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2012

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Articles 781 - 810 of 988

Full-Text Articles in Earth Sciences

Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao Jan 2012

Palaeoclimatic Estimates For The Late Pliocene Based On Leaf Physiognomy From Western Yunnan, China, Sanping Xie, Sun Bainian, Jinyu Wu, Zhicheng Lin, Defei Yan, Liang Xiao

Turkish Journal of Earth Sciences

Based on leaf physiognomy of the Late Pliocene Tuantian megaflora from the Mangbang Formation of Tengchong County in western Yunnan, a quantitative reconstruction of palaeoclimate was performed with Leaf Margin Analysis (LMA) methodology and the Climate-Leaf Analysis Multivariate Program (CLAMP). The latter produced the following parameters: mean annual temperature (MAT) from 17.2 to 17.7°C; warmest month mean temperature (WMMT) from 25 to 25.5°C; coldest month mean temperature (CMMT) from 9.5 to 10.8°C; length of growing season (GRS) from 9.5 to 9.7 months; growing season precipitation (GSP) from 1834.3 to 1901.2 mm; mean monthly growing season precipitation (MMGSP) from 222.4 to …

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Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl Jan 2012

Palaeoclimate Estimates For Selected Leaf Floras From The Late Pliocene (Reuverian) Of Central Europe Based On Different Palaeobotanical Techniques, Christine Thiel, Stefan Klotz, Dieter Uhl

Turkish Journal of Earth Sciences

To provide quantitative palaeoclimate estimates based on different palaeobotanical techniques for three contemporaneous Pliocene leaf floras, we applied the Coexistence Approach (CoA), leaf margin analysis (LMA), the Climate Leaf Analysis Multivariate Program (CLAMP) and the European Leaf Physiognomic Approach (ELPA). Furthermore, we compared recently published estimates from an additional locality with our data. The leaf physiognomic techniques yield lower mean annual temperatures than the CoA, which is most likely caused by taphonomic biases. Due to these potential biases we are in favour of the CoA as the most reliable method, and its palaeotemperature estimates show similar temperatures for all localities. …

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Sedimentary Properties Of The Middle−Upper Eocene Formations In Çardak, Burdur And İncesu, Sw Turkey, Ezher Toker, Mehmet Serkan Akki̇raz, Fuzuli̇ Yağmurlu, Funda Akgün, Sefer Örçen Jan 2012

Sedimentary Properties Of The Middle−Upper Eocene Formations In Çardak, Burdur And İncesu, Sw Turkey, Ezher Toker, Mehmet Serkan Akki̇raz, Fuzuli̇ Yağmurlu, Funda Akgün, Sefer Örçen

Turkish Journal of Earth Sciences

The integration of sedimentological, palynological and palaeontological data in three different outcrops in SW Turkey provides a clearer understanding of the palaeoenvironments in an area between the Çardak-Dazkırı Basin and the Isparta region during the Middle-Late Eocene. In this study, the Çardak-Dazkırı (Başçeşme Formation), Burdur (Varsakyayla Formation) and Isparta (Kayıköy Formation) areas have been studied for facies and facies associations. These formations contain alluvial fan, fan delta, shelf and related marine deposits. Detailed field observations allowed 34 lithofacies and 10 facies associations to be identified. The palynomorph assemblages in the Başçeşme and Varsakyayla formations contain biostratigraphically important taxa such as …

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Discovery Of A Mississippian Reef In Turkey: The Upper Viséan Microbial-Sponge-Bryozoan-Coral Bioherm From Kongul Yayla (Taurides, S Turkey), Julien Denayer, Markus Aretz Jan 2012

Discovery Of A Mississippian Reef In Turkey: The Upper Viséan Microbial-Sponge-Bryozoan-Coral Bioherm From Kongul Yayla (Taurides, S Turkey), Julien Denayer, Markus Aretz

Turkish Journal of Earth Sciences

For the first time, a Mississippian reef is described from Turkey. This microbial-sponge-bryozoan-coral bioherm has been discovered in the Central Taurides (South Turkey), at Kongul Yayla located between Hadim and Taşkent. The bioherm contains a rich and diversified fauna: sponges and rugose corals are of particular interest. The bioherm shows four main facies reflecting distinct growth stages from the base to the top: (1) the basal bioclastic beds, (2) the core facies formed of framestone comprising rugose corals, lithistid sponges, fistuliporid bryozoans and microbial boundstone, (3) the crest facies with large colonies of cerioid rugose corals and chaetetid sponges, and …

