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Thermochronology Of Mineral Grains In The Red And Mekong Rivers, Vietnam: Provenance And Exhumation Implications For Southeast Asia, Peter D. Clift, Andrew Carter, Ian H. Campbell, Malcolm S. Pringle, Nguyen Van Lap, Charlotte M. Allen, Kip V. Hodges, Mai Thanh Tan Oct 2006

Thermochronology Of Mineral Grains In The Red And Mekong Rivers, Vietnam: Provenance And Exhumation Implications For Southeast Asia, Peter D. Clift, Andrew Carter, Ian H. Campbell, Malcolm S. Pringle, Nguyen Van Lap, Charlotte M. Allen, Kip V. Hodges, Mai Thanh Tan

Faculty Publications

Sand samples from the mouths of the Red and Mekong Rivers were analyzed to determine the provenance and exhumation history of their source regions. U-Pb dating of detrital zircon grains shows that the main sources comprise crust formed within the Yangtze Craton and during the Triassic Indosinian Orogeny. Indosinian grains in the Mekong are younger (210-240 Ma) than those in the Red River (230-290 Ma), suggesting preferential erosion of the Qiangtang Block of Tibet into the Mekong. The Red River has a higher proportion of 700-800 Ma grains originally derived from the Yangtze Craton. 40Ar/ 39Ar dating of muscovite grains …


Oxygen Isotope Evidence For Subduction And Rift-Related Mantle Metasomatism Beneath The Colorado Plateau-Rio Grande Rift Transition, George Perkins, Zachary Sharp, Jane Selverstone Aug 2006

Oxygen Isotope Evidence For Subduction And Rift-Related Mantle Metasomatism Beneath The Colorado Plateau-Rio Grande Rift Transition, George Perkins, Zachary Sharp, Jane Selverstone

Earth and Planetary Sciences Faculty and Staff Publications

Spinel lherzolite and pyroxenite xenoliths from the Rio Puerco Volcanic Field, New Mexico, were analyzed for oxygen isotope ratios by laser fluorination. In lherzolites, olivine d18O values are high (+5.5 per mil), whereas d18O values for pyroxenes are low (cpx=+5.1 per mil; opx=+5.4 per mil) compared to average mantle values. Pyroxenite d18O values (cpx=+5.0 per mil; opx=+5.3 per mil) are similar to those of the lherzolites and are also lower than typical mantle oxygen isotope compositions. Texturally and chemically primary calcite in pyroxenite xenoliths is far from isotopic equilibrium with other phases, with d18O values of +21 per mil. The …


Hydrogen Isotopic Ratios Of Algal And Terrestrial Organic Matter In Lake Tulane, Florida: From A Modern Calibration To The Reconstruction Of Paleoclimatic And Paleohydrologic Conditions, Eric Charles Cross Jul 2006

Hydrogen Isotopic Ratios Of Algal And Terrestrial Organic Matter In Lake Tulane, Florida: From A Modern Calibration To The Reconstruction Of Paleoclimatic And Paleohydrologic Conditions, Eric Charles Cross

USF Tampa Graduate Theses and Dissertations

Recent sedimentary records have indicated that climate in low latitude, continental environments have varied significantly throughout the mid to late Holocene. In subtropical North America, major climatic phenomena such as the migration of the Intertropical Convergence Zone (ITCZ) and the Bermuda High have been shown to play a major role in this variability. Specifically, the northward migration of the ITCZ and the eastward position of the Bermuda High during summer months leads to warmer and wetter conditions over subtropical North America, and vice versa. A quantitative approach to understanding hydrologic dynamics (i.e. atmospheric circulation patterns, relative humidity) associated with these …


Paleoenvironmental Implications Of The Indidura Formation (Cenomanian/Turonian), Northeastern Mexico: A High Resolution Stratigraphic Study, Fabian Duque-Botero Jun 2006

Paleoenvironmental Implications Of The Indidura Formation (Cenomanian/Turonian), Northeastern Mexico: A High Resolution Stratigraphic Study, Fabian Duque-Botero

FIU Electronic Theses and Dissertations

High-resolution lithostratigraphic data from rock sequences known as the Indidura Formation near Parras de La Fuente, Coahuila, NE Mexico, led to achieve a significant improvement of our knowledge of that Formation. The results of this study indicate for the first time that the sequence at Parras de La Fuente developed from the deposition of calcareous cyanobacterial microspheroids that accumulated under perennial blooms during the Late Cenomanian through the Middle Turonian. Multi-proxy analyses included sedimentological, petrographical, scanning electron microscopy, stable isotope, trace element geochemistry, and paleontological data. The combined results allowed the correlation of δ13C and anomalies in Mo, V, and …


