Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, 2016 University of Southern Mississippi
Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy
The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a ...
Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, 2016 University of Tennessee, Knoxville
Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll
This study tested whether transport distances (< 500 m) have the capacity to shape the geochemistry of sediments across multiple grain-size populations due to sorting derived from a single source. In the Stepladder Mountains, Mojave Desert, CA, a < 1 km2 [square kilometers] watershed allows for a controlled study to understand how modern sediments acquire their composition from a single granodioritic source in an arid climate where there is no chemical weathering. Sediments are naturally sorted into distinct grain-size populations, with modes ranging from very fine sand to gravel within a single, alluvial channel. Sediment samples representative of each population were petrographically and geochemically analyzed in order to test the effectiveness of commonly used discrimination diagrams. Sediments became proportionally enriched in plagioclase and biotite and depleted in K-feldspar and quartz with decreasing grain size ...
The Spatial Distribution And Origins Of Sandstone Monoliths In The Swauk Watershed, Kittitas County, Wa, Rebeca Becerra, Daniel O'Dell
Symposium Of University Research and Creative Expression (SOURCE)
Large groups of gigantic sandstone and conglomerate monoliths populate the Swauk Watershed of northern Kittitas County. These monoliths rest on side slopes in the watershed and distinctively project from their surroundings. The origins of these features are unknown. We studied these monoliths in the field by mapping their spatial distribution, describing their morphology and composition, and measuring their orientation and sizes in order to determine their origins. We used Google Earth and topographic maps to locate the monoliths and map their distribution. Interpretations were based from field work data and past research. Our field results show commonalities between the features ...
Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, 2016 Stephen F Austin State University
Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, Wesley L. Turner
Electronic Theses and Dissertations
Transitional sediments on carbonate ramp slopes act as a link to relatively well-studied platform and basin depositional environments. In the southern Midland Basin, the key to understanding the relationship between these environments lies in the allochthonous gravity flow sediments found on the slope. Here, a succession of various gravity flow deposits is used to interpret how base level fluctuations affect the type of deposits found on the slope and their effect on the deep basinal environment. This study utilizes core samples from the Wolfcamp Formation adjacent to the Central Basin Platform in five wells in Northwest Crockett County, Texas. The ...
Dating Late Quaternary Alluvial Fills In The Platte River Valley Using Optically Stimulated Luminescence Dating, 2016 University of Nebraska - Lincoln
Dating Late Quaternary Alluvial Fills In The Platte River Valley Using Optically Stimulated Luminescence Dating, Jacob C. Bruihler
Theses and Dissertations in Geography
Alluvial fills underlying the Platte River Valley in Nebraska record the geologic history of the Platte River in the late Quaternary. This study investigated the alluvium underlying the valley near the cities of North Platte and Kearney, Nebraska. Data obtained from sediment cores drilled in the alluvial deposits was used to investigate the changes in Platte River dynamics on a glacial – interglacial timescale. Optically Stimulated Luminescence (OSL) dating was used to determine burial ages of recovered sediments and to quantify the thicknesses of the late Pleistocene and Holocene alluvial fills at each study area. Our geochronology depicts considerable differences in ...
Systematic Patterning Of Sediments In French Polynesian Coral Reef Systems, 2016 Nova Southeastern University
Systematic Patterning Of Sediments In French Polynesian Coral Reef Systems, Andrew Calhoun
Theses and Dissertations
Through a discipline termed “comparative sedimentology”, modern carbonate depositional environments have been used extensively as analogs to aid in the interpretation of equivalent fossil systems. Using field samples, GIS and remote sensing data for three isolated carbonate platforms in the Pacific, this thesis seeks to examine relationships between grain texture and grain type and their environment of deposition. The motivation is to highlight relationships that have the potential to better understand facies relations on carbonate platforms, and thereby reduce uncertainty and increase accuracy of subsurface exploration. The results of this study show that on Raivavae, Tubuai, and Bora Bora: French ...
Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou
In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the ...
Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, 2016 University of Chinese Academy of Sciences
Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu
Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect ...