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Neotectonic Characteristics Of The İnönü-Eskişehir Fault System In The Kaymaz (Eskişehir) Region: Influence On The Development Of The Mahmudiye-Çifteler-Emirdağ Basin, Azad Selçuk, Yaşar Ergün Gökten Jan 2012

Neotectonic Characteristics Of The İnönü-Eskişehir Fault System In The Kaymaz (Eskişehir) Region: Influence On The Development Of The Mahmudiye-Çifteler-Emirdağ Basin, Azad Selçuk, Yaşar Ergün Gökten

Turkish Journal of Earth Sciences

The İnönü-Eskişehir Fault System (İEFS) is a NW- to WNW-trending zone of active deformation about 15-25 km wide, 400 km long and characterized predominatly by strike-slip faulting. In this study, the Yörükkaracaören (SE of Eskişehir)-Sivrihisar section of the İEFS was investigated. The system consists of three fault zones, namely the Alpu Fault Zone (AFZ), the Eskişehir Fault Zone (EFZ) and the Orhaniye Fault Zone (OFZ) in the study area. The EFZ is made up mostly of N30°W-trending right-lateral strike-slip fault segments with normal components. However, the AFZ and OFZ are composed of E-W-trending normal and NE- to NW-trending strike-slip fault …

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Late Palaeozoic To Cenozoic Evolution Of The Black Sea-Southern Eastern Europe Region: A View From The Russian Platform, Anatoly Nikishin, Peter Ziegler, Sergey Bolotov, Pavel Fokin Jan 2012

Late Palaeozoic To Cenozoic Evolution Of The Black Sea-Southern Eastern Europe Region: A View From The Russian Platform, Anatoly Nikishin, Peter Ziegler, Sergey Bolotov, Pavel Fokin

Turkish Journal of Earth Sciences

A synthesis of the Late Palaeozoic to Cenozoic evolution of the Black Sea region and the southern parts of the East European Platform (EEP) is presented. During Carboniferous to Early Permian times the Cordillera-type Euxinus Orogen evolved along the southern margin of the EEP in response to progressive closure of the Rheic and Palaeotethys oceans and the accretion of Gondwana-derived continental terranes. Permian development of the north-dipping Palaeotethys subduction system along the southern Pontides margin of these terranes was accompanied by important compressional intraplate deformation on the EEP. The Mesozoic to Palaeogene evolution of the southern parts of the EEP, …

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Cenozoic Volcanism Of The Caucasian Mobile Belt In Georgia, Its Geological-Petrological Peculiarities And Geodynamic Conditions, Bezhan Tutberidze Jan 2012

Cenozoic Volcanism Of The Caucasian Mobile Belt In Georgia, Its Geological-Petrological Peculiarities And Geodynamic Conditions, Bezhan Tutberidze

Turkish Journal of Earth Sciences

The Caucasian mobile belt is situated in the area of Late Cenozoic collision of the large Afro-Arabian and Eurasian lithospheric plates. Extensive volcanic activity in the Georgian part of the Caucasian mobile belt took place during the Late Miocene-Holocene. Five volcanic regions have been identified in Georgia; each of them reveals in a greater or lesser degree similarity of tectonic and magmatic processes. Volcanic products are represented by basaltic, doleritic, andesitic basaltic, andesitic dacitic, rhyolitic lavas and their pyroclastics with andesites and dacites prevailing. Using petrochemical and geochemical data the volcanics can be divided into two main rock groups: calc-alkaline …

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Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson Jan 2012

Ion Probe U-Pb Dating Of The Central Sakarya Basement: A Peri-Gondwana Terrane Intruded By Late Lower Carboniferous Subduction/Collision-Related Granitic Rocks, Petek Ayda Ustaömer, Ti̇mur Ustaömer, Alastair Robertson

Turkish Journal of Earth Sciences

Ion probe dating is used to determine the relative ages of amphibolite-facies meta-clastic sedimentary rocks and crosscutting granitoid rocks within an important 'basement' outcrop in northwestern Turkey. U-Pb ages of 89 detrital zircon grains separated from sillimanite-garnet micaschist from the Central Sakarya basement terrane range from 551 Ma (Ediacaran) to 2738 Ma (Neoarchean). Eighty five percent of the ages are 90-110% concordant. Zircon populations cluster at ~550-750 Ma (28 grains), ~950-1050 Ma (27 grains) and ~2000 Ma (5 grains), with smaller groupings at ~800 Ma and ~1850 Ma. The first, prominent, population (late Neoproterozoic) reflects derivation from a source area …