Reproducibility Of Geochemical And Climatic Signals In The Atlantic Coral Montastraea Faveolata, Jennifer M. Smith, Terrence M. Quinn, Kevin P. Helmle, Robert B. Halley Mar 2006

Reproducibility Of Geochemical And Climatic Signals In The Atlantic Coral Montastraea Faveolata, Jennifer M. Smith, Terrence M. Quinn, Kevin P. Helmle, Robert B. Halley

Marine Science Faculty Publications

Monthly resolved, 41‐year‐long stable isotopic and elemental ratio time series were generated from two separate heads of Montastraea faveolata from Looe Key, Florida, to assess the fidelity of using geochemical variations in Montastraea, the dominant reef‐building coral of the Atlantic, to reconstruct sea surface environmental conditions at this site. The stable isotope time series of the two corals replicate well; mean values of δ18O and δ13C are indistinguishable between cores (compare 0.70‰ versus 0.68‰ for δ13C and −3.90‰ versus −3.94‰ for δ18O). Mean values from the Sr/Ca time series differ by …


Induced-Polarization Measurements On Unconsolidated Sediments From A Site Of Active Hydrocarbon Biodegradation, Gamal Z. Abdel Aal, Lee D. Slater, Estella A. Atekwana Mar 2006

Induced-Polarization Measurements On Unconsolidated Sediments From A Site Of Active Hydrocarbon Biodegradation, Gamal Z. Abdel Aal, Lee D. Slater, Estella A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To investigate the potential role that indigenous microorganisms and microbial processes may play in altering low frequency electrical properties, induced-polarization (IP) measurements in the frequency range of 0.1 to 1000 Hz were acquired from sediment samples retrieved from a site contaminated by hydrocarbon undergoing intrinsic biodegradation. Increased imaginary conductivity and phase were observed for samples from the smear zone (contaminated with residual-phase hydrocarbon), exceeding values obtained for samples contaminated with dissolved-phase hydrocarbons, and in turn, exceeding values obtained for uncontaminated samples. Real conductivity, although generally elevated for samples from the smear zone, did not show a strong correlation with contamination. …


Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry Jan 2006

Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry

Geology Theses and Dissertations

Northward transport of the Yakutat terrane along the Transition and Queen Charlotte-Fairweather transform faults led to Neogene collision of the Yakutat terrane with the southern continental Alaska margin. Northward translation resulted in a stratigraphy that records the erosion of thermotectonic terranes along its path. The strata of the Yakutat terrane includes the Lower Oligocene to Lower Eocene Kulthieth Formation, the Upper Eocene to Lower Miocene Poul Creek Formation and the Miocene-Pleistocene Yakataga Formation. Detrital zircon fission-track (DZFT) ages from stratigraphically coordinated samples collected in the Northern Robinson Mountains yield provenance information of the units that can shed light on their …


Use Of Epa's Industrial Waste Management Evaluation Model (Iwem) To Support Beneficial Use Determinations, Jason D. Fopiano Jan 2006

Use Of Epa's Industrial Waste Management Evaluation Model (Iwem) To Support Beneficial Use Determinations, Jason D. Fopiano

Master's Theses and Capstones

As of now, the beneficial-use (recycling) of secondary materials (e.g. coal-fly ash) in highway construction is limited. In 1998 and 1999, the Association of State and Territorial Solid Waste Management Officials (ASTSWMO) conducted a Beneficial-Use Survey to determine the issues that states face when evaluating potential beneficial-use applications for recycled/secondary materials. The report identified the largest obstacle as the lack of good information for use in evaluating potential risks to human health and the environment (i.e. soil and groundwater contamination) from beneficial-use applications. The absence of such data has resulted in reluctance in the beneficial-use of such materials causing them …


Recent Extreme Events In A Tropical Stalagmite: Multi-Proxy Records And Analysis Of Ecosystem Delta Carbon-13 Value Sensitivity To Weak Climate Forcing, Amy E Benoit Frappier Jan 2006

Recent Extreme Events In A Tropical Stalagmite: Multi-Proxy Records And Analysis Of Ecosystem Delta Carbon-13 Value Sensitivity To Weak Climate Forcing, Amy E Benoit Frappier

Doctoral Dissertations

Speleothems are emerging as important and detailed chronological records of environmental change. Integrating exploration of modern speleothem records of environmental variability, related forcing factors, and understanding and suggests new potential proxies. This dissertation demonstrates the potential for developing novel proxy records of past regional environmental extremes, such as tropical cyclones, explosive volcanism, and enhanced seasonal contrasts from speleothems that are sensitive to transient infiltration events through very high-resolution, multi-parameter analysis of a rapidly growing, fracture-fed tropical stalagmite. A series of sample screening steps were developed prior to stalagmite collection in the field in order to increase the likelihood of collecting …


