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Highway Construction Or Stream Destruction: A Water Quality Analysis In The Black Warrior Basin, Walker County, Alabama, Cayla Baughn 2018 Western Kentucky University

Highway Construction Or Stream Destruction: A Water Quality Analysis In The Black Warrior Basin, Walker County, Alabama, Cayla Baughn

Mahurin Honors College Capstone Experience/Thesis Projects

In 2012, residents along Freeman Branch Creek in Eldridge, Alabama observed unusual orange discoloration along the stream and on stream vegetation; an unprecendented black veneer coating pebbles along the streambed; and life in the stream seemed to have vanished. Freeman Branch Creek is located in Walker County, Alabama, which is known for its production of coal and natural gas from the underlying Pennsylvanian-aged Pottsville Formation, which is the uppermost geologic layer within the the Black Warrior Basin. Concerns for environmental safety related to intensive mining operations include the concern that shallow aquifers will be contaminated by mining in deep reservoir …


Evidence Of The 1762 Arakan And Prior Earthquakes In The Northern Sunda Subduction, Dhiman Ranjan Mondal 2018 CUNY Graduate Center

Evidence Of The 1762 Arakan And Prior Earthquakes In The Northern Sunda Subduction, Dhiman Ranjan Mondal

Dissertations, Theses, and Capstone Projects

The objective of this dissertation is to understand the seismic hazard associated with Arakan segment of the northern Sunda subduction along SE Bangladesh. In order to do that, it is necessary to document geologic evidence for the 1762 Arakan earthquake and prior events, to help estimate the recurrence interval (repeat time) for that earthquake. Historical records described that the 1762 earthquake caused extensive damage along the Arakan segment of the Sunda subduction system. But the geologic evidence for the earthquake farther north is necessary to better understand its associated seismic hazard to the densely populated nation of Bangladesh. This dissertation …


Lidar-Based Characterization And Conservation Of The First Theropod Dinosaur Trackways From Arkansas, Usa, Brian F. Platt, Celina A. Suarez, Stephen K. Boss, Malcolm Williamson, Jackson Cothren, Jo Ann C. Kvamme 2018 University of Mississippi

Lidar-Based Characterization And Conservation Of The First Theropod Dinosaur Trackways From Arkansas, Usa, Brian F. Platt, Celina A. Suarez, Stephen K. Boss, Malcolm Williamson, Jackson Cothren, Jo Ann C. Kvamme

Geosciences Faculty Publications and Presentations

LIDAR-based analyses of the first theropod dinosaur trackways known from the state of Arkansas, USA are reported. The trackways were found on a limestone bedding plane in the Albian De Queen Formation in an active gypsum quarry. Because limited access precluded thorough field study, fieldwork focused on preserving the entire site digitally with ground-based LIDAR, and detailed measurements were later taken digitally from point cloud data. The site contains eight tridactyl trackways associated with sauropod trackways and numerous isolated tracks. Although there appear to be two different tridactyl morphotypes, we show that the tracks are all likely from a single …


Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr. 2018 University of Nebraska-Lincoln

Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

In his new best-selling book, Peter Brannen, award-winning science writer, takes you on a fascinating trip through the run-up to the end of the Cretaceous extinction event and the K-Pg (Cretaceous/Paleogene) boundary, formerly called the K-T (Cretaceous/Tertiary) boundary.

Brannen interviewed many scientists who studied these events and went on field trips with them to major Cretaceous sites and to those where earlier and later extinction events happened. He presents clear explanations of what is known and not known about all of these events in a largely error-free book. Brannen details the other four big extinction events in geologic history: the …


Flume Tests On Fluvial Erosion Mechanisms In Tillbed Channels, L Pike, Peter Ashmore, S Gaskin 2018 McGill University

Flume Tests On Fluvial Erosion Mechanisms In Tillbed Channels, L Pike, Peter Ashmore, S Gaskin

Geography & Environment Publications

Semi-alluvial stream channels eroded into till and other glacial sediments are common in areas of extensive glacial deposition such as the Great Lakes region and northern interior plains of North America. The mechanics of erosion and erosional weakness of till results in the dominance of fluvial scour and mass erosion due to spