Earth Sciences Commons^™

Arsenic Heterogeneity In Aquifer Sediments From West Bengal, India, Emily Eastridge

Theses and Dissertations--Earth and Environmental Sciences

Multiple studies in the Bengal basin have shown that elevated As in groundwater coincides with reduced, relatively dark sediments of Himalayan provenance. In West Bengal state (India), As concentrations > 10 μg/L tend to occur east of the River Bhagirathi-Hoogly, the main distributary of the Ganges. Associations among sediment chemistry and mineralogy for four cores from either side of the Bhagirathi-Hoogly (cores 1 and 2 to the east, 3 and 4 to the west) in Murshidabad district were investigated. Ten sediment samples were collected from each boring at various depths to a maximum of 38 to 43 m. Sediment chemistry was …

Locating Hot Spots Of Fecal Pollution In An Urban Watershed Of Central Kentucky Using Bacteroides 16s Rrna Markers, Tricia L. Coakley

Theses and Dissertations--Earth and Environmental Sciences

The field of molecular fecal source tracking in the water environment has developed rapidly since the first PCR assays for general and host-­‐specific Bacteroides 16s rRNA markers were published. Numerous host-­‐specific molecular markers and PCR assays have been developed, adding greater specificity, sensitivity and quantitative methods to the array of options. The public demand for readying methods for transfer to the commercial lab, so that they may be used to generate data for public utilities, citizen action groups and regulatory agencies, has fueled the development of an entire new research community. These methods, however plentiful, have not found community agreement …

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …

Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin, Christopher D. Henry, Allen J. Mcgrew, Joseph P. Colgan, Arthur W. Snoke, Matthew E. Brueseke

Department of Earth, Environment and Sustainability Faculty Publications

This field trip examines contrasting lines of evidence bearing on the timing and structural style of Cenozoic (and perhaps late Mesozoic) extensional deformation in northeastern Nevada. Studies of metamorphic core complexes in this region report extension beginning in the early Cenozoic or even Late Cretaceous, peaking in the Eocene and Oligocene, and being largely over before the onset of “modern” Basin and Range extension in the middle Miocene. In contrast, studies based on low- temperature thermochronology and geologic mapping of Eocene and Miocene volcanic and sedimentary deposits report only minor, localized extension in the Eocene, no extension at all in …

On Constrained Optimization Schemes For Joint Inversion Of Geophysical Datasets, Uram Anibal Sosa Aguirre

Open Access Theses & Dissertations

In the area of geological sciences, there exist several experimental techniques used to advance in the understanding of the Earth. We implement a joint inversion least-squares (LSQ) algorithm to characterize one dimensional Earth's structure by using seismic shear wave velocities as a model parameter. We use two geophysical datasets sensitive to shear velocities, namely Receiver Function and Surface Wave dispersion velocity observations, with a choice of an optimization method: Truncated Singular Value Decomposition (TSVD) or Primal-Dual Interior-Point (PDIP). The TSVD and the PDIP methods solve a regularized unconstrained and a constrained minimization problem, respectively. Both techniques include bounds into the …

Investigating The Influence Of Organic Acids On Uraninite Solubility And Uranyl Sorption Onto Kaolinite, Michelle L. Barger

Dissertations

Within anoxic near surface aqueous settings where U0_2(S) may be released an opportunity to encounter and complex with organic acids may occur. Reactions between U0_2(S) and ligands may promote the solubility and mobility of uranium. Organic ligands investigated in the dissolution work include citric acid, NTA and EDTA. Exposure to the ligands had little effect on U0_2(S) solubility. The log activity of U0_2(S) hydrolysis under reduced conditions was -6.56. Under all measured conditions of ligand concentration, the data consistently show an increase in uranium concentration to a median log U activity of -4.89. The observed solubility …