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Late Cretaceous-Eocene Geological Evolution Of The Pontides Based On New Stratigraphic And Palaeontologic Data Between The Black Sea Coast And Bursa (Nw Turkey), Zahi̇de Özcan, Aral Okay, Ercan Özcan, Aynur Hakyemez, Sevi̇nç Altiner Jan 2012

Late Cretaceous-Eocene Geological Evolution Of The Pontides Based On New Stratigraphic And Palaeontologic Data Between The Black Sea Coast And Bursa (Nw Turkey), Zahi̇de Özcan, Aral Okay, Ercan Özcan, Aynur Hakyemez, Sevi̇nç Altiner

Turkish Journal of Earth Sciences

The Late Cretaceous-Eocene geological evolution of northwest Turkey between the Black Sea and Bursa was studied through detailed biostratigraphic characterization of eleven stratigraphic sections. The Upper Cretaceous sequence in the region starts with a major marine transgression and lies unconformably on a basement of Palaeozoic and Triassic rocks in the north (İstanbul-type basement) and on metamorphic rocks and Jurassic sedimentary rocks in the south (Sakarya-type basement). Four megasequences have been differentiated in the Late Cretaceous-Eocene interval. The first one, of Turonian to Late Campanian age, is represented by volcanic and volcanoclastic rocks in the north along the Black Sea coast, …

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The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇ Jan 2012

The Unaz Formation: A Key Unit In The Western Black Sea Region, N Turkey, Okan Tüysüz, İsmai̇l Ömer Yilmaz, Lilian Svabenicka, Sabri̇ Ki̇ri̇ci̇

Turkish Journal of Earth Sciences

The Pontide magmatic belt in the Western Pontides, which developed in response to the northward subduction of the northern branches of the Tethys Ocean, consists of two different volcanic successions separated by an Upper Santonian pelagic limestone unit, the Unaz Formation. The first period of volcanism and associated sedimentation started during the Middle Turonian and lasted until the Early Santonian under the control of an extensional tectonic regime, which created horst-graben topography along the southern Black Sea region. The lower volcanic succession, the Dereköy Formation, was deposited mainly within these grabens. This extensional period probably represents the rifting of magmatic …

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Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer Jan 2012

Testing Alternative Tectono-Stratigraphic Interpretations Of The Late Palaeozoic−Early Mesozoic Karakaya Complex In Nw Turkey: Support For An Accretionary Origin Related To Northward Subduction Of Palaeotethys, Alastair Robertson, Ti̇mur Ustaömer

Turkish Journal of Earth Sciences

Lower Carboniferous-Upper Triassic rocks of the Karakaya Complex exposed E-W across Turkey are critical to reconstructions of Palaeotethys in the Eastern Mediterranean region. Despite decades of research, the origin and emplacement of the Karakaya Complex remains controversial because it is mapped either as an overall stratigraphic succession of sedimentary olistostromes or as a stack of thrust sheets and mélange. Tectonic models include a continental rift, a back-arc rift, a marginal oceanic basin, and an accretionary prism formed by subduction of a wide ocean. Subduction is seen as either northwards or southwards. To test the alternatives, the various litho-tectonic units and …

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Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör Jan 2012

Petrogenesis Of Late Cretaceous Adakitic Magmatism In The İstanbul Zone (Çavuşbaşı Granodiorite, Nw Turkey), Sabah Yilmaz Şahi̇n, Namik Aysal, Yildirim Güngör

Turkish Journal of Earth Sciences

The Çavuşbaşı granodiorite intrudes Ordovician sedimentary rocks in the western part of the İstanbul Zone (NW Turkey). The intrusion is made up mainly of granodiorite, and subordinate tonalite and quartz diorite, and has a granular texture and some special mixing textures such as antirapakivi, blade-shaped biotite, acicular apatite, spongy cellular dissolution/melting plagioclase textures. The main mafic minerals are hornblende and biotite. U-Pb in-situ dating of zircons from two samples via SHRIMP yielded weighted age values of ~68 Ma, suggesting emplacement during the Late Cretaceous. Geochemically the Çavuşbaşı granodiorite resembles adakites with high Sr/Y and La/Yb ratios, low Y and HREE …

