Physical Sciences and Mathematics Commons^™

Snapshots Of Coastal Ecology During Glacial And Deglacial Intervals: A Multiproxy Assessment Of Northern Gulf Of Mexico Sediment Cores, Kendall Emilie Brome

LSU Master's Theses

Terrestrial ecosystems along exposed continental shelves during times of relatively low sea level and glaciation are rarely preserved due to the mechanically erosive nature of marine transgression and regression. In this study, I investigate the geochemical and palynological characteristics of two well-preserved sites in the northern Gulf of Mexico (NGOM) to determine the ecologic settings and subsequent mechanisms of preservation in this region. Both sites contain preserved terrigenous sediments of previously exposed coastal margins; the first is located at the Alabama Underwater Forest (~13 km south of Gulf Shores, AL, at ~15 mbsl), and optically stimulated luminescence dates to 72–56 …

Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon

LSU Master's Theses

The Upper Pennsylvanian (323.2–289.9 Ma) and Lower Permian (289.9-251 Ma), (Wolfcamp and Spraberry formations) interval of the Midland Basin, West Texas, contains a mixed succession of shale, carbonate, and siltstone/sandstone lithofacies that accumulated in a deep-water marine environment under variable hydrographic restrictions. The heterogenous stratigraphy found in the Wolfcamp and Spraberry formation was formed in response to variations in sea level and a transition from a glacial to an interglacial climate during the Early Permian. These fluctuations left behind alternating beds of mudstone and carbonate, interwoven with thin sandstone beds. Because the Wolfcamp and Spraberry formations are highly heterolithic, it …

Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon

LSU Master's Theses

The Upper Pennsylvanian (323.2–289.9 Ma) and Lower Permian (289.9-251 Ma), (Wolfcamp and Spraberry formations) interval of the Midland Basin, West Texas, contains a mixed succession of shale, carbonate, and siltstone/sandstone lithofacies that accumulated in a deep-water marine environment under variable hydrographic restrictions. The heterogenous stratigraphy found in the Wolfcamp and Spraberry formation was formed in response to variations in sea level and a transition from a glacial to an interglacial climate during the Early Permian. These fluctuations left behind alternating beds of mudstone and carbonate, interwoven with thin sandstone beds. Because the Wolfcamp and Spraberry formations are highly heterolithic, it …

Climate Change Risk To Coastal Airfield Stormwater Systems, Jedidiah R. Langlois

Theses and Dissertations

Climate change is resulting in rising sea levels and increased rainfall, posing new challenges to stormwater management, particularly along coastlines. The airfield stormwater systems of Tyndall Air Force Base discharge directly into an interior bay of the Gulf of Mexico through tidal canals and ditches, creating a risk of system inundation from high tidewater conditions from sea-level rise (SLR). This study explores the performance and consequences of an inundated stormwater system from SLR during rainfall events using the EPA’s Stormwater Management Model (SWMM). One hundred and fifty-three combinations of SLR and return year storms were applied to a model of …

Towards An Integrated Assessment Of Sea-Level Observations Along The U.S. Atlantic Coast, Brett A. Buzzanga

OES Theses and Dissertations

Sea levels are rising globally due to anthropogenic climate change. However, local sea levels that impact coastal ecosystems often differ from the global trend, sometimes by a factor of two or more. Improved understanding of this regional variability provides insights into geophysical processes and has implications for coastal communities developing resilience to ongoing sea-level rise. This dissertation conducts an investigation of sea level and its contributing processes at multiple spatial scales. Focusing on primarily interannual time-scales and data-driven approaches, new data sources and technologies are utilized to reduce current uncertainties.

First, sea-level trends are assessed over the global ocean and …

Understanding The Effect Of Internal Climate Variability On 20th Century Indian Ocean Sea Level: Results From Newly Reconstructed Sea Level Data, Praveen Kumar

OES Theses and Dissertations

Densely populated low-lying coastal zones of countries that border the Indian Ocean are at risk due to sea level rise. However, sea level change in the Indian Ocean is poorly understood primarily due to short and sparse tide gauge observations. Although satellite altimetry provides accurate basin-wide sea level measurements, trends computed from its relatively short (~27-year) data record are heavily influenced by interannual to multi-decadal variability. To accurately project future Indian Ocean sea level trends using altimeter data it is imperative that trends associated with fluctuating internal variability (interannual-decadal) be identified and extracted, which in turn requires long (~100-year) data. …

Long Term Changes To The Lower Columbia River Estuary (Lcre) Hydrodynamics And Salinity Patterns, Aqeel Al-Bahadily