Different Degrees Of Partial Melting Of The Enriched Mantle Source For Plio−Quaternary Basic Volcanism, Toprakkale (Osmaniye) Region, Southern Turkey, Utku Bağci, Musa Alpaslan, Robert Frei, Mehmet Ali̇ Kurt, Abi̇di̇n Temel

Turkish Journal of Earth Sciences

The Toprakkale (Osmaniye) region, located in the Yumurtalık fault zone in southern Turkey, contains Quaternary volcanic rocks, shown by their mineralogical and petrographical features to be alkali basaltic and basanitic. These alkaline rocks are enriched in the large ion lithophile elements (LILE) Ba, Th and U, and show light rare earth element (LREE) enrichment relative to heavy rare earth element (HREE) on primitive mantle trace and rare earth element patterns that indicate different partial melting of the same source. The isotopic 87Sr/86Sr ratio is relatively low (0.703534-0.703575 for the alkali basalts and 0.703120-0.703130 for the basanites) and the 143Nd/144Nd ratio …

A New Species Of Angariid Gastropod From The Early Thanetian Of The Haymana-Polatlı Basin, Turkey, İzzet Hoşgör, Yavuz Okan

Turkish Journal of Earth Sciences

A new trochoidean species, Angaria calvii n. sp., from the early Thanetian of the Kırkkavak Formation (Haymana-Polatlı Basin, Palaeocene) in central Anatolia, is described and placed in the family Turbinidae. Previously, the oldest Cenozoic Angaria was recorded from the Early Palaeocene (Danian) in France (Paris Basin). In this paper, we report the second discovery of the oldest angariid specimens from the Thanetian sediments of the Tethys realm, a stratigraphic position which is supported by the foraminiferal-red alga assemblages at this locality.

New Data On The Dasycladales From The Lower Eocene Of Seyitgazi Region, Eskişehir, Central Turkey, Rajka Radoicic, Nazi̇re Erdem

Turkish Journal of Earth Sciences

An association of Dasycladalean algae is identified from the Lower Eocene (Ilerdian-Cuisian) of the Seyitgazi area, Western Anatolia. The association consists mostly of the genus Belzungia Morellet and Anatolia n. gen. This is the first discovery of such a rich and diversified dasycladalean flora with Belzungia in the Eocene of Central Tethys. The genus Belzungia is represented by four species: Belzungia terquemi Morellet, B. silvestrii (Pfender), B. bella (Ju Ying) Radoicic and B. pfenderae n. sp. Belzungia articles consist of whorls characterized by an assemblage of laterals, in the transversal section of which, the primary laterals are distally enlarged (sub-triangular …

Sphalerite Associated With Pyrrhotite-Chalcopyrite Ore Occurring In The Kotana Fe-Skarn Deposit (Giresun, Ne Turkey): Exsolution Or Replacement, Emi̇n Çi̇ftçi̇

Turkish Journal of Earth Sciences

The Kotana prospect is located about 30 km south of Giresun (NE Turkey). The ore mineralization is a Fe-skarn occurring within the low-grade pre-Lower Jurassic Pınarlar metamorphics, consisting of marble-phyllite intruded by the Upper Cretaceous-Eocene Aksu biotite monzogranite. The principal primary ore minerals include pyrrhotite and magnetite along with minor pyrite (I) and chalcopyrite, accompanied by trace sphalerite. Sphalerite is closely associated with chalcopyrite and to a lesser extent with hexagonal pyrrhotite. Secondary ore minerals include pyrite (II), marcasite, martite, hematite, goethite, lepidocrocite, and intermediate Fe-oxides-hydroxides. Gangue minerals are mainly calcite and quartz. Oxidation of the primary sulphides resulted in …

Late-Medieval Plagioclase-Titanaugite-Bearing Iron Slags Of The Yapraklı Area (Çankırı), Turkey, W. E. Sharp, Steven K. Mittwede

Turkish Journal of Earth Sciences

A mineralogical, mineral-geochemical and ^1^4C geochronological study of slags, previously identified as copper slags, in the Yapraklı area (Çankırı Province) of central Anatolia, has demonstrated that these are late-medieval iron slags consisting mainly of fayalite, glass, plagioclase, titanaugite, ulvöspinel and metallic iron. Because of the high lime content, relative to other medieval and Roman slags, these slags are quite anomalous in their lack of both modal and normative wüstite. Further study of these sites could shed light on the mining history and smelting methods of central Anatolia during a relatively obscure period of major socio-ethnic transition.

