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Articles 1051 - 1080 of 1547
Full-Text Articles in Earth Sciences
Five Year Carbon Storage Analysis In The Gordon Natural Area, Joy Fritschle, Chad Hudson, Catherine Spahr, Andy Tamez
Five Year Carbon Storage Analysis In The Gordon Natural Area, Joy Fritschle, Chad Hudson, Catherine Spahr, Andy Tamez
Forest Carbon Storage Study Documents
The Gordon Natural Area (GNA) serves as a natural laboratory for a range of class research projects. In a Geography Field Methods course led by Dr. Fritschle, students established five permanent carbon-study plots in 2008. Since then, students have returned to these plots to measure the carbon stock of standing trees in five plots located along a topographic gradient: floodplain, ridge-top, lower mid-slope, mid-slope and upper mid-slope. Using U.S. Forest Service established guidelines, all trees greater than 5 cm and up to 73 cm in diameter at breast height (DBH) were measured and identified within each 40 m circular plot. …
Oil Pollution In Water Bodies Of Restricted Circulation, Michael A. Kruge
Oil Pollution In Water Bodies Of Restricted Circulation, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Coastal lagoons and embayments near urban centers around the world share many common characteristics and problems. Physical impediments to free water circulation (spits, barrier islands, internal islands, tombolos, submerged sills) often lead to water stagnation and, in the presence of excess nutrients, eutrophication. Urban and industrial activities provoke (usually accidental) spills of hazardous materials into these confined water bodies, such as crude petroleum and refined petroleum products, leading to difficulties for resident biota and potential hazards for human health. The sluggish turnover of these water bodies (or low-energy zones within them) may retard the natural attenuation of the spilled contaminants. …
Chemostratigraphy Of The Early Pliocene Diatomite Interval From Mis And-1b Core (Antarctica): Paleoenvironment Implications, Giovanna Scopelliti, Adriana Bellanca, Donata Monien, Gerhard Kuhn
Chemostratigraphy Of The Early Pliocene Diatomite Interval From Mis And-1b Core (Antarctica): Paleoenvironment Implications, Giovanna Scopelliti, Adriana Bellanca, Donata Monien, Gerhard Kuhn
ANDRILL Research and Publications
The AND-1B drill core (1285 m-long) was recovered, inside the ANDRILL (ANtarctic geological DRILLing) Program, during the austral summer of 2006/07 from beneath the floating McMurdo Ice Shelf. Drilling recovered a stratigraphic succession of alternating diamictites, diatomites and volcaniclastic sediments spanning about the last 14 Ma. A core portion between 350 and 480 mbsf, including a 80 m-thick diatomite interval recording the early Pliocene warming event, was investigated in term of opal biogenic content and element geochemistry. Across the diatomite interval, in spite of the lithological uniformity, a fluctuating biogenic opal profile mirrors the δ18O record, testifying a decrease in …
Geo402/585: Field Methods; Labs 4-5 Gordon Natural Area Carbon Stock Pilot Study, Joy Fritschle
Geo402/585: Field Methods; Labs 4-5 Gordon Natural Area Carbon Stock Pilot Study, Joy Fritschle
Gordon Natural Area-related Curricula Documents
No abstract provided.