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Sources Of Salinization Of The Baton Rouge Aquifer System: Southeastern Louisiana, Callie Elizabeth Anderson Jan 2012

Sources Of Salinization Of The Baton Rouge Aquifer System: Southeastern Louisiana, Callie Elizabeth Anderson

LSU Master's Theses

A major environmental and economic problem confronting the Baton Rouge area, southeastern Louisiana, is the progressive salinization of the Baton Rouge aquifer system, an important source of fresh municipal and industrial groundwater. The Baton Rouge fault marks a boundary between fresh groundwaters to the north and predominately brackish waters to the south. Determining the permeability architecture of the fault is an essential component of modeling groundwater flow and saline contamination north of the fault. Understanding the sources and pathways of the saline waters that are migrating into the freshwater sands north of the fault is thus essential in helping to …

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Standardized Precipitation Index: User Guide, Mark Svoboda, Michael Hayes, Deborah Wood Jan 2012

Standardized Precipitation Index: User Guide, Mark Svoboda, Michael Hayes, Deborah Wood

National Drought Mitigation Center: Faculty Publications

Over the years, there has been much discussion on what drought indices should be used in a particular climate and for what application. Many drought definitions and indices have been developed and attempts have been made to provide some guidance on this issue. With this in mind, the Interregional Workshop on Indices and Early Warning Systems for Drought was organized and held at the University of Nebraska-Lincoln, United States of America, from 8 to 11 December 2009. It was jointly sponsored by the School of Natural Resources (SNR) of the University of Nebraska, the United States National Drought Mitigation Center …

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Growth Of Extensional Faults And Folds During Deposition Of An Evaporite-Dominated Half-Graben Basin; The Carboniferous Billefjorden Trough, Svalbard, Alvar Braathen, Karoline Bælum, Harmon Maher Jr., Simon J. Buckley Jan 2012

Growth Of Extensional Faults And Folds During Deposition Of An Evaporite-Dominated Half-Graben Basin; The Carboniferous Billefjorden Trough, Svalbard, Alvar Braathen, Karoline Bælum, Harmon Maher Jr., Simon J. Buckley

Geography and Geology Faculty Publications

Normal-sense movements along two major strands of the Billefjorden Fault Zone controlled sedimentation in the Carboniferous Billefjorden Trough. The Billefjorden Trough is a more than 2000 meters thick, west-dipping half-graben basin where accommodation was provided by combinations of extensional faulting and folding throughout the basin history. Whereas previous workers have interpreted several of these folds as due to Tertiary contraction, we argue that they developed during rifting, as extensional forced folds in the style described by other workers from rifts such as the Gulf of Suez. The present basin geometry indicates that accommodation was facilitated by a combination of fault …

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Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman Jan 2012

Great Plains Soils May Be C Sinks, David E. Clay, Gregg C. Carlson, Sharon A. Clay, James Stone, Kurtis Reitsma, Ronald Gelderman

Agronomy, Horticulture and Plant Science Faculty Publications

Numerous studies with wide-ranging results have been conducted to resolve if Great Plains soils are a C source or sink. The authors addressed the source/sink question by examining the results from producer soil samples and production surveys that were analyzed and archived by the South Dakota Soil Testing Laboratory. Results showed that between 1985 and 2010, soil organic C content increased at a rate of 326 lb C/A/year, for a total increase of 24%. The increase was attributed to planting better adapted varieties and using better management practices that on average increased corn grain yields 2.29 bu/A/year. Higher soil organic …

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Net Ecosystem Production (Nep) Of The Great Plains, United States, Daniel Howard, Tagir Gilmanov, Yingxin Gu, Bruce Wylie, Li Zhang Jan 2012

Net Ecosystem Production (Nep) Of The Great Plains, United States, Daniel Howard, Tagir Gilmanov, Yingxin Gu, Bruce Wylie, Li Zhang

Natural Resource Management Faculty Publications

Gross primary production (GPP) and ecosystem respiration (Re) are the fundamental environmental characteristics that promote carbon exchanges with the atmosphere (Chapin and others, 2009), although other exchanges of carbon, such as direct oxidation (Lovett and others, 2006), can modify net ecosystem production (NEP). The accumulation of carbon in terrestrial ecosystems results in systems in which soil organic matter (SOM) carbon often exceeds biomass carbon (Post and Kwon, 2000). This SOM pool exists at a steady state between GPP and Re in ecosystems unless drivers change or the ecosystem endures environmental perturbations (for example, climatic). As indicated by Wilhelm and others …