Geophysical Variations During The Total Solar Eclipse In 2006 In Turkey, Abdullah Ateş, Aydin Büyüksaraç, Özcan Bektaş

Turkish Journal of Earth Sciences

It has been observed that some geophysical parameters could be changed during a solar eclipse. We have therefore measured gravity and magnetic fields during solar eclipses. We also measured the gravity field during the previous eclipse on the 11^t^h of August, 1999. Gravity measurements on the 29^t^h of March, 2006 are compared with previous gravity measurements at the same location during the eclipse on the 11^t^h of August, 1999. Both showed the same behaviour during the eclipses. Gravity measurements showed fluctuations during both eclipses. A decrease in the intensity of the magnetic field was observed. Low-pass filtered magnetic data show …

Pre-Jurassic Basement Of The Greater Caucasus: Brief Overview, Mark L. Somin

Turkish Journal of Earth Sciences

The main units of the Greater Caucasus pre-Jurassic basement are represented by Svanetian and North-Caucasian domains brought together tectonically. The former includes continuous Devonian to Upper Triassic marine sequence devoid of any manifestation of Variscan orogenic activity. In contrast, within the limits of the North-Caucasian domain the Variscan events are expressed in classical form. This domain is very heterogeneous and contains both metamorphosed and unmetamorphosed formations. Till recently the former was considered by most authors to be mainly Proterozoic. New geochronological data indicate that the predominant part of these complexes is Palaeozoic in their protolith age. Lithology, P/T conditions of …

Upper Jurassic Reefs From The Russian Western Caucasus: Implications For The Eastern Black Sea, Li Guo, Stephen J. Vincent, Vladimir Lavrishchev

Turkish Journal of Earth Sciences

Exposures of Upper Jurassic reef outcrops in the Russian western Caucasus provide excellent field analogues for possible reef-complex reservoir targets imaged on seismic reflection data from the northern Shatskiy Ridge, eastern Black Sea. The reefs at outcrop can be generally grouped into coral-dominated, siliceous sponge-microbialite and microbialite types. Coral-dominated reefs occur as isolated patchy and massive forms, and can be subdivided into higher-diversity and low-diversity types. The former developed at shallow-water platform margins and in platform interiors, whilst the latter occurred in deeper-water mid-shelf settings. Siliceous sponge-microbialite and microbialite reefs occur as lenses and mounds that were restricted to deeper-water …

Evaluating The Duration Of Post-Lgm Grounding Events In The Glomar Challenger Basin Paleotrough, Eastern Basin Antarctica, Using Sediment Flux Calculations, Boluwatife Owolana

LSU Master's Theses

Previously acquired geological and geophysical data from the eastern Ross Sea outer shelf support the view that the West Antarctic Ice Sheet (WAIS) deposited three large-volume grounding zone wedges (GZWs) during the relatively short time since the onset of ice sheet retreat began at approximately 11 ka 14C BP. Here, GZW sediment volumes were estimated from seismic data correlations to evaluate the different possible durations of the individual grounding events. The two end-member fluxes used correspond to 1) a modern flux active at Whillans Ice Stream and 2) a larger flux accounting for the larger size of the drainage basin …

West Antarctic Ice Sheet Retreat Chronology Of Two Middle-Shelf Grounding-Zone Wedges In Eastern Basin, Ross Sea, Antarctica, Lenora Nicole Copeland