Correlation Of Basal Cambrian Sandstones Across North America, 2016 Cedarville University
Correlation Of Basal Cambrian Sandstones Across North America, Joshua W. Perez
The Research and Scholarship Symposium
A thin, widespread sequence of siliciclastic strata ranging from lower to upper Cambrian age overlies Precambrian crystalline and metamorphic basement rock bounded by the Great Unconformity. This sequence is mainly comprised of basal Cambrian sandstones which can be subdivided into three distinct suites of lithofacies transitioning in age across most of North America. From the west, which is most notable for the Tapeats sandstone of Arizona and Nevada, lies gravelly to boulder sized conglomerates directly overlying basement rock. Eastward, the lower to middle Cambrian consists of a variety of ledge-forming sandstones which contain various areas rich in cross bedded, as ...
Preliminary Correlation And Isopach Map Of Navajo-Aztec-Nugget Sandstones, Western United States, 2016 Cedarville University
Preliminary Correlation And Isopach Map Of Navajo-Aztec-Nugget Sandstones, Western United States, Emily Jackson
The Research and Scholarship Symposium
Lower and middle Jurassic sandstones across western North America were correlated using stratigraphic thickness and lithofacies data obtained from the AAPG-produced Correlation of Stratigraphic Units of North America (COSUNA) data charts and spreadsheets. An isopach map and a series of stratigraphic cross-sections were created to display the lateral and horizontal extent of the correlated formations. The goal was to determine lateral equivalents of the primarily lower Jurassic Navajo Sandstone from Utah, Arizona, and Colorado. The Nugget Sandstone of Wyoming, Utah, and southern Idaho, and the Aztec Sandstone of southeastern California and southern Nevada were determined to be laterally equivalent to ...
A Mineralogical And Geochemical Analysis Of Bed I In Olduvai Gorge, Tanzania, 2016 Georgia State University
A Mineralogical And Geochemical Analysis Of Bed I In Olduvai Gorge, Tanzania, David Michael Davis, Sanam M. Chaudhary, Alex M. Simpson, Daniel M. Deocampo, Nathan M. Rabideaux, Gail Ashley, Kevin Garrett
Georgia State Undergraduate Research Conference
No abstract provided.
Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland
Allen J. McGrew
New mapping, structural analysis, and 40Ar/39Ar dating reveal an unusually well‐constrained history of Late Eocene extension in the Copper Mountains of the northern Basin and Range province. In this area, the northeast‐trending Copper Creek normal fault juxtaposes a distinctive sequence of metacarbonate and granitoid rocks against a footwall of Upper Precambrian to Lower Cambrian quartzite and phyllite. Correlation of the hanging wall with footwall rocks to the northwest provides an approximate piercing point that requires 8–12 km displacement in an ESE direction. This displaced fault slice is itself bounded above by another normal fault (the Meadow ...
Differentiating Saginaw From Huron-Erie Lce Lobe Meltwater Deposits In South Central Michigan Using Longitudinal Profiles, Grain Size Analysis, And Lithology, Nathan R. Erber
The Saginaw and Huron-Erie lobes of the Laurentide Ice Sheet had a significant impact on the landscape of south-central Michigan after the Late Glacial Maximum. During the advances and retreats of these lobes, a complicated network of meltwater channels developed. Two goals of this study are: 1) to use sand-grain lithology, grain-size analysis, and longitudinal profiles to determine if a difference exists between Saginaw lobe and Huron-Erie lobe meltwater deposits; and 2) to determine if a large meltwater sluiceway containing the modern St. Joseph River had a source of meltwater and outwash from the Huron-Erie lobe. Two cores from drumlinized ...
Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera, 2016 Florida International University
Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera, Crystal Pletka
FIU Electronic Theses and Dissertations
The Neogene history of Caribbean deep-sea benthic foraminifera was investigated by calculating changes in paleoproductivity, diversity and paleobiogeography ~26 to 2 Ma, which includes the progressive closure of the Central American Seaway. Three hypotheses were tested: (1) Paleoproductivity values prior to closure of the Central American Seaway are similar in both the Caribbean and equatorial Pacific and then diverge by the time of early shoaling events; (2) Diversity values of benthic foraminifera prior to the closure of the Central American Seaway were similar in the Caribbean and EEP, and had changed by the time of early shoaling; and (3) during ...