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Stratigraphy And Paleoenvironments Of The Soeginina Beds (Paadla Formation, Lower Ludlow, Upper Silurian) On Saaremaa Island, Estonia, Richa N. Ekka Jan 2012

Stratigraphy And Paleoenvironments Of The Soeginina Beds (Paadla Formation, Lower Ludlow, Upper Silurian) On Saaremaa Island, Estonia, Richa N. Ekka

Senior Independent Study Theses

The Soeginina Beds in the Paadla Formation on the island of Saaremaa, western Estonia, are a lower Ludlow (Upper Silurian) sequence of dolostones, marls, and stromatolites. They represent rocks just above the Wenlock/Ludlow boundary, which is distinguished by a major disconformity that can be correlated to a regional regression on the paleocontinent of Baltica. The depositional environments of the Soeginina Beds include a shelfal environment, restricted shallow marine setting, intertidal mudflat and finally a hypersaline supratidal setting. The evidence includes halite crystal molds, oscillation ripples, eurypterid fragments, stromatolites, ostracods, gastropods, Chondrites trace fossils, intraclasts and oncoids. Nautiloid conchs are common, …

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Integrated Chemostratigraphy And Paleoceanography Of The Mississippian Barnett Formation, Krystin Chantel Robinson Jan 2012

Integrated Chemostratigraphy And Paleoceanography Of The Mississippian Barnett Formation, Krystin Chantel Robinson

Earth & Environmental Sciences Theses - Archive

The Barnett Formation was deposited on a gently sloping marine margin that ultimately became the Fort Worth Basin (FWB), a foreland basin that evolved during the late Paleozoic Era. The FWB formed as a result of the early Ouachita Orogeny, due to the collision of Laurasia and Gondwana. The Mississippian Barnett Formation is an organic-rich lithologic unit composed primarily of laminated siliceous mudrock with some calcareous mudrock intervals. The objective of the project is to develop and interpret stratigraphic changes in the geochemistry of the Barnett Formation for the purposes of understanding the paleoceanography of the northernmost Fort Worth Basin, …

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Interseismic Strain Accumulation Along The Western Boundary Of The Indian Subcontinent, Walter Szeliga, Roger Bilham, Din Mohammad Kakar, Sarosh H. Lodi Jan 2012

Interseismic Strain Accumulation Along The Western Boundary Of The Indian Subcontinent, Walter Szeliga, Roger Bilham, Din Mohammad Kakar, Sarosh H. Lodi

Faculty Scholarship for the Cascadia Hazards Institute

Despite an overall sinistral slip rate of approximately 3 cm/yr, few major earthquakes have occurred in the past 200 years along the Chaman fault system, the western boundary of the India Plate with the Eurasia Plate. GPS and InSAR data reported here indicate sinistral shear velocities of 8-17 mm/yr across the westernmost branches of the fault system, suggesting that a significant fraction of the plate boundary slip is distributed in the fold and fault belt to the east. At its southernmost on-land segment, near the triple junction between the Arabia, Eurasia, and India Plates, we find the velocity across the …

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Mapping Of The Oil Window In The Eagle Ford Shale Play Of Southwest Texas Using Thermal Modeling And Log Overlay Analysis, Austin Pourciau Cardneaux Jan 2012

Mapping Of The Oil Window In The Eagle Ford Shale Play Of Southwest Texas Using Thermal Modeling And Log Overlay Analysis, Austin Pourciau Cardneaux

LSU Master's Theses

The Eagle Ford formation in South Texas has been an established hydrocarbon play since 2008. The Eagle Ford is considered an unconventional resource because it is a source, reservoir, and seal. Hydraulic fracturing and horizontal drilling have enabled this play. As drilling and production continue the limits of this play are being defined. The area between dry gas and wet gas/condensate has been known for some time since the initial production started in dry gas and moved up-dip. After the oil window was discovered, the contact between wet gas/condensate started to become more defined. Now companies are beginning to delineate …