LSU Master's Theses

This study isolated a small number of large, in situ and reworked foraminifera from diamicts deposited in two grounding zone wedges on the middle continental shelf in Eastern Basin, Ross Sea, Antarctica. All samples were of sufficient weight to yield Holocene dates if the samples were indeed of Holocene age. Of the twelve small samples sent for radiocarbon analysis, the two heaviest were for reworked foraminifera which yielded dates of >22,200 14C BP and >22,500 14C BP. None of the other ten samples yielded radiocarbon dates. The lack of Holocene radiocarbon dates for the six in situ and four reworked …

Antarctic Plant And Phytoplankton Response To The First Phase Of The Mid Miocene Climatic Optimum At South Mcmurdo Sound, Lee Foersterling

LSU Master's Theses

The Antarctic Drilling Program (ANDRILL) recovered 1138.54 m of sub-seafloor marine sediments with 98% core recovery at the AND2-2A drill site in South McMurdo Sound. Biostratigraphy, magnetostratigraphy, and isotopic dating (Acton et al., 2008) indicated that an Early to Middle Miocene section (223-1138.54 mbsf) was recovered. This study focuses on an interval with high concentrations of palynomorphs, located between 460.57 and 403.48 mbsf and dated to 16.7 Ma to 16.2 Ma according to the updated Acton et al. (2008) ANDRILL SMS age model. Palynological results show a pronounced increase in organic microfossils between 434.01 and 431.91 mbsf, compared to levels …

Lithology And Internal Structure Of The San Andreas Fault At Depth Based On Characterization Of Phase 3 Whole-Rock Core In The San Andreas Fault Observatory At Depth (Safod) Borehole, Kelly Keighley Bradbury, James P. Evans, J. S. Chester, F. M. Chester, D. L. Kirshner

Geosciences Faculty Publications

We characterize the lithology and structure of the spot core obtained in 2007 during Phase 3 drilling of the San Andreas Fault Observatory at Depth (SAFOD) in order to determine the composition, structure, and deformation processes of the fault zone at 3 km depth where creep and microseismicity occur. A total of approximately 41 m of spot core was taken from three separate sections of the borehole; the core samples consist of fractured arkosic sandstones and shale west of the SAF zone (Pacific Plate) and sheared fine-grained sedimentary rocks, ultrafine black fault-related rocks, and phyllosilicate-rich fault gouge within the fault …

The 6 September 2009 Mw5.4 Earthquake In Eastern Albania – Fyrom Border: Focal Mechanisms, Slip Model, Shakemap, Anastasia Kiratzi

Turkish Journal of Earth Sciences

On 6 September 2009 (GMT 21:49) a moderate Mw5.4 earthquake sequence burst at the eastern border of Albania with the Former Yugoslav Republic of Macedonia (FYROM). The main shock was located ~6 km north of the epicentre of the 30 November 1967 Mw6.2 Dibra (or Debar) earthquake, which caused loss of life and considerable damage to buildings. We use broad band waveforms recorded by the Hellenic Unified Seismic Network (HUSN), which receives real-time waveforms from the neighbouring networks, to compute focal mechanisms, obtain the slip model and derive the Shake Map of the mainshock. The focal mechanisms of 18 of …

Recruiting Students Into The Earth Sciences Through Undergraduate Research, Anne E. Egger, Simon L. Klemperer

Geological Sciences Faculty Scholarship

This article discusses the challenges of recruiting undergraduate students into STEM disciplines and describes strategies which have been used to stimulate undergraduate interest in Earth sciences research at Stanford University.

