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Articles 22201 - 22230 of 29955

Full-Text Articles in Geology

Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak Dec 2017

Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak

Theses and Dissertations

Craters formed by impact and volcanic processes are among the most fundamental planetary landforms. This study examines the morphology of diverse craterforms on Io, the Moon, Mars, and Earth using quantitative, outline-based shape analysis and multivariate statistical methods to evaluate the differences between different types of. Ultimately, this should help establish relationships between the form and origin of craterforms. Developed in the field of geometric morphometrics by paleontological and biological sciences communities, these methods were used for the analysis of the shapes of crater outlines. The shapes of terrestrial ash-flow calderas, terrestrial basaltic shield calderas, martian calderas, Ionian paterae, and …


Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu Dec 2017

Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The 410 and 660 km discontinuities (d410 and d660, respectively) beneath Alaska and adjacent areas are imaged by stacking 75,296 radial receiver functions recorded by 438 broadband seismic stations with up to 30 years of recording period. When the 1-D IASP91 Earth model is used for moveout correction and time depth conversion, significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of the d410 and d660 for the entire study area is 417 ± 12 km and 665 ± 12 km, respectively, and the mean mantle transition zone (MTZ) …


Aquifers Of Nebraska Ii: The Niobrara Aquifer, Dana Divine, Robert Matthew Joeckel, Sue Olafsen Lackey Dec 2017

Aquifers Of Nebraska Ii: The Niobrara Aquifer, Dana Divine, Robert Matthew Joeckel, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

The marine shale, chalk, marl, and chalky limestone of the Niobrara Formation directly underlie Quaternary sediments in 23 counties from south-central to northeastern Nebraska. Nevertheless, the formation serves as an aquifer only in and around Cedar, Madison, and Nuckolls counties. Niobrara aquifer wells mostly supply irrigation, domestic, and livestock needs. Two hundred of the approximately 230 active registered wells in Nebraska that are screened entirely in the Niobrara aquifer are in Cedar County and environs. About another 200 wells in this area are screened in both the Niobrara aquifer and overlying Quaternary sediments. Wells screened entirely in the Niobrara aquifer …


The Utility Of Foraminifera In Documenting Sediment Provenance For Overwash Deposits: A Case Study Using Sediments Deposited By Tropical Cyclone Pam In Vanuatu, Thomas Kosciuch Dec 2017

The Utility Of Foraminifera In Documenting Sediment Provenance For Overwash Deposits: A Case Study Using Sediments Deposited By Tropical Cyclone Pam In Vanuatu, Thomas Kosciuch

Master's Theses

Tropical cyclone inundation is a major threat to the highly exposed islands of the South Pacific. This vulnerability was highlighted in March 2015 when Tropical Cyclone (TC) Pam made landfall on Vanuatu as a Category 5 storm, impacting coastlines with storm surges that produced high water marks up to 7 m above MSL and deposited sediments up to 400 m inland. We examined the foraminiferal assemblages contained within TC Pam sediments at two locations in Vanuatu: a mixed-carbonate embayment (Manuro), and a volcaniclastic beach (Port Resolution Bay; PRB). At Manuro, the TC Pam sediments were up to 10 cm thick …


Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts Dec 2017

Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts

Theses and Dissertations

Snowmelt river systems exhibit seasonal fluxes in water chemistry, potentially affecting the water supply of one-sixth of the worlds population. In this study, we examined water chemistry of the upper Provo River, northern Utah, which supplies water to over two million people along the urban Wasatch Front. Seasonal changes in water chemistry were characterized by analyzing discharge and dissolved organic carbon (DOC) with dissolved trace metal and cation concentrations (La, Pb, Cu, Al, Be, Sr and K) over three consecutive water years 20142016, with intensive sampling during snowmelt runoff. To better understand links between metal movement and DOC, we sampled …


Geological Characterization Of Precambrian Nonconformities: Implications For Injection-Induced Seismicity In The Midcontinent United States, Laura Cuccio Dec 2017