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Depositional Environments Of Upper Meiocene Through Pleistocene Siliciclastic Sediments, Baton Rouge Aquifer System, Southeastern Louisiana, Elizabeth Laurel Chamberlain Jan 2012

Depositional Environments Of Upper Meiocene Through Pleistocene Siliciclastic Sediments, Baton Rouge Aquifer System, Southeastern Louisiana, Elizabeth Laurel Chamberlain

LSU Master's Theses

Saltwater encroachment northward into freshwater sands of the Baton Rouge aquifer system, southeast Louisiana, poses a serious environmental threat to the metropolitan water source. The aquifer consists of a 0.6 mile-thick succession of interbedded, unconsolidated south-dipping siliciclastic sandy units and confining mudstones dating from the Upper Miocene through the Pleistocene. The study area is crosscut by the Baton Rouge fault, a west-east trending listric fault that serves as a leaky barrier to saltwater intrusion from the south. A better understanding of the connectivity, morphology and depositional setting of this aquifer system and hydraulic properties of the Baton Rouge fault is …

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Thermal And Pore Pressure History Of The Haynesville Shale In North Louisiana: A Numerical Study Of Hydrocarbon Generation, Overpressure, And Natural Hydraulic Fractures, William C. Torsch Jan 2012

Thermal And Pore Pressure History Of The Haynesville Shale In North Louisiana: A Numerical Study Of Hydrocarbon Generation, Overpressure, And Natural Hydraulic Fractures, William C. Torsch

LSU Master's Theses

New drilling technology has led to a revival of drilling in mature petroleum basins such as the Haynesville Formation in east Texas and north Louisiana. In north Louisiana, the Upper Jurassic (Kimmeridgian) aged Haynesville shale has a basinward SW dip and is located at depths ranging from around 10,500 ft to the northeast and 14,000 ft to the southwest with local minimums at the Sabine and Monroe Uplifts. Formation thickness ranges from 100 to 400 feet. Prolific natural gas production is attributed to relatively high average porosity (8 to 14%) and a high geopressure gradient > 0.9 psi/ft. (Wang and Hammes, …

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Magnetostratigraphy Susceptibility Correlations For The Guadalupian-Lopingian Boundary And The Placement Of The North American Ochoan Series: Texas (Usa) And South China, Matthew Allan Clark Jan 2012

Magnetostratigraphy Susceptibility Correlations For The Guadalupian-Lopingian Boundary And The Placement Of The North American Ochoan Series: Texas (Usa) And South China, Matthew Allan Clark

LSU Master's Theses

Stratigraphic studies have emphasized the use of multiple, geochemical and geochemical proxies to investigate critical geologic boundaries, events and their correlation throughout the entire Phanerozoic. In this study, an emerging geophysical proxy, mass-specific, low-field magnetic susceptibility (χ) is used to investigate the global correlation of the Guadalupian-Lopingian (G-L) boundary, to better resolve and supplement biostratigraphic correlations, including inferred G-L boundary sections defining the base of the North American Ochoan Series. The North American Ochoan Series of West Texas, defined lithostratigraphically by the contact between the Bell Canyon and Castile Formations, represents a unique and well-studied sequence in the Delaware Basin, …

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Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis Jan 2012

Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis

Theses and Dissertations

The Deccan Plateau in western and central India has been a major area of interest for researchers since the 1800s. In 1840, James Sowerby described the molluscan collection sent to him by John Malcolmson. In 1860, Stephen Hislop identified new molluscan species and redescribed based on better preserved material. Although this seminal work was comprehensive, interpretations have changed since the mid 1800s. Species need to be reassigned to current and/or accurate taxa, as well as revalidated statistically. Seventeen character traits were measured on over 600 specimens from five eastern Deccan Plateau localities representing a stratigraphic and temporal sequence. Cluster analysis …

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Diagenesis Of The Middle Member Of The Bakken Formation, Williston Basin, North Dakota, Katharine L. Kimber Jan 2012

Diagenesis Of The Middle Member Of The Bakken Formation, Williston Basin, North Dakota, Katharine L. Kimber

Theses and Dissertations

The shales of the Bakken Formation have been extensively studied since the discovery of oil, but little attention has been paid to the middle reservoir member. Successfully produced wells are concentrated in multiple fields throughout the Williston Basin, there has been no definitive way to determine a well’s potential productivity. This study used core samples, point counting, and petrography to determine the diagenetic traits common to the Middle Member of the Bakken Formation and their effect on oil production. Cores from forty-one wells were examined. Thin sections were made from sixteen cores, eight producing wells and eight dry wells. All …