Insights Into The 1968–1997 Dasht-E-Bayaz And Zirkuh Earthquake Sequences, Eastern Iran, From Calibrated Relocations, Insar And High-Resolution Satellite Imagery, R. T. Walker, E. A. Bergman, Walter Szeliga, E. J. Fielding

Faculty Scholarship for the Cascadia Hazards Institute

The sequence of seismicity in the Dasht-e-Bayaz and Zirkuh region of northeastern Iran, which includes 11 destructive earthquakes within a period of only 30 years, forms one of the most outstanding examples of clustered large and intermediate-magnitude seismic activity in the world.We perform a multiple-event relocation analysis, with procedures to remove systematic location bias, of 169 earthquakes, most of which occurred in the period 1968–2008, to better image the distribution of seismicity within this highly active part of Iran. The geographic locations of the clustered earthquakes were calibrated by the inclusion of phase arrivals from seismic stations at short epicentral …

Geothermal And Geopressure Assessment With Implications For Carbon Dioxide Sequestration, A Regional Scale Study, Lower Tuscaloosa Formation, Louisiana, Timmon Drumm

LSU Master's Theses

The Massive Sand member of the lower Tuscaloosa formation in Louisiana has the potential to be a prolific reservoir for carbon dioxide sequestration. Proximity to near-term anthropogenic carbon dioxide sources and existing infrastructure in the area make Louisiana a viable prospect for carbon capture and storage projects. The geothermal and geopressure conditions of the reservoir indicate that high carbon dioxide densities can be maintained throughout the study area, and substantial sand thicknesses were located. Subsurface depths of the top of the Massive Sand member range from roughly -2500 ft (-762 m) to over -21,000 ft (-6400 m) with a regional …

Assessment Of Black Carbon In Snow And Ice From The Tibetan Plateau And Pacific Northwest, Matthew Glen Jenkins

All Master's Theses

An ice core from Mt. Geladandong, Tibetan Plateau, spanning 1853-1983, and snow samples collected over two winters from the Cascade Mountains were analyzed for concentrations of black carbon (BC) using a Single Particle Soot Photometer (SP2). From the ice core, the high-resolution BC record displayed substantial variability, a 2-fold increase in peak concentrations from 1853-1930 to 1930-1983, and a 1.6-fold increase in average concentrations from 1853-1975 to 1975-1983. Concentrations were also higher than at two areas closer to BC sources and analyzed by the same method. In the Pacific Northwest, BC concentrations varied seasonally and annually, with the highest concentrations …

Geochemistry, Geothermobarometry And Geochronology Of High-Pressure Granulites And Implications For The Exhumation History Of Ultrahigh-Pressure Terranes: Dulan, Western China, Benjamin David Joseph Christensen

All Master's Theses

The Dulan ultrahigh-pressure (UHP) rocks of the North Qaidam terrane, Western China, represent continental crust that has been subducted ~100 km during continental collision. Adjacent granulites representing burial to ~50 km could either be overprinted eclogites or a separate high-pressure-high-temperature (HP-HT) granulite unit. Overprinted eclogites and HP-HT granulites imply different P-T-t paths for UHP rocks. Metamorphic conditions for the granulites are 750–880 °C and 14–17 kbar. Zircon U-Pb geochronology, REE patterns and Ti-in-zircon thermometry indicate an increase in temperature from ~800 °C (449 Ma) to ~900 °C (418 Ma). This temperature increase could explain the presence of granulite leucosomes and …

Surface Wave Inversion Of The Upper Mantle Velocity Structure In The Ross Sea Region, Western Antarctica, James D. Rinke

All Master's Theses

The Ross Sea in Western Antarctica is the locale of several extensional basins formed during Cretaceous to Paleogene rifting. Several seismic studies along the Transantarctic Mountains and Victoria Land Basin’s Terror Rift have shown a general pattern of fast seismic velocities in East Antarctica and slow seismic velocities in West Antarctica. This study focuses on the mantle seismic velocity structure of the West Antarctic Rift System in the Ross Embayment and adjacent craton and Transantarctic Mountains to further refine details of the velocity structure.