The Effect Of Air Pollution And Time Spent Outdoors On Pulmonary Function In A Diverse New England Population, Thomas Daniel Lambert Jan 2006

The Effect Of Air Pollution And Time Spent Outdoors On Pulmonary Function In A Diverse New England Population, Thomas Daniel Lambert

Master's Theses and Capstones

Outdoor air pollution has been associated with declines in pulmonary function. We collected daily pulmonary function measures from 165 participants in New England during July and August, 2004 and compared these measures to outdoor air pollution using single and multiple pollutant models. Increases of 10mug/m3 PM2.5, 10 ppb O3, and 1 ppb NO2 were associated with -1.29%, -0.54%, and -0.151 % changes in FEV1 of asthmatic participants spending more than 5 hours outdoors, respectively. Effects for non-asthmatic and all participants spending less than 5 hours outdoors were near zero and not significant. There was also evidence indicating that the largest …


Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay Jan 2006

Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay

Turkish Journal of Earth Sciences

The Menderes Massif, which covers a large area in western Turkey, is made up of Pan-African basement rocks and a Palaeozoic to Early Tertiary cover sequence. The study area is located in the Dalama and Hallaçlar (Aydın) area, in the northern and central parts of the Çine submassif of the Menderes Massif. The oldest units of the Pan-African basement are metaclastics, consisting of paragneisses and mica schists that gradually and conformably overlay paragneisses. Macroscopic appearances and mineralogical and textural data indicate that paragneisses can be subdivided into four subgroups. These are: (1) black spotted, (2) white spotted, (3) massive, grey-coloured …


Toward A Unified Science Of The Earth's Surface: Opportunities For Synthesis Among Hydrology, Geomorphology, Geochemistry, And Ecology, C. E. Foufoula-Georgiou, W. E. Dietrich, M. Hondzo, D. Mohrig, G. Parker, M. E. Power, I. Rodriguez-Iturbe, V. Voller, P. Wilcock Jan 2006

Toward A Unified Science Of The Earth's Surface: Opportunities For Synthesis Among Hydrology, Geomorphology, Geochemistry, And Ecology, C. E. Foufoula-Georgiou, W. E. Dietrich, M. Hondzo, D. Mohrig, G. Parker, M. E. Power, I. Rodriguez-Iturbe, V. Voller, P. Wilcock

Watershed Sciences Faculty Publications

The Earth's surface is shaped by the interaction of tectonics, water, sediment, solutes, and biota over a wide range of spatial and temporal scales and across diverse environments. Development of a predictive science of Earth surface dynamics integrates many disciplines and approaches, including hydrology, geomorphology, ocean and atmospheric science, sedimentary and structural geology, geochemistry, and ecology. This paper discusses challenges, opportunities, and a few example problems that can serve as pathways toward this integration.


Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu Jan 2006

Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu

Turkish Journal of Earth Sciences

An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content, the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr/Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for …


Application Of Paleoclimatology To Coral Reef Monitoring And Management, C. Mark Eakin, Peter K. Swart, Terrence M. Quinn, Kevin P. Helmle, Jennifer M. Smith, Richard E. Dodge Jan 2006

Application Of Paleoclimatology To Coral Reef Monitoring And Management, C. Mark Eakin, Peter K. Swart, Terrence M. Quinn, Kevin P. Helmle, Jennifer M. Smith, Richard E. Dodge

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The skeletons of reef-building corals are valuable archives of climatic and environmental information. Paleoclimatic data chiefly have been generated in areas most sensitive to global or regional climatic variability. However, these records also provide valuable information on anthropogenic influences – guidance of value to resource managers. NOAA’s Coral Reef Watch targets observations of current and past coral reef health in or near marine protected areas through satellites, in situ sensor platforms, and paleoclimatic analyses. Paleoclimatic data provide retrospective monitoring through multi-century environmental reconstructions that improve our understanding of past stress to coral reefs. Two sites in the Florida Keys National …


Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement Jan 2006

Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement

Undergraduate Review

No abstract provided.


Assessing The Potential Impact Of Microbes In The Edwards And Trinity Aquifers Of Central Texas, Kelli Willson Randall Jan 2006

Assessing The Potential Impact Of Microbes In The Edwards And Trinity Aquifers Of Central Texas, Kelli Willson Randall

LSU Master's Theses

The Edwards Aquifer in central Texas is one of the largest carbonate aquifers in the United States, supplying nearly two million people with water. The role of microorganisms in the development of deep carbonate aquifers has not been thoroughly investigated. The Edwards Aquifer is composed of a freshwater zone and a sulfidic, saline water zone. Down-well video surveys show an abundance of white filamentous and planktonic biomass floating in the water column, indicating that the saline water may serve as a habitat for microbes and provide a unique opportunity to investigate microbially enhanced deep subsurface karstification. A combination of geochemical …