Geological Characterization Of Precambrian Nonconformities: Implications For Injection-Induced Seismicity In The Midcontinent United States, Laura Cuccio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The midcontinent United States, a region which typically does not experience many earthquakes, has experienced a significant increase in the number of earthquakes over the last decade. This increase in earthquake activity has been linked to wastewater injection, a process in which large volumes of wastewater from oil and gas extraction are injected into deep (2-3 km), high-permeability sedimentary rocks, near low-permeability Precambrian (>540-million-year-old) crystalline ‘basement’ rocks. The contact between these two rock types is referred to as the Precambrian nonconformity. Injection-induced earthquakes occur on or near basement-hosted faults due to an increase in pore fluid pressures, which implies …


Usarray Imaging Of North American Continental Crust, Xiaofei Ma Dec 2017

Usarray Imaging Of North American Continental Crust, Xiaofei Ma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The layered structure and bulk composition of continental crust contains important clues about its history of mountain-building, about its magmatic evolution, and about dynamical processes that continue to happen now. Geophysical and geological features such as gravity anomalies, surface topography, lithospheric strength and the deformation that drives the earthquake cycle are all directly related to deep crustal chemistry and the movement of materials through the crust that alter that chemistry.

The North American continental crust records billions of years of history of tectonic and dynamical changes. The western U.S. is currently experiencing a diverse array of dynamical processes including modification …


Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck Dec 2017

Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck

Theses and Dissertations

The Lone Star porphyry copper deposit in the Safford District of southeastern Arizona was discovered in the late 1800's but never mined on a large scale. In addition to typical copper oxide species such as chrysocolla, the upper part of the deposit has zones of mineralization in which the chemical assays of core samples have higher amounts of copper than can be visually assigned to the observed copper-bearing minerals. The goal of this study is to identify the Cu-bearing minerals, which is crucial because the efficiency of the extraction processes is strongly dependent upon the mineralogy. Samples from seven cores …


Paleozoic Sandstones In The Tri-State Region, Southern Ozarks: Tectono-Stratigraphic Sequence Development And Compositional Evolution, The Source And Delivery Conundrum, And The Regional Tectonic History, Elvis Chekwube Bello Dec 2017

Paleozoic Sandstones In The Tri-State Region, Southern Ozarks: Tectono-Stratigraphic Sequence Development And Compositional Evolution, The Source And Delivery Conundrum, And The Regional Tectonic History, Elvis Chekwube Bello

Graduate Theses and Dissertations

The Paleozoic stratigraphic record of the Ozark Region, southern midcontinent has been divided into at least 33 formations, with the most significant thickness of 9692 feet preserved in northwest Arkansas. The potential thickness would have been much greater, but epeirogenic movements and sea-level rise and fall produced regional surfaces of erosion reducing the record. That interplay between tectonics (epeirogenic movements) and eustatic change (transgressive-regressive cycles) preserved in the Ozark sedimentary history provides the basis for recognition of five distinct, but related, tectonostratigraphic units designated TS 1 through TS 5: Late Precambrian-Middle Cambrian (TS 1), Late Cambrian-Earliest Ordovician (TS 2), Early …


3d Seismic Interpretation Of A Plio-Pleistocene Mass Transport Deposit In The Deepwater Taranaki Basin Of New Zealand, Francisco Jose Rusconi Dec 2017

3d Seismic Interpretation Of A Plio-Pleistocene Mass Transport Deposit In The Deepwater Taranaki Basin Of New Zealand, Francisco Jose Rusconi

Graduate Theses and Dissertations

A series of Plio-Pleistocene mass transport deposits (MTD) have been identified in the deepwater Taranaki Basin, in New Zealand, using the Romney 3D seismic survey, which covers an area of approximately 2000 km2. One of these MTDs has been chosen for description and interpretation based on high confidence mapping of its boundary surfaces. The deposit exhibits an array of interesting features similar to those documented by researchers elsewhere plus a unique basal feature unlike those previously observed. The basal shear surface exhibits erosional features such as grooves, “monkey fingers”, and glide tracks. Internally, the MTD is typically characterized by low …


An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman Dec 2017

An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman

Dissertations

Deformational features such as subsidence, sinkholes, fissures, settling and cracks in buildings and structures, and earthquakes are being reported from many of the world’s arid lands, in areas where fossil aquifers are being excessively exploited. Using the Lower Mega Aquifer System (LMAS) in Arabia as a test site, I applied an integrated approach (remote sensing, geodesy, GIS, geology, hydrogeology, and geotechnical) to identify nature, intensity, spatial distribution, and factors controlling the observed deformation in the central (Al-Qassim and Ha'il regions; area: 16×10⁴ km²) and the northern (Wadi As-Sirhan Basin; area: ~10.9×10⁴ km²) Arabia. A four -fold approach was adopted to …