Teleseismic events were selected to satisfy the two-station great-circle-path method between 5 Polar Earth Observing Network …

Relationships Between Snake River Paleofloods, Occupational Patterns And Archaeological Preservation At Redbird Beach Archaeological Site In Lower Hells Canyon, Idaho, Tabitha Trosper

All Master's Theses

The Snake River basin drains 282,000 km² of the northwestern U.S. and is the largest tributary to the Columbia River. Redbird Beach, an archaeological site located in the lower Hells Canyon reach of the Snake River, contains extensive vertical exposures of archaeological materials interbedded with Snake River flood sediments. Redbird Beach formed in the lee of the Redbird Creek debris fan, is composed of interfingering deposits from large floods on the Snake River and locally-derived alluvial sediments from Redbird Creek. Through stratigraphic analyses of slackwater deposits, this study compares the temporal and spatial patterns of human occupation at Redbird …

Spatial And Interannual Variability Of Dissolved Organic Matter In The Kolyma River, East Siberia, Observed Using Satellite Imagery, Claire G. Griffin, Karen E. Frey, John Rogan, Robert M. Holmes

Geography

The Kolyma River basin in northeastern Siberia, the sixth largest river basin draining to the Arctic Ocean, contains vast reserves of carbon in Pleistocene-aged permafrost soils. Permafrost degradation, as a result of climate change, may cause shifts in riverine biogeochemistry as this old source of organic matter is exposed. Satellite remote sensing offers an opportunity to complement and extrapolate field sampling of dissolved organic matter in this expansive and remote region. We develop empirically based algorithms that estimate chromophoric dissolved organic matter (CDOM) and dissolved organic carbon (DOC) in the Kolyma River and its major tributaries in the vicinity of …

The Spatial Distribution Of Solar Radiation Under A Melting Arctic Sea Ice Cover, Karen E. Frey, Donald K. Perovich, Bonnie Light

Geography

The sea ice cover of the Chukchi and Beaufort Seas is currently undergoing a fundamental shift from multiyear ice to first-year ice. Field observations of sea ice physical and optical properties were collected in this region during June-July 2010, revealing unexpectedly complex spatial distributions of solar radiation under the melt-season ice cover. Based on our optical measurements of first-year ice, we found the under-ice light field in the upper ocean to be spatially heterogeneous and dependent on wavelength, ice thickness, and the areal and geometric distribution of melt ponded and bare ice surfaces. Much of the observed complexity in radiation …

Provenance Signature Of A Forearc Basin Modified By Spreading Ridge Subduction: Detrital Zircon Geochronology And Detrital Modes From The Paleogene Arkose Ridge Formation, Southern Alaska, Cullen Kortyna

Honors Theses

Upper Paleocene–Eocene boulder conglomerate, cross-stratified sandstone, and laminated carbonaceous mudstone of the Arkose Ridge Formation exposed in the southern Talkeetna Mountains record fluvial-lacustrine deposition proximal to the volcanic arc in a forearc basin modified by Paleogene spreading ridge subduction beneath southern Alaska. U-Pb ages of detrital zircon grains and modal analyses were obtained from stratigraphic sections spanning the 2,000 m thick Arkose Ridge Formation in order to constrain the lithology, age, and location of sediment sources that provided detritus. Detrital modes from 24 conglomerate beds and 54 sandstone thin sections aredominated by plutonic and volcanic clasts and plagioclase feldspar with …

Geology Of The Caucasus: A Review, Shota Adamia, Guram Zakariadze, Tamar Chkhotua, Nino Sadradze, Nino Tsereteli, Aleksandre Chabukiani, Aleksandre Gventsadze

Turkish Journal of Earth Sciences

The structure and geological history of the Caucasus are largely determined by its position between the still-converging Eurasian and Africa-Arabian lithospheric plates, within a wide zone of continental collision. During the Late Proterozoic-Early Cenozoic, the region belonged to the Tethys Ocean and its Eurasian and Africa-Arabian margins where there existed a system of island arcs, intra-arc rifts, back-arc basins characteristic of the pre-collisional stage of its evolution of the region. The region, along with other fragments that are now exposed in the Upper Precambrian-Cambrian crystalline basement of the Alpine orogenic belt, was separated from western Gondwana during the Early Palaeozoic …