Dissertations and Theses

Changing the morphological and hydrological conditions of an estuary can affect the estuarine hydrodynamics. The hydrograph of the Lower Columbia River Estuary (LCRE) and its bathymetry have been altered significantly over the past 150 years, such that the spring-freshet has decreased by 40-50% while winter flow has increased by 50%. In addition, the inlet width has been narrowed from 9.7 to 3.2km by the construction of jetties, and the controlling depth of the navigation channel has been deepened from 6 to 13m by continuous dredging. Also, ~70% of the shallow water habitat has been lost due to diking and wetland …

The Role Of The Southern Ocean On Global Ocean Circulation And Climate, Brady Scott Ferster

Theses and Dissertations

The Southern Ocean (SO) is a unique and highly dynamic region with strong temperature and salinity gradients. A comparison between satellite-derived salinity and observations indicates strong differences along coastal boundaries, areas of low temperature, and regions of strong currents. Although differences throughout much of the SO are shown to be negligible, resolution and smoothing in the products create large biases in horizontal gradients and errors in estimating the water cycle. The three-dimensional movement of water within the SO plays an important role in the global Meridional Overturning Circulation (MOC), where the Southern Hemisphere westerlies drive both zonal and meridional transports …

Reconstructing Barrier Island Behavior From Overstepped Deposits And Relict Onshore Morphology : Modeling And Field Approaches, Daniel James Ciarletta

Theses, Dissertations and Culminating Projects

Barrier Islands comprise 10% of the Earth’s shorelines, fringing every continent except Antarctica. Despite their ubiquity, much about the medium to long-term evolution of these coastal systems remain poorly understood, mostly due to the destruction of the geologic record as barriers migrate landward under the influence of rising sea level. Even where modern barriers and related strandplain systems have prograded and regressed, leaving evidence of their former geometries in the form of relict shorelines, field investigations often require intensive labor and time commitments to interpret past evolution. In this work, several investigations are undertaken to use novel numerical modeling techniques …

Studies Of The Long-Term Change Of Global Mean And Regional Sea Surface Height, Yingli Zhu

USF Tampa Graduate Theses and Dissertations

Sea level change could have profound impacts on our society. We report here on three related sea level change problems. First, a variety of regression models have predicted different rates for global mean sea level rise over the past century. Some of these models are accelerating and others are not. We ask whether we can distinguish between these using a new nonparametric noise model that we have developed. Simulations show that we can, and further imply that GMSL is rising at an accelerating rate. Second, historical global mean sea level is reconstructed from tide gauges that are located along coastlines …

Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller

USF Tampa Graduate Theses and Dissertations

The aim of paleoenvironmental studies is to reconstruct characteristics of the past environment from fossil assemblages preserved in sedimentary strata. Thus, studies of modern surface assemblages, quantitatively correlated to the environmental parameters, are required before reliable interpretations can be made. For this dissertation, two different techniques were applied in two case studies: a reconstruction making use of a benthic foraminiferal transfer function from the intertidal marshes in the eastern Mississippi Sound, Alabama/Mississippi, and a qualitative reconstruction of ocean current activity on the Western Australian shelf.

Modern salt-marsh foraminifera were collected from Grand Bay, Pascagoula, Fowl River, and Dauphin Island across …

Build-And-Fill Development Of Lower Ismay (Middle Pennsylvanian Paradox Formation) Phylloid-Algal Mounds Of The Paradox Basin, Southeastern Utah, Lincoln H. Reed

Theses and Dissertations

Phylloid-algal mounds form heterogeneous hydrocarbon reservoirs in the southeastern portion (Blanding sub-basin) of the Paradox Basin. Well-studied Lower Ismay mounds exposed along walls of the San Juan River gorge in the vicinity of Eight Foot Rapids, the west limb of the Raplee Anticline, and at the classic Honaker Trail locality (southwestern Paradox Basin) have often been cited as outcrop analogs of productive subsurface mounds. Until now, however, there has not been a complete description of the distribution, size, and spacing of outcropping algal mounds at the classic Eight Foot Rapids locality. The Lower Ismay sequence was analyzed in the context …

Sea Surface Height: A Versatile Climate Variable For Investigations Of Decadal Change, Philip Robert Thompson

USF Tampa Graduate Theses and Dissertations

Decadal variations in climate are important, because the magnitude of sustained decadal change is often much larger than the often discussed background trends. Climate variability at interannual and longer periods is most often discussed in the context of climate modes defined by sea level pressure (SLP) and sea surface temperature (SST) patterns. However, SLP and SST are not capable descriptors of ocean dynamics. The approximately two decades of global sea surface height (SSH) measurements from satellite altimetry reveal substantial low-frequency redistributions of heat and salt in the ocean, which may or may not be related to defined climate modes. In …

Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson

LSU Master's Theses

Site 380 of the Deep Sea Drilling Program [DSDP] is located in the southwestern region of the Black Sea (42°05.94’, 29°36.82’E). The location of this site is important due to its proximity to the narrow Bosphorus strait, the only present-day connection between the Black Sea and the Aegean Sea. Drops in eustatic sea level during extensive Pleistocene glacial episodes disconnected the Black Sea from the Aegean Sea at the Bosphorus strait, creating a change from brackish to freshwater within the Black Sea during these intervals. Organic-walled phytoplankton (dinoflagellate cysts, acritarchs, and fresh-water algae) are investigated to better constrain these glacio-eustatic …

Outlet Glacier Dynamics In East Greenland And East Antarctica, Leigh Asher Stearns

Electronic Theses and Dissertations

Ice mass from the interior of Greenland and Antarctica is transported to the ocean by numerous large, fast-flowing outlet glaciers. Changes in the flow configuration of these outlet glaciers modulate ice sheet mass balance and sea level. Several recent studies have highlighted rapid increases in glacier speed in both Greenland and Antarctica, implying that the near-term contribution to sea level from ice sheets is under-estimated by current models. Here, the mass balance and force budget of several large outlet glaciers in East Greenland and East Antarctica are investigated using remote-sensing and field-based measurements. Recent estimates show that Greenland’s contribution to …

Correlating Late Pleistocene Deposits On The Coastal Plain Of Virginia With The Glacial-Eustatic Sea-Level Curve, Timothy Wullschleger Scott

OES Theses and Dissertations

Late Pleistocene sediments mapped along Virginia's southeastern coastal plain record deposition by high-frequency cycles during isotope stages 5 to 1. Correlations between several geologic units both south (S) and east (E) of the Chesapeake Bay have proven difficult due to insufficient dating methods. To improve these regional correlations, two members of the Tabb Formation on Virginia's southside and two formations on the southern Delmarva Peninsula were selected for stratigraphic analyses. Ground penetrating radar provided geologic details in areas where samples were collected for optically stimulated luminescence (OSL) dating. The stratigraphically older units, Sedgefield Member of the Tabb Formation (S) and …

Establising A High-Frequency Standard Reference Sequence Stratigraphy, Sea-Level Curve, And Biostratigraphy For Morrowan Strata Of The Lower Absaroka I Time Slice Based Upon The Bird Spring Formation, Arrow Canyon, Nevada, Kristen Phelps Briggs

Theses and Dissertations

For the same reasons which prompted its ratification in 1990 as the Global Stratotype Section and Point for the Mid-Carboniferous boundary, namely, section completeness, abundant fossils, and excellent exposure, the Morrowan Arrow Canyon Bird Spring strata is recommended as a candidate standard sequence stratigraphic reference for the Morrowan portion of the Lower Absaroka I supersequence. The stratigraphic architecture of Morrowan strata in Arrow Canyon was largely controlled by high-amplitude (100-m), high-frequency sea-level changes. Outcrop data and facies stacking patterns define 59 fifth-order fundamental cycles. These fundamental cycles stack into ten third-order sequences with an average duration of 320 ka. Changes …

Sea Level Slopes And Volume Fluxes Produced By Atmosphere Forcing In Chesapeake Bay, David Salas Monreal

OES Theses and Dissertations

Year long time series at eight stations in the Chesapeake Bay and inner shelf were used to determine the relative influence of wind, barometric pressure and thermosteric effects on subtidal sea level variability and slopes. Special emphasis was placed on the lower Chesapeake Bay, where inverse barometric effects accounted for up to 33% of the subtidal sea level variations and thermosteric effects accounted for less than 1 % of the variations. The greatest thermosteric influence was noted at the southernmost, saltier and shallower location (Chesapeake Bay Bridge Tunnel). Wind forcing accounted for most of this station's variability, making up more …

Morphostatic Long-Term Hypsometric Analysis Of Coastal Bay Environments: Hog Island Bay, Virginia, Kathleen Marie Overman

OES Theses and Dissertations

Sea level has been rising at a variable rate since the end of the last glaciation approximately 18,000 years ago. As the transgressing sea inundates the shore areas a series of landform state changes occur in coastal regions. One such change of state in a coastal paleo-river channel is from an estuary into a coastal lagoon. At large temporal intervals (thousands of years) the hypsometry of a coastal lagoon varies as a result of sea level rise due to these changes of state. Using a morphostatic technique, the time period in which an estuary transforms into a coastal lagoon can …