A Geochemical Investigation And Comparison Between Organic-Rich Black Shales And Mississippi Valley-Type Pb-Zn Ores In The Southern Ozarks Region, Bryan Michael Bottoms Dec 2017

A Geochemical Investigation And Comparison Between Organic-Rich Black Shales And Mississippi Valley-Type Pb-Zn Ores In The Southern Ozarks Region, Bryan Michael Bottoms

Graduate Theses and Dissertations

Mississippi Valley-type (MVT) deposits are base metal sulfide deposits that are important economic sources of both Pb and Zn, accounting for 24% of the global Pb and Zn reserves. They are found all over the world, often hosted in platform carbonates on the flanks of sedimentary basins, and often in proximity to hydrocarbons. They are epigenetic, not related to igneous activity, and thought to be sourced from low temperature, highly saline basinal brines that are expelled from sedimentary basins during compaction and/or in conjunction with an orogenic event. The basinal lithologies responsible for providing the metals for the ores are …


De Paepe, Duane - Collector (Mss 625), Manuscripts & Folklife Archives Nov 2017

De Paepe, Duane - Collector (Mss 625), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid only for Manuscripts Collection 625. The Duane De Paepe Kentucky Cave Saltpetre History Research Collection, a collection of historical research, field notes, cave surveys, photographs, maps, reports, and scholarly writing on saltpetre mining in Kentucky, especially at Mammoth Cave. The collection was created under a research program sponsored by the Cave Research Foundation and the National Geographic Society in Kentucky, 1976-1980, and directed by De Paepe.


A Geophysical Investigation Of Stratigraphy And Structure On St. Catherines Island, Georgia, Anne M. Delua Nov 2017

A Geophysical Investigation Of Stratigraphy And Structure On St. Catherines Island, Georgia, Anne M. Delua

Honors College Theses

Geophysical tools were used to investigate potential structural and stratigraphic pathways of the salt water intrusion that is affecting the surficial aquifer on St. Catherines Island, Georgia. Ground penetrating radar (GPR) is a geophysical tool that uses electromagnetic waves to view the subsurface. GPR is used for a variety of applications stratigraphically, biologically, and anthropogenically. GPR electromagnetic waves react to changes in density and composition and type and percentage of pore fluids in sediment and rock. GPR waves also react to interfaces including fractures and faults. GPR waves exhibit attenuation and decreased return signal in materials such as clay. Fresh …


Investigation Of Sediment Ridges Using Bathymetry And Backscatter Near Clearwater, Florida, Lewis Stewart Nov 2017

Investigation Of Sediment Ridges Using Bathymetry And Backscatter Near Clearwater, Florida, Lewis Stewart

USF Tampa Graduate Theses and Dissertations

Changes in sediment morphology on the West Florida Shelf is investigated over a 14-year time period using multibeam bathymetry and backscatter in water depths between 10 m and 20 m, off the coast of Indian Rocks Beach, Pinellas County, Florida. Bathymetric surveys collected in 2002 (Kongsberg EM 3000 at 300 kHz) and 2016 (Reson 7125 at 400 kHz) were processed using CARIS Hips and Sips to create bathymetric maps and backscatter images. These data were then interpreted and compared in order to test hypotheses and answer questions related to sediment migration and sediment volume change.

The following questions prompted this …


A Prograding Margin During Global Sea-Level Maxima: An Example From Mahajanga Basin, Northwest Madagascar, Jonathan Obrist-Farner, Philip J. Ball, Thomas A. (Mac) Mcgilvery, Raymond R. Rogers Nov 2017

