cutter, Kenneth W. Bruland

OES Faculty Publications

Vertical and horizontal profiles from the North and South Pacific Oceans demonstrate the existence of three species of dissolved selenium: selenite, selenate, and organic selenide (operationally defined). In surface waters, organic selenide makes up about 80% of the total dissolved selenium, selenite concentrations are uniformly low, and selenate concentrations rise with increased vertical mixing. The organic selenide maximum (thought to consist of seleno-amino acids in peptides) coincides with the maxima of primary productivity, pigments, bioluminescence, and dissolved free amino acids. Deep ocean waters are enriched in selenite and selenate, while organic selenide is nondetectable. In suboxic waters of the tropical …

Trace-Elements In Ilmenite - A Way To Discriminate Provenance Or Age In Coastal Sands, Dennis A. Darby

OES Faculty Publications

Trace elements and Ti percentage in ilmenite grains magnetically separated from modern and late Pleistocene coastal sands of southeastern Virginia and northwestern North Carolina were used to distinguish different deposits. Multivariate analysis of ilmenite composition (Ti, Mn, Mg, Cr, V, Ni, and Cu) from coastal deposits and potential source rivers enabled the identification of dominant source rivers. Using the trace element content of one mineral instead of heavy-mineral suites eliminated most of the hydraulic sorting, selective weathering, and intrastratal solution problems that often obscure heavy-mineral provenance determinations. Most ilmenite grains lacked exsolution or twinning, which are common to ilmenite; however, …

The Effect Of Polynuclear Aromatic Hydrocarbons On The Fecundity Of Acartia Tonsa (Calanoid Copepoda), Juanita Y. Grabarczyk

OES Theses and Dissertations

The concentrations of polynuclear aromatic hydrocarbons (PNAHs) were determined for several stations in the Elizabeth River. Thirteen PNAHs of the sixteen EPA priority pollutant PNAHs were present in the particulate fraction. The concentrations ranged from 10.0 ng/1 to 1000 ng/1. Ten of the sixteen EPA priority pollutant PNAH were present in the dissolved phase. Concentrations ranged from 2.0 ng/1 to 100 ng/1.

The environmental PNAHs concentrations were used to determine test concentrations. Bioassays were conducted to determine the effects of indigenous concentrations of seven predominant PNAHs (0.01 mg/1 to 2.4 mg/1 concentrations) on the fecundity of Acartia tonsa (calanoid Copepoda). …