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Study On Underground Coal Gasification Combined Cycle Coupled With On-Site Carbon Capture And Storage, Peng Pei Jan 2012

Study On Underground Coal Gasification Combined Cycle Coupled With On-Site Carbon Capture And Storage, Peng Pei

Theses and Dissertations

The North Dakota portion of the Williston basin holds huge, but economically unmineable lignite resources in the Fort Union formation. A technology coupling the underground coal gasification with carbon capture and storage (UCG-CCS) is proposed in this study to recover these lignite resources in North Dakota. The UCG-CCS system provides a cost-effective and environment-friendly approach to convert the lignite to electricity and beneficially utilize the by-product of CO2 at the same time. The target coal seam is the Harmon lignite in the Fort Union formation in western North Dakota. The main objectives of this study are to set up the …

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Variability And Trends Of Aerosol Properties Over Kanpur, Northern India Using Aeronet Data (2001–10), Dimitris G. Kaskaoutis, Ramesh P. Singh, Ritesh Gautam, Manish Sharma, P. G. Kosmopoulos, S. N. Tripathi Jan 2012

Variability And Trends Of Aerosol Properties Over Kanpur, Northern India Using Aeronet Data (2001–10), Dimitris G. Kaskaoutis, Ramesh P. Singh, Ritesh Gautam, Manish Sharma, P. G. Kosmopoulos, S. N. Tripathi

Mathematics, Physics, and Computer Science Faculty Articles and Research

Natural and anthropogenic aerosols over northern India play an important role in influencing the regional radiation budget, causing climate implications to the overall hydrological cycle of South Asia. In the context of regional climate change and air quality, we discuss aerosol loading variability and trends at Kanpur AERONET station located in the central part of the Indo-Gangetic plains (IGP), during the last decade (2001-10). Ground-based radiometric measurements show an overall increase in column-integrated aerosol optical depth (AOD) on a yearly basis. This upward trend is mainly due to a sustained increase in the seasonal/monthly averaged AOD during the winter (Dec-Feb) …

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Successful Genotyping Of Microsatellites In The Woolly Mammoth, Yasuko Ishida, Alfred L. Roca, Stephen Fratpietro, Alex D. Greenwood Jan 2012

Successful Genotyping Of Microsatellites In The Woolly Mammoth, Yasuko Ishida, Alfred L. Roca, Stephen Fratpietro, Alex D. Greenwood

Biological Sciences Faculty Publications

Genetic analyses using ancient DNA from Pleistocene and early Holocene fossils have largely relied on mitochondrial DNA (mtDNA) sequences. Among woolly mammoths, Mammuthus primigenius, mtDNA analyses have identified 2 distinct clades (I and II) that diverged 1-2 Ma. Here, we establish that microsatellite markers can be effective on Pleistocene samples, successfully genotyping woolly mammoth specimens at 2 loci. Although significant differentiation at the 2 microsatellite loci was not detected between 16 clade I and 4 clade II woolly mammoths, our results demonstrate that the nuclear population structure of Pleistocene species can be examined using fast-evolving nuclear microsatellite markers.

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Riverine Breach And Subsequent Decant Of An Acidic Pit Lake: Evaluating The Effects Of Riverine Flow-Through On Lake Stratification And Chemistry, C. D. Mccullough, Naresh Radhakrishnan, Mark Lund, Michelle Newport, Elmien Ballot, Digby Short Jan 2012

Riverine Breach And Subsequent Decant Of An Acidic Pit Lake: Evaluating The Effects Of Riverine Flow-Through On Lake Stratification And Chemistry, C. D. Mccullough, Naresh Radhakrishnan, Mark Lund, Michelle Newport, Elmien Ballot, Digby Short

Research outputs 2012

Breach and subsequent decant of an acidic brackish pit lake in the Collie Coal region in south-western Australia occurred during flooding of a pre-mining diverted eutrophic river. Inflowing fresher river water with high alkalinity and nutrient concentrations settled over more saline and acidic pit lake water. This created a halocline with better mixoliminion water quality and monimolimnion water quality typical of the pre-breach lake. Flow-through may represent the best long-term mine closure option for this and other pit lakes in the state and internationally where pit lake water quality degrades over time when excised from regional water systems.

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