Water Column Variability In A Coastal Tourist Cave In Mallorca, Spain, Liana M. Boop, Bogdan P. Onac, Jonathan G. Wynn, Joan J. Fornós, Marta Rodríguez-Homar
Water Column Variability In A Coastal Tourist Cave In Mallorca, Spain, Liana M. Boop, Bogdan P. Onac, Jonathan G. Wynn, Joan J. Fornós, Marta Rodríguez-Homar
National Cave and Karst Management Symposium 2013
Coves del Drac is visited by more than 1 million tourists annually and has been a tourist destination in the western Mediterranean for over 100 years. All areas of the cave are developed with historic or current tour route infrastructure, including walkways, handrails, and electric lighting. This study compares one vertical water profile collected along the current tour path with two other profiles from historic tour route locations. Differences in freshwater and organic inputs, as well as direct anthropogenic impacts, are clearly observed in the aquatic parameters and stable isotopes collected in the profiles. Anthropogenically-driven undersaturation in the cave pools, …
Modeling Of Co2-Water-Rock Interactions In A Mississippian Sandstone Reservoir Of Kentucky, Anne M. Schumacher
Modeling Of Co2-Water-Rock Interactions In A Mississippian Sandstone Reservoir Of Kentucky, Anne M. Schumacher
Theses and Dissertations--Earth and Environmental Sciences
This study examined CO2-water-rock interactions occurring during a carbon sequestration pilot test into a Mississippian oil reservoir in western Kentucky. New samples (n=62) and archived data, both collected from oil wells, were used to characterize the chemistry of formation waters from the Sugar Creek field in Hopkins County. In addition, core and cuttings samples (n=17) from the reservoir and overlying cap-rocks in, or near, the field were analyzed for bulk and clay mineralogy using X-ray diffraction. Electric logs were used to select sample intervals within the overlying cap-rocks and the center of the producing zones in the Jackson …
Effects Of Chiloquin Dam On Spawning Distribution And Larval Emigration Of Lost River, Shortnose, And Klamath Largescale Suckers In The Williamson And Sprague Rivers, Oregon, Barbara A. Martin, David A. Hewitt, Craig M. Ellsworth
Effects Of Chiloquin Dam On Spawning Distribution And Larval Emigration Of Lost River, Shortnose, And Klamath Largescale Suckers In The Williamson And Sprague Rivers, Oregon, Barbara A. Martin, David A. Hewitt, Craig M. Ellsworth
United States Geological Survey: Publications
Chiloquin Dam was constructed in 1914 on the Sprague River near the town of Chiloquin, Oregon. The dam was identified as a barrier that potentially inhibited or prevented the upstream spawning migrations and other movements of endangered Lost River (Deltistes luxatus) and shortnose (Chasmistes brevirostris) suckers, as well as other fish species. In 2002, the Bureau of Reclamation led a working group that examined several alternatives to improve fish passage at Chiloquin Dam. Ultimately it was decided that dam removal was the best alternative and the dam was removed in the summer of 2008. The U.S. …
The Mineral Industry Of Nebraska
The Mineral Industry Of Nebraska
United States Geological Survey: Publications
In 2013, the value of the nonfuel mineral production1 in the State of Nebraska was $166 million,2 0.2% of the total U.S. nonfuel mineral production, ranking it 39th in the country. In 2012, the corresponding value was $160 million,2 0.2% of the Nation’s total nonfuel mineral production, ranking it 36th among the 50 States. In 2013, on a per capita basis, nonfuel mineral production in Nebraska in 2013 had a value of $89 compared with the national average of $238. In 2012, the per capita value was $86 compared with the national average of $241. The value of nonfuel mineral …
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Wayne State University Theses
The Porcupine Mining Camp located in the southwestend of the Abitibi Greenstone Belt has been mined extensively for its prolific precious and base metal enrichment. This study targeted Bristol and Northern Thorneloe, fifteen kilometers southwest of Timmins, ON, an area that is of economic interest for its gold mineralization. Rock samples were collected (drill- core and outcrop) throughout both townships and analyzed for their major and trace element composition, These were used to determine hydrothermal alteration signatures as well as specific elemental enrichment that relate to gold mineralization in Bristol-Thorneloe Township. Quartz-carbonate and quartz-carbonate-tourmaline vein samples were also collected near …
The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack
The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack
Chemistry & Biochemistry Faculty Publications
Seepage of coal-bed methane (CBM) through soils is a potential source of atmospheric CH4 and also a likely source of ancient (i.e. 14C-dead) carbon to soil microbial communities. Natural abundance 13C and 14C compositions of bacterial membrane phospholipid fatty acids (PLFAs) and soil gas CO2 and CH4 were used to assess the incorporation of CBM-derived carbon into methanotrophs and other members of the soil microbial community. Concentrations of type I and type II methanotroph PLFA biomarkers (16:1ω8c and 18:1ω8c, respectively) were elevated in CBM-impacted soils compared with a control site. Comparison …