Correspondence Of Historic Salinity Fluctuations In Florida Bay, Usa, To Atmospheric Variability And Anthropogenic Changes, 2016 Department of Earth and Environment and Southeast Environmental Research Center, Florida International University
Correspondence Of Historic Salinity Fluctuations In Florida Bay, Usa, To Atmospheric Variability And Anthropogenic Changes, Anna Wachnicka, Evelyn Gaiser, Laurel Collins
Evelyn E. Gaiser
Florida Bay is a highly dynamic estuary that exhibits wide natural fluctuations in salinity due to changes in the balance of precipitation, evaporation and freshwater runoff from the mainland. Rapid and large-scale modification of freshwater flow and construction of transportation conduits throughout the Florida Keys during the late nineteenth and twentieth centuries reshaped water circulation and salinity patterns across the ecosystem. In order to determine long-term patterns in salinity variation across the Florida Bay estuary, we used a diatom-based salinity transfer function to infer salinity within 3.27 ppt root mean square error of prediction from diatom assemblages from four ...
Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, 2016 Hydro Tasmania Consulting
Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar
Umesh K. Haritashya
Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than ...
Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, 2016 University of Colorado
Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe
The Chugach Mountains contain the largest nonpolar alpine glaciers in the world and include a wide variety of glacier types: some are land terminating; some calve variously into tidewater, lakes, and rivers; some are heavily debris covered; some are surge-type, whereas others are neither debris covered nor surge type. Nearly all are retreating, thinning, or both, though some rare ones are advancing, and some are thickening at high elevations. To assist the further documentation of changes, we establish an inventory of glaciers in the eastern Chugach Mountains. Several case studies of diverse glacier types showcase remotesensing applications and are used ...
Microbially Induced Sedimentary Structures In The Paleoproterozoic, Upper Huronian Supergroup, Canada, 2016 The University of Western Ontario
Microbially Induced Sedimentary Structures In The Paleoproterozoic, Upper Huronian Supergroup, Canada, Carolyn Hill, Patricia I. Corcoran, Rohan Aranha, Fred Longstaffe
Earth Sciences Publications
The Paleoproterozoic Gordon Lake and Bar River formations, Huronian Supergroup, contain a variety of sedimentary structures in the Flack Lake area of Ontario, Canada, that have been considered of debatable origin. We identify these structures as microbially induced sedimentary structures (MISS). The preserved MISS are related to microbial mat destruction and decay, and include sand cracks, mat chips, remnant gas domes, pyrite patches, and iron laminae. A biological origin for the fossil structures is supported by their similarities to modern and ancient documented examples of MISS, the sand-dominated nature of the substrate in which they are preserved, and key microtextures ...
Late Pleistocene Glaciations And Catastrophic Glacial Floods Of Central Colorado, 2016 University of Colorado Boulder, Department of Geological Sciences
Late Pleistocene Glaciations And Catastrophic Glacial Floods Of Central Colorado, Cole C. Pazar
Undergraduate Honors Theses
Late Pleistocene glaciations of the Sawatch and Elk Mountain Ranges of Central Colorado at ~130 and ~20 ka left behind glacial features in the topography, ideal for constraining the local climactic variability. In the northern end of the Sawatch Range, distinct lateral and terminal moraines reveal strong geologic evidence that multiple large glaciers drained eastward. Two of these appear to have dammed the Arkansas River. Very fine-grained lacustrine sediments, ‘ice-rafted’ boulders, and catastrophic glacial flood boulders down-valley, show at least two glacial-ice dammed lakes that catastrophically drained. We report flood discharge calculations consistent with previous estimates, on the order of ...
Lateral Variations In Sediment Provenance And Grain Size Along The Baffin Island Slope, 2016 University of Colorado, Boulder
Lateral Variations In Sediment Provenance And Grain Size Along The Baffin Island Slope, Anna Klein
Undergraduate Honors Theses
Baffin Bay is a 689,000 km2 basin linking the Arctic and the North Atlantic oceans. Nearby ice sheets and their ice streams are responsible for eroding, transporting, and depositing sediment of various size fractions on the sea floor. For over thirty years, geologists have known of the presence of detrital carbonate-rich (DC-) facies in the Baffin Bay Quaternary sediment sequence. It has been demonstrated that the distribution of marine carbonate facies, carbonate sources on land, and carbonate on the floors of the large Canadian Arctic Channels can reveal a relationship between land and sea records. This thesis aims ...