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Stratigraphic Architecture And Lithofacies Of High-Frequency Deltaic Sequences: Virtual Outcrop Analysis Of The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Conor J. Horton 2017 University of Nebraska-Lincoln

Stratigraphic Architecture And Lithofacies Of High-Frequency Deltaic Sequences: Virtual Outcrop Analysis Of The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Conor J. Horton

Dissertations & Theses in Earth and Atmospheric Sciences

Sequence stratigraphic models for low-accommodation settings are not well-formulated and lack documented examples illustrating lithofacies stratal stacking pattern complexities. Presented herein is a detailed stratigraphic analysis of the Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale Formation; a fluvial-deltaic succession that primarily accumulated under forced-regressive, falling stage systems tracts during decreasing accommodation. The small (4 km2) study area is located at the connecting point of a 67 km long, depositional strike-oriented and a 30 km long, depositional-dip transect within the western-limb of the Henry Mountains Syncline. Detailed outcrop sections and digital Light Detection and Ranging (LiDAR) derived Virtual ...


Middle Miocene Paleoenvironmental Reconstruction Of The Central Great Plains From Stable Carbon Isotopes In Large Mammals, Willow H. Nguy 2017 University of Nebraska-Lincoln

Middle Miocene Paleoenvironmental Reconstruction Of The Central Great Plains From Stable Carbon Isotopes In Large Mammals, Willow H. Nguy

Dissertations & Theses in Earth and Atmospheric Sciences

Middle Miocene (18-12 Mya) mammalian faunas of the North American Great Plains contained a much higher diversity of apparent browsers than any modern biome. This has been attributed to greater primary productivity, which may have supported greater browser diversity that commonly corresponds with densely vegetated habitats. However, several lines of proxy evidence suggest that open woodlands or savannas dominated middle Miocene biomes; neither of which support many browsers today. Stable carbon isotopes in mammalian herbivore tooth enamel were used to reconstruct vegetation structure of middle Miocene biomes.

Stable carbon isotopes in C3 dominated environments reflect vegetation density and herbivores ...


A Case Study In Basement And Surface Structure Relationships And Their Implications For Fault Reactivation, Sawtooth Range, Mt, Jason M. Palu 2017 University of Nebraska-Lincoln

A Case Study In Basement And Surface Structure Relationships And Their Implications For Fault Reactivation, Sawtooth Range, Mt, Jason M. Palu

Dissertations & Theses in Earth and Atmospheric Sciences

The reactivation of pre-existing basement structures affects the geometry of subsequent deformation structures. A case study analyzing the results of these interactions can be used to examine multiple fold-thrust systems and lead to valuable deformation predictions. These predictions include the potential for hydrocarbon traps or seismic risk in an actively deforming area. This case study examined the development of structures close to the Augusta Syncline in the Sawtooth Range, Montana (USA), using: 1) an ArcGIS map of basement structures, based on analysis of gravimetric and aeromagnetic data, seismic data, and well logs; 2) an ArcGIS map of the surface deformation ...


Epikarst Hydrogeochemical Changes In Telogenetic Karst Systems In South-Central Kentucky, Leah Jackson 2017 Western Kentucky University

Epikarst Hydrogeochemical Changes In Telogenetic Karst Systems In South-Central Kentucky, Leah Jackson

Masters Theses & Specialist Projects

Telogenetic epikarst carbon sourcing and transport processes and the associated hydrogeochemical responses are often complex and dynamic. Among the processes involved in epikarst development is a highly variable storage and flow relationship that is often influenced by the type, rate, and amount of dissolution kinetics involved. Diffusion rates of CO2 in the epikarst zone may drive hydrogeochemical changes that influence carbonate dissolution processes and conduit formation. Most epikarst examinations of these defining factors ignore regional-scale investigations in favor of characterizing more localized processes. This study aims to address that discrepancy through a comparative analysis of two telogenetic epikarst systems under ...


Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Turner 2017 Western Kentucky University

Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Turner

Masters Theses & Specialist Projects

Rising atmospheric CO2 concentrations have motivated efforts to better quantify reservoirs and fluxes of Earth’s carbon. Of these fluxes from the atmosphere, one that has received relatively little attention is the atmospheric carbon sink associated with carbonate mineral dissolution. Osterhoudt (2014) and Salley (2016) explored new normalization techniques to improve and standardize a process for measuring this flux over large river basins. The present research extends this work to the 490,600 km2 Ohio River drainage basin and 11 subbasins. The study estimated the DIC flux leaving these basins between October 1, 2013, and September 30, 2014, based on ...


Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, R M Malitha Chanuka Bandara Rathnayake 2017 The University of Southern Mississippi

Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, R M Malitha Chanuka Bandara Rathnayake

Master's Theses

The Mississippi River Basin is the largest river basin in North America and the third largest river basin in the world. Most of the corn, soybeans, wheat, cattle, and hogs harvested in the United States come from the Mississippi River Basin and about 58% of the entire drainage basin is croplands. Runoff from these lands carries sediments and nutrients, and the Mississippi River transports these downstream and ultimately deposits them in the Gulf of Mexico. The northern Gulf of Mexico is one of largest human-caused hypoxic zones in the world. Hypoxia is the phenomena where the dissolved oxygen level decreases ...