Distribution And Impacts Of Petroleum Hydrocarbons In Louisiana Tidal Marsh Sediments Following The Deepwater Horizon Oil Spill, Rachel S. Hatch
Distribution And Impacts Of Petroleum Hydrocarbons In Louisiana Tidal Marsh Sediments Following The Deepwater Horizon Oil Spill, Rachel S. Hatch
Theses and Dissertations--Earth and Environmental Sciences
Following the 2010 Deepwater Horizon (DWH) spill, sediment cores were analyzed from marshes at various levels of oiling to determine how deeply oil penetrated sediment in these marsh environments, and if at these sites it had quantifiably affected benthic ecosystems. Minimum mixing depths were determined from penetration of the lithogenic radionuclide 234Th, which ranged from 0.25 to 4.5 cm. Sediment accumulation rates were determined using 210Pb, with verification from 137Cs in selected cores. Lead-210 profiles revealed long-term (decadal) mixing. Bay Jimmy, Louisiana was significantly affected by the DWH oil spill, as indicated by total polycyclic aromatic hydrocarbon …
Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay
Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay
USF Tampa Graduate Theses and Dissertations
Modeling chemical environments is an important step to understanding the diversity of prebiotic systems that may have formed on the early earth or potentially can occur on other worlds. By using the modern Earth as a test case, these models predict scenarios with systems more conducive to the formation of the organic molecules that are important to life. Here we use the equilibrium thermodynamic modeling program HSC Chem to investigate prebiotic environments. This program uses the raw material that the user inputs into the system in order to calculate the change in amounts of chemical species forming as a function …
Abiotic Nitrate And Nitrite Reactivity With Iron Oxide Minerals, Prakash Dhakal
Abiotic Nitrate And Nitrite Reactivity With Iron Oxide Minerals, Prakash Dhakal
Theses and Dissertations--Plant and Soil Sciences
Under iron (Fe3+)-reducing conditions where aqueous Fe2+ and unreduced solid Fe3+-oxides commonly coexist, soil Fe2+ oxidation has been shown to be coupled with nitrate (NO3-) reduction. One possible secondary reaction is the involvement of NO3- and nitrite (NO2-) with Fe-oxide minerals found in many natural environments. Yet, spectroscopic measurements and kinetic data on reactivity of NO3- and NO2- with Fe-containing oxide minerals such as goethite (a-FeOOH), and magnetite (Fe3O4) are not found in the literature. The reactivity of …
Are 34s-Enriched Authigenic Sulfide Minerals A Proxy For Elevated Methane Flux And Gas Hydrates In The Geologic Record?, Walter S. Borowski, Nancy M. Rodriguez, Charles K. Paull, William Ussler Iii
Are 34s-Enriched Authigenic Sulfide Minerals A Proxy For Elevated Methane Flux And Gas Hydrates In The Geologic Record?, Walter S. Borowski, Nancy M. Rodriguez, Charles K. Paull, William Ussler Iii
EKU Faculty and Staff Scholarship
The sulfate–methane transition (SMT) zone is a diagenetic transition within anoxic marine sediments created by the metabolic activity of a consortium of sulfate-reducing bacteria and methane-oxidizing Archaea. As interstitial dissolved sulfate is consumed by microbially mediated sulfate reduction of sedimentary organic matter (SOM) and anaerobic oxidation of methane (AOM) large enrichments of 34S occur in the interstitial sulfate pool. These isotopic enrichments are transmitted to the dissolved sulfide pool (∑HS−) and subsequently into sulfide minerals (So, ∼FeS, FeS2).
We investigate the sulfur isotopic composition of pore-water sulfate and sulfide minerals at three sites underlain …
Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez
Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez
Open Access Theses & Dissertations
No abstract provided.
In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar
In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar
Open Access Theses & Dissertations
Zircon data from South Karakoram gneiss dome provide evidence for Proterozoic inherited cores (1.8-1.9 Ga and 2.3-.2.5 Ga) surrounded by migmatitic overgrowth with ages ranging from ~6 to ~20Ma. Oxygen isotopic data of Neogene migmatite and inherited core is similar and indistinguishable ranging from 7.5 to 9.5 /. However, Neogene overgrowth is significantly less evolved than the inherited core in terms of Hf composition. This implies that the Hf composition of the migmatitic zircons is not controlled exclusively by the dissolution of the inherited cores and that contamination by external melts is likely. Isotopic data from the Baltoro plutonic unit …
Stromatolites And Miss—Differences Between Relatives, N. Noffke, S. M. Awramik
Stromatolites And Miss—Differences Between Relatives, N. Noffke, S. M. Awramik
OES Faculty Publications