A Prograding Margin During Global Sea-Level Maxima: An Example From Mahajanga Basin, Northwest Madagascar, Jonathan Obrist-Farner, Philip J. Ball, Thomas A. (Mac) Mcgilvery, Raymond R. Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Mesozoic shelf margin in the Mahajanga Basin, northwest Madagascar, provides an example where inherited palaeobathymetry, coupled with sea-level changes, high sediment supply and fluctuations in accommodation influenced the stacking patterns and geometry of clinoforms that accreted onto a passive rifted margin. Two-dimensional (2D) seismic profiles are integrated with existing field data and geological maps to study the evolution of the margin. The basin contains complete records of transgression, highstand, regression and lowstand phases that took place from Jurassic to Cretaceous. Of particular interest is the Cretaceous, Albian to Turonian (ca. 113-93 Ma), siliciclastic shelf margin that prograded …


Snow Accumulation Variability Over The West Antarctic Ice Sheet Since 1900: A Comparison Of Ice Core Records With Era‐20c Reanalysis, Yetang Wang, Elizabeth R. Thomas, Shugui Hou, Baojuan Huai, Shuang-Ye Wu, Weijun Sun, Shanzhong Qi, Minghu Ding, Yulun Zhang Nov 2017

Snow Accumulation Variability Over The West Antarctic Ice Sheet Since 1900: A Comparison Of Ice Core Records With Era‐20c Reanalysis, Yetang Wang, Elizabeth R. Thomas, Shugui Hou, Baojuan Huai, Shuang-Ye Wu, Weijun Sun, Shanzhong Qi, Minghu Ding, Yulun Zhang

Department of Earth, Environment and Sustainability Faculty Publications

This study uses a set of 37 firn core records over the West Antarctic Ice Sheet (WAIS) to test the performance of the twentieth century from the European Centre for Medium‐Range Weather Forecasts (ERA‐20C) reanalysis for snow accumulation and quantify temporal variability in snow accumulation since 1900. The firn cores are allocated to four geographical areas demarcated by drainage divides (i.e., Antarctic Peninsula (AP), western WAIS, central WAIS, and eastern WAIS) to calculate stacked records of regional snow accumulation. Our results show that the interannual variability in ERA‐20C precipitation minus evaporation (P − E) agrees well with the corresponding ice …


Lower–Middle Pennsylvanian Strata In The North American Midcontinent Record The Interplay Between Erosional Unroofing Of The Appalachians And Eustatic Sea-Level Rise, J.K. Kissock, E. S. Finzel, D. H. Malone, J. P. Craddock Nov 2017

Lower–Middle Pennsylvanian Strata In The North American Midcontinent Record The Interplay Between Erosional Unroofing Of The Appalachians And Eustatic Sea-Level Rise, J.K. Kissock, E. S. Finzel, D. H. Malone, J. P. Craddock

Faculty Publications - Geography, Geology, and the Environment

Morrowan, Atokan, and Desmoinesian (Lower–Middle Pennsylvanian) clastic strata in the Forest City (Iowa, northwest Missouri, eastern Nebraska, and Kansas) and Illinois Basins on the North American midcontinent record the interaction between fluctuations in eustatic sea-level and major tectonic events. One of three major Paleozoic eustatic sea-level lows occurred near the Mississippian/Pennsylvanian boundary and was followed by a eustatic rise that continued into Late Pennsylvanian time. Alleghenian mountain building that is linked to the creation of the Pangean supercontinent also began during latest Mississippian time and continued until latest Pennsylvanian or earliest Permian time. Detrital-zircon geochronology and stratigraphic descriptions allow reconstruction …


U–Pb Dating Of Cave Spar: A New Shallow Crust Landscape Evolution Tool, D. D. Decker, V. J. Ployak, Y. Asmeron, Matthew Lachniet Nov 2017

U–Pb Dating Of Cave Spar: A New Shallow Crust Landscape Evolution Tool, D. D. Decker, V. J. Ployak, Y. Asmeron, Matthew Lachniet

Geoscience Faculty Research

In carbonate terranes, rocks types that provide apatite are not available to effectively use apatite fission track (AFT) or (U/Th)‐He chronometry (AHe). Here we suggest that calcite cave spar can be an effective chronometer and complimentary to AFT and AHe thermochronometers in carbonate regions such as our study area, the Guadalupe Mountains of southeastern New Mexico, and west Texas. Our measured depth of cave spar deposition is 500 ± 250 m beneath the regional water table, formed at temperatures of 40° to 80°C, indicating that these caves and their spar crystals form near the supercritical CO2‐subcritical CO2 boundary where we …


Assemblage Of The Emergent Plantation Museum Experience, Amy E. Potter, Candace Bright, Derek H. Alderman, David L. Butler, Perry L. Carter, Stephen P. Hanna, E. Arnold Modlin Nov 2017

Assemblage Of The Emergent Plantation Museum Experience, Amy E. Potter, Candace Bright, Derek H. Alderman, David L. Butler, Perry L. Carter, Stephen P. Hanna, E. Arnold Modlin

Earth, Environment & Sustainability: Faculty Presentations (1988-2022)

This presentation was given during the Southeastern Division of the Association of American Geographers Annual Meeting.


Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt Nov 2017

Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt

USF Tampa Graduate Theses and Dissertations

In order to determine the timing of Antarctic ice sheet retreat and advance during the Late Quaternary, various tools are used to measure the age of marginal marine sediments. Carbonate 14C dating is a well-established approach, but requires foraminiferal microfossils, shells or other carbonate materials that are rare in most Antarctic regions, and may also suffer from vital effects, which can result in variability of up to 500 years in living organisms. Bulk acid insoluble organic (AIO) 14C dates are frequently as an alternative, but this approach works best where high productivity and sedimentation rates reign, and not too well …


Quaternary Sea-Level History And The Origin Of The Northernmost Coastal Aeolianites In The Americas: Channel Islands National Park, California, Usa, Daniel R. Muhs, Jeffrey S. Pigati, R. Randall Schumann, Gary L. Skipp, Naomi Porat, Stephen B. Devogel Nov 2017

Quaternary Sea-Level History And The Origin Of The Northernmost Coastal Aeolianites In The Americas: Channel Islands National Park, California, Usa, Daniel R. Muhs, Jeffrey S. Pigati, R. Randall Schumann, Gary L. Skipp, Naomi Porat, Stephen B. Devogel

United States Geological Survey: Staff Publications

Along most of the Pacific Coast of North America, sand dunes are dominantly silicate-rich. On the California Channel Islands, however, dunes are carbonate-rich, due to high productivity offshore and a lack of dilution by silicate minerals. Older sands on the Channel Islands contain enough carbonate to be cemented into aeolianite. Several generations of carbonate aeolianites are present on the California Channel Islands and represent the northernmost Quaternary coastal aeolianites on the Pacific Coast of North America. The oldest aeolianites on the islands may date to the early Pleistocene and thus far have only been found on Santa Cruz Island. Aeolianites …


Late Quaternary Uplift Along The North America-Caribbean Plate Boundary: Evidence From The Sea Level Record Of Guantanamo Bay, Cuba, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons, Robert B. Halley Nov 2017

Late Quaternary Uplift Along The North America-Caribbean Plate Boundary: Evidence From The Sea Level Record Of Guantanamo Bay, Cuba, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons, Robert B. Halley

United States Geological Survey: Staff Publications

The tectonic setting of the North America-Caribbean plate boundary has been studied intensively, but some aspects are still poorly understood, particularly along the Oriente fault zone. Guantanamo Bay, southern Cuba, is considered to be on a coastline that is under a transpressive tectonic regime along this zone, and is hypothesized to have a low uplift rate. We tested this by studying emergent reef terrace deposits around the bay. Reef elevations in the protected, inner part of the bay are ~11e12 m and outercoast, wave-cut benches are as high as ~14 m. Uranium-series analyses of corals yield ages ranging from ~133 …


Evidence Of Subglacial Brine Inflow And Wind-Induced Mixing From High Resolution Temperature Measurements In Lake Bonney, Antarctica, Jade Lawrence Nov 2017

Evidence Of Subglacial Brine Inflow And Wind-Induced Mixing From High Resolution Temperature Measurements In Lake Bonney, Antarctica, Jade Lawrence

LSU Master's Theses

Hypersaline brine beneath Taylor Glacier enters proglacial West Lobe Lake Bonney (WLB) subglacially as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the water column of WLB. Because of the extremely high salinities below the chemocline in WLB, density is determined almost entirely by salinity and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude in to the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. This study …


Combining Downhole And Sediment Logging To Understand Spatial Variability In Grain-Size, Facies, And Reservoir Quality Of A Large-Scale Mississippi River Point Bar, False River, Louisiana, Elizabeth D. Olson Nov 2017