An Overview Of Secondary Aquifers In Nebraska, Dana P. Divine, Steven S. Sibray 2017 University of Nebraska - Lincoln

An Overview Of Secondary Aquifers In Nebraska, Dana P. Divine, Steven S. Sibray

Conservation and Survey Division

No abstract provided.


Great Plains Geology: My Personal Journey, Robert Diffendal, Jr. 2017 University of Nebraska - Lincoln

Great Plains Geology: My Personal Journey, Robert Diffendal, Jr.

Robert F. Diffendal, Jr., Publications

In 2014 my good friend and former boss, Richard (Rick) Edwards, Director of the University of Nebraska's Center for Great Plains Studies asked me to consider writing a small book about the geology of the Great Plains as part of a series of books exploring many aspects of this marvelous place. I thought his request over and told Rick that I would give it a try. The series is being published by the University of Nebraska Press, the first completed book of which is Great Plains Indians written by my colleague David Wishart.

I wrote up an outline of ...


Origins Of Late- Pleistocene Coastal Dune Sheets, Magdalena And Guerrero Negro, From Continental Shelf Low-Stand Supply (70-20 Ka), Under Conditions Of Southeast Littoral- And Eolian-Sand Transport, In Baja California Sur, Mexico, Curt D. Peterson, Janette Murillo-Jiminez, Errol Stock, David M. Price, Steve W. Hostetler, David Percy 2017 Portland State University

Origins Of Late- Pleistocene Coastal Dune Sheets, Magdalena And Guerrero Negro, From Continental Shelf Low-Stand Supply (70-20 Ka), Under Conditions Of Southeast Littoral- And Eolian-Sand Transport, In Baja California Sur, Mexico, Curt D. Peterson, Janette Murillo-Jiminez, Errol Stock, David M. Price, Steve W. Hostetler, David Percy

Geology Faculty Publications and Presentations

Shallow morpho-stratigraphic sections (n = 11) in each of two large coastal dune sheets including the Magdalena (7000 km2) and Guerrero Negro (8000 km2) dune sheets, from the Pacific Ocean side of Baja California Sur, Mexico, have been analyzed for dune deposit age. The shallow morpho-stratigraphic sections (∼2-10 m depth) include 11 new TL and 14C ages, and paleosol chronosequences, that differentiate cemented late Pleistocene dune deposits (20.7 ± 2.1 to 99.8 ± 9.4 ka) from uncemented Holocene dune deposits (0.7 ± 0.05 to at least 3.2 ± 0.3 ka). Large linear dune ridges (5-10 ...


Analysis Of The Hite Fault Group, Southeast Utah: Insights Into Fluid Flow Properties In A Reservoir Analog, Daniel J. Curtis 2017 Utah State University

Analysis Of The Hite Fault Group, Southeast Utah: Insights Into Fluid Flow Properties In A Reservoir Analog, Daniel J. Curtis

All Graduate Theses and Dissertations

In the subsurface faults can act as both barriers and conduits for fluids or gases such as CO2, hydrocarbons, or water. It is often thought that faults in porous rocks such as sandstone are barriers to fluid flow. In this study we show that this is not always the case. In sandstones like the Cedar Mesa Sandstone it is very important to understand the relationships between this history of fault slip and fluid flow. Better understanding of how fluids migrate through faults and the damaged areas surrounding these faults has strong significance to the oil and gas industry.

In ...


Analyzing Glacier Surface Motion Using Lidar Data, Jennifer W. Tellig, Craig Glennie, Andrew G. Fountain, David C. Finnegan 2017 University of Houston

Analyzing Glacier Surface Motion Using Lidar Data, Jennifer W. Tellig, Craig Glennie, Andrew G. Fountain, David C. Finnegan

Andrew G. Fountain

Understanding glacier motion is key to understanding how glaciers are growing, shrinking, and responding to changing environmental conditions. In situ observations are often difficult to collect and offer an analysis of glacier surface motion only at a few discrete points. Using light detection and ranging (LiDAR) data collected from surveys over six glaciers in Greenland and Antarctica, particle image velocimetry (PIV) was applied to temporally-spaced point clouds to detect and measure surface motion. The type and distribution of surface features, surface roughness, and spatial and temporal resolution of the data were all found to be important factors, which limited the ...


Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. DiBiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth 2017 Pennsylvania State University

Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. Dibiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth

Adam M. Booth

Existing hillslope sediment transport models developed for low-relief, soil-mantled landscapes are poorly suited to explain the coupling between steep rocky hillslopes and headwater channels. Here we address this knowledge gap using a series of field and numerical experiments to inform a particle-based model of sediment transport by dry ravel—a mechanism of granular transport characteristic of steep hillslopes. We find that particle travel distance increases as a function of the ratio of particle diameter to fine-scale (1m) topographic variability associated with rocky landscapes. Applying a 2-D dry-ravel-routing model to lidar-derived surface topography, we show how spatial patterns of local and ...


Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera 2017 Universidad de Zaragoza

Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera

International Journal of Speleology

Evaluation of karst hazards benefits from the integration of different techniques, methodologies and approaches. Each one presents a different signature and is sensitive to certain indicators related to karst hazards. In some cases, detailed analysis permits the evaluation of representativeness either from isolated approaches or by means of integrated analyses. In this study, we present the evaluation of an area with high density of karstic collapses at different evolutionary stages through the integration of surficial, historical, geomorphological and geophysical data in order to finally define the evolutionary model for karst activity development. The obtained dataset permits to identify different steps ...


Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz de la Torre 2017 University of Málaga

Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz De La Torre

International Journal of Speleology

The geomorphological characteristics and hydrogeological functioning of a geologically heterogeneous evaporitic karst plateau in Southern Spain were studied. Land surface information (LiDAR data) was used to analyze the shape and distribution of closed depressions. An artificial tracer test and monitoring of the natural responses of the main spring have allowed to infer the karstic development of the studied system. Three dyes were injected in selected swallow holes to trace the main groundwater flowpaths and to estimate the dimension of the conduit network. Discharge, electrical conductivity and temperature were monitored in the groundwater that drains the evaporitic plateau during an individual ...


Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele 2017 Polytechnic University of Turin

Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele

International Journal of Speleology

A Messinian succession containing gypsum beds crops out in northern Italy, mainly in Piedmont and along the northern flank of the Apennine mountains in Emilia-Romagna. These gypsum bodies have been extensively quarried at the surface, in outcrops, and through underground quarries. In Emilia-Romagna these gypsum outcrops can be rather extensive, several km long and up to 1 km wide, while in Piedmont they are mostly covered by silty-marly deposits of Upper Messinian and Pliocene age and show only sparse and small outcrops. The underground quarrying of these evaporite bodies in Piedmont has allowed studying in detail their hydrogeology, and the ...


Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine 2017 University of Nebraska - Lincoln

Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine

Conservation and Survey Division

No abstract provided.


Sedimentology And Taphonomy Of The Abydosaurus Mcintoshi Quarry, (Naturita Formation, Early Cretaceous, Latest Albian), Dinosaur National Monument, Utah, Aaron Daniel Holmes 2017 Brigham Young University

Sedimentology And Taphonomy Of The Abydosaurus Mcintoshi Quarry, (Naturita Formation, Early Cretaceous, Latest Albian), Dinosaur National Monument, Utah, Aaron Daniel Holmes

All Theses and Dissertations

The holotypic locality of the brachiosaurid titanosauriform sauropod, Abydosaurus mcintoshi, is quarry DNM-16, located in Dinosaur National Monument. The bones are preserved near the base of a heterolithic, trough cross stratified to planar bedded sandstone channel complex. The trough cross to planar bedded sandstones mark times of variable flow with times of high flow velocity based on bones whose upper surfaces were eroded before final burial. The abundance of mud with the dominant medium to fine sand, and poorly confined sandstone channels indicate the bones were transported and buried in medial to distal intermittent flows of a distributive fluvial system ...


The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell 2017 University of San Diego

The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell

Theses

In the US Virgin Islands (USVI), land-based (terrigenous) sedimentation has been identified as a major cause of coral stress. Development, such as the building of unpaved roads in steep coastal watersheds, has increased sediment yields and marine terrigenous sedimentation by up to an order of magnitude above background levels. When activated during storm events, ephemeral streams transport sediment from the watershed to coastal waters. Once deposited on the seafloor, resuspension of benthic sediments can further increase turbidity and deposition. However, isolating the relative contributions of runoff and resuspension to turbidity and deposition using conventional sediment trap monitoring has been challenging ...


Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle 2017 The University of San Francisco

Groundwater Vulnerability Assessment For Nitrate Pollution In The Salinas Valley Using A Modified Drastic Model, Bernadette Boyle

Master's Projects and Capstones

Groundwater is an integral piece of California’s groundwater resources. One of the most common contaminants present in groundwater is nitrate. Nitrate contamination is often a result of agricultural land use activities on the ground surface. The study area for this analysis is the Salinas Valley Groundwater Basin, an agriculturally dominated basin in coastal California. The Salinas Valley Basin is both one of the most agriculturally productive areas of the state, as well as one of the most nitrate-contaminated basins in the state. The purpose of this research was to develop a groundwater vulnerability map for nitrate pollution in the ...


Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon 2017 University of New Orleans

Overwash Controls On Barrier Island Morphodynamics During Storms, Joshua H. Alarcon

University of New Orleans Theses and Dissertations

Overwash, shoreface retreat, and barrier migration are common processes occurring in transgressive barrier island systems, the scale of which is exacerbated by sea level rise, subsidence and the frequency and magnitude of tropical and extratropical storms. Barrier morphology also clearly plays a key role in determining a morphological response to these processes. Using a hydrodynamic and sediment transport model (MIKE21) and selected barrier island and shoreface templates, informed by deltaic and coastal plain systems in the northern Gulf of Mexico, I performed simulations to determine barrier morphology in response to storms. A low dune with a gentle shoreface slope, characteristic ...


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