Benthic microorganisms form highly organized communities called “biofilms.” A biofilm consists of the individual cells plus their extracellular polymeric substances (EPS). In marine and non-marine environments, benthic microbial communities interact with the physical sediment dynamics and other factors in the environment in order to survive. This interaction can produce distinctive sedimentary structures called microbialites. Binding, biostabilization, baffling, and trapping of sediment particles by microorganisms result in the formation of microbially induced sedimentary structures (MISS); however, if carbonate precipitation occurs in EPS, and these processes happen in a repetitive manner, a multilayered build-up can form—stromatolites. Stromatolites and MISS are first found …
Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski
Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski
International Journal of Speleology
Dynamics and drivers of ventilation in caves are of growing interest for different fields of science. Accumulated CO2 in caves can be exchanged with the atmosphere, modifying the internal CO2 content, affecting stalagmite growth rates, deteriorating rupestrian paintings or creating new minerals. Current estimates of cave ventilation neglect the role of high CO2 concentrations in determining air density – approximated via the virtual temperature (Tv) –, affecting buoyancy and therefore the release or storage of CO2. Here we try to improve knowledge and understanding of cave ventilation through the use of T …
Natural And Anthropogenic Factors Which Influence Aerosol Distribution In Ingleborough Show Cave, Uk, Andrew C. Smith B.S.C, Peter M. Wynn, Philip A. Barker Professor
Natural And Anthropogenic Factors Which Influence Aerosol Distribution In Ingleborough Show Cave, Uk, Andrew C. Smith B.S.C, Peter M. Wynn, Philip A. Barker Professor
International Journal of Speleology
Monitoring in Ingleborough Show Cave (N. Yorkshire, UK) reveals the influence of tourism and cave management techniques on different parameters of the cave atmosphere. Exploratory aerosol monitoring identified a 0.015 ± 0.03 mg/m³ (≈70%) reduction in airborne particulates within the first 75 meters of cave passage and two major aerosol sources within this artificially ventilated show cave. Autogenic aerosol production was identified close to active stream ways (increases of
A Model For The Formation Of Layered Soda-Straw Stalactites, Bence Paul, Russell Drysdale, Helen Green, Jon Woodhead, John Hellstrom, Rolan Eberhard
A Model For The Formation Of Layered Soda-Straw Stalactites, Bence Paul, Russell Drysdale, Helen Green, Jon Woodhead, John Hellstrom, Rolan Eberhard
International Journal of Speleology
Climate records based upon instrumental data such as rainfall measurements are usually only available for approximately the last 150 years at most. To fully investigate decadal-scale climate variation, however, these records must be extended by the use of climate proxies. Soda-straw stalactites (straws) are a previously under-utilised potential source of such data. In this contribution we investigate the structure and formation of straws and look at some issues that may affect the reliability of straw-based palaeoclimate records. We use laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) trace element analysis to document surface contamination features that have the potential to obscure annual …
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
Geochemical Evidence For Vertical Migration Of Deep Formation Fluids Through The Baton Rouge -Denham Springs Fault System, Lesley C. Prochaska
LSU New Orleans Theses and Dissertations
Accumulations of brackish groundwater exist across south Louisiana within the shallow, south-dipping Pleistocene to Upper Miocene Baton Rouge Aquifer System (BRAS). This research investigates the source of brackish groundwater through geochemical analysis of representative groundwater samples by comparing the following geochemical ratios along with other trace elements. Low Bromide (Br)/Chloride (Cl) and Potassium (K) /Cl ratios, high Sodium (Na) /Cl ratios, trace Magnesium (Mg) concentrations, and low Strontium (Sr) 87/Sr86 in brackish waters from the BRAS are inconsistent with in situ saline water from marine formation fluids of similar age. The ratios are consistent with in situ saline-water …
Early Permian Seawater From The Delta18o Record Of Fossil Bivalves: Seasonality And A Latitudinal Gradient, James Andrew Beard
Early Permian Seawater From The Delta18o Record Of Fossil Bivalves: Seasonality And A Latitudinal Gradient, James Andrew Beard
Earth & Environmental Sciences - Theses
The transition from a glaciated world to one that was ice-free makes the early Permian a time interval that in many ways mirrors the present, and hence there is great interest in constraining paleoclimate conditions over that transition. A common method for estimating ancient temperatures uses the oxygen isotope composition of marine carbonate, but this approach becomes significantly more complicated prior to the Cretaceous due to uncertainties about diagenesis and the isotopic composition of seawater, which has been hypothesized to be more depleted than during the Cenozoic. I use stable isotope compositions of sequentially microsampled accretionary calcite from fossil bivalves …
Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge
Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities.
Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such …
Assessing Eolian Dust Inputs To Soils In Dry Creek Experimental Watershed, Sw Idaho, Brian Jameson Stark
Assessing Eolian Dust Inputs To Soils In Dry Creek Experimental Watershed, Sw Idaho, Brian Jameson Stark
Boise State University Theses and Dissertations
A geochemical investigation of upland soils in the Dry Creek Experimental Watershed (DCEW) near Boise, Idaho was conducted to assess the potential contributions of eolian dust. Major and trace element compositions of soils within the watershed, loess deposits in the adjacent Western Snake River Plain (WSRP), and underlying granodiorite bedrock were evaluated. Multiple lines of evidence suggest a significant contribution of dust in the soils. Plots of Co/Ti, V/Ti and Cr/Ti indicate that the loess and bedrock occupy distinctly different compositional spaces and that the soils are of intermediate composition, suggesting that the soils are a mixture of the loess …
Geochemical Constraints On Groundwater Recharge In The Royal Slope Area, Grant County, Washington, Zoe Danielle Weis
Geochemical Constraints On Groundwater Recharge In The Royal Slope Area, Grant County, Washington, Zoe Danielle Weis
All Master's Theses
Groundwater, the primary source for potable water in the Columbia Plateau, has experienced significant declines over the past 25 years. Groundwater geochemistry and multivariable statistics were employed to identify and characterize the hydrofacies present, constrain recharge sources, and assess mixing of groundwater in the Royal Slope area of the Columbia Plateau. Geochemical analyses for major ions, stable isotopes, and radiogenic isotopes (14C and tritium) for age dating were performed on groundwater samples collected in 2010 from 24 wells in the study area. The results confirmed that the groundwater evolution in the study area follows the typical Columbia River Basalt Group …
Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler
Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler
UNLV Theses, Dissertations, Professional Papers, and Capstones
The most recent volcanism in the Valles caldera is represented by the El Cajete Pyroclastic Beds (ECPB), Battleship Rock Ignimbrite (BRI), and Banco Bonito Flow (BBF) as well as the VC-1 rhyolite, which are collectively known as the East Fork Member (EFM) of the Valles Rhyolite. The EFM was erupted at approximately 55 ka and 40 ka after an approximate 460 ka lull in volcanism. Previous studies suggested a mafic intrusion at depth triggered the eruptions. This thesis represents the first detailed study of the EFM.
Crystal assemblages consist of plagioclase, biotite, clinopyroxene, orthopyroxene, amphibole, sanidine, quartz, and oxides. Electron …
Glacial Shortcut Of Arctic Sea-Ice Transport, Michael Stärz, Xun Gong, Rüdiger Stein, Dennis A. Darby, Frank Kauker, Gerrit Lohmann
Glacial Shortcut Of Arctic Sea-Ice Transport, Michael Stärz, Xun Gong, Rüdiger Stein, Dennis A. Darby, Frank Kauker, Gerrit Lohmann
OES Faculty Publications
Due to the lack of data, the extent, thickness and drift patterns of sea ice and icebergs in the glacial Arctic remains poorly constrained. Earlier studies are contradictory proposing either a cessation of the marine cryosphere or an ice drift system operating like present-day. Here we examine the marine Arctic cryosphere during the Last Glacial Maximum (LGM) using a high-resolution, regional ocean-sea ice model. Whereas modern sea ice in the western Arctic Basin can circulate in the Beaufort Gyre for decades, our model studies present an extreme shortcut of glacial ice drift. In more detail, our results show a clockwise …
Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery
Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery
UNLV Theses, Dissertations, Professional Papers, and Capstones
The southern Quinn Canyon Range lies in an area of the Great Basin subjected to large-volume Oligocene-Miocene silicic volcanism and smaller volume basaltic volcanism during the Pliocene. Three major ash-flow tuff units were correlated in the southern Quinn Canyon Range (the Pahranagat Tuff, Clifford Spring Tuff, and the Cow Canyon Tuff) with regional units by utilizing U/Pb and 40 Ar/ 39Ar geochronology, geochemical correlation, and field mapping. Isotopic analysis suggests that basalt in the southern Quinn Canyon Range is part of the Death Valley-Pancake Range Basalt Zone and is similar to Reveille Range Episode 1 and 2 basalts. Further comparison …
Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology
Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology
Earth, Environmental, and Atmospheric Sciences Publications
No abstract provided.
Investigating The Utility Of Detrital Mineral Microchemistry And Radiogenic Isotope Compositions As Provenance Discriminators, Jack Hietpas
Investigating The Utility Of Detrital Mineral Microchemistry And Radiogenic Isotope Compositions As Provenance Discriminators, Jack Hietpas
Earth & Environmental Sciences - Dissertations
The provenance of clastic sediments remains one of the key tools for understanding the complex dynamic history of the Earth. Detritus shed from ancient orogens may be the only evidence available for determining the timing, evolution, paleogeography, and existence of tectonic events active over the 4.56 Ga of Earth history. The focus of this dissertation research is to assess the strengths and limitations of existing, as well as novel, tools for determining the provenance of siliciclastic sediments.
The utility of detrital monazite crystallization ages was investigated as a provenance indicator in both modern and ancient sedimentary systems. The results from …