Combining Downhole And Sediment Logging To Understand Spatial Variability In Grain-Size, Facies, And Reservoir Quality Of A Large-Scale Mississippi River Point Bar, False River, Louisiana, Elizabeth D. Olson

LSU Master's Theses

Although the general processes by which meandering river point bars are constructed have been known for some time, there is a lack of clarity regarding why small-scale heterogeneities develop. This is especially true in the largest meandering river systems, which are equivalent to some of the most important hydrocarbon reservoirs in the world. In this study, we evaluate the stratigraphic architecture of the 80 km2 False River Point Bar System on the Lower Mississippi River and use the knowledge gained to better comprehend point bar construction at different phases. Previous studies of small to medium-scale systems have been unable …


High Throughput Petrochronology And Sedimentary Provenance Analysis By Automated Phase Mapping And Laicpms, Pieter Vermeesch, Martin Rittner, Ethan Petrou, Jenny Omma, Chris Mattinson, Eduardo Garzanti Nov 2017

High Throughput Petrochronology And Sedimentary Provenance Analysis By Automated Phase Mapping And Laicpms, Pieter Vermeesch, Martin Rittner, Ethan Petrou, Jenny Omma, Chris Mattinson, Eduardo Garzanti

All Faculty Scholarship for the College of the Sciences

The first step in most geochronological studies is to extract dateable minerals from the host rock, which is time consuming, removes textural context, and increases the chance for sample cross contamination. We here present a new method to rapidly perform in situ analyses by coupling a fast scanning electron microscope (SEM) with Energy Dispersive X-ray Spectrometer (EDS) to a Laser Ablation Inductively Coupled Plasma Mass Spectrometer (LAICPMS) instrument. Given a polished hand specimen, a petrographic thin section, or a grain mount, Automated Phase Mapping (APM) by SEM/EDS produces chemical and mineralogical maps from which the X-Y coordinates of the datable …


Paleoenvironmental Variation And Provenance Records From Neogene Deep Sea Sediment Of The South China Sea, Chang Liu Nov 2017

Paleoenvironmental Variation And Provenance Records From Neogene Deep Sea Sediment Of The South China Sea, Chang Liu

LSU Doctoral Dissertations

I employed several paleoenvironmental proxies by utilizing deep sea sediment from the largest marginal basin in east Asia, namely the South China Sea (SCS), to reconstruct the long term paleoenvironmental variation in SE Asia since the Neogene. Sediments deposited within the SCS were mainly delivered by several major fluvial systems whose catchment basins cover several geological blocks in SE Asia. By analyzing the sediment’s geochemical and mineralogical characteristics, several indices which are affected by the source of the sedimentary influx, as well as the weathering state could be built and applied to constrain my paleoenvironmental reconstructions

Two deep sea drilling …


How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux Nov 2017

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …


Exploring The Historical Earthquakes Preceding The Giant 1960 Chile Earthquake In A Time-Dependent Seismogenic Zone, Marco Cisternas, Matias Carvajal, Robert Wesson, Lisa L. Ely, Nicolás Gorigoitia Nov 2017

Exploring The Historical Earthquakes Preceding The Giant 1960 Chile Earthquake In A Time-Dependent Seismogenic Zone, Marco Cisternas, Matias Carvajal, Robert Wesson, Lisa L. Ely, Nicolás Gorigoitia

All Faculty Scholarship for the College of the Sciences

New documentary findings and available paleoseismological evidence provide both new insights into the historical seismic sequence that ended with the giant 1960 south‐central Chile earthquake and relevant information about the region’s seismogenic zone. According to the few available written records, this region was previously struck by earthquakes of varying size in 1575, 1737, and 1837. We expanded the existing compilations of the effects of the two latter using unpublished first‐hand accounts found in archives in Chile, Peru, Spain, and New England. We further investigated their sources by comparing the newly unearthed historical data and available paleoseismological evidence with the effects …


Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives Nov 2017

Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid only for Manuscripts Collection 620. Correspondence, research notes, drafts, photographs, reference works and bibliographic material of Burton S. Faust relating to his studies of the chemical, historical and cultural aspects of saltpetre and of spelean saltpetre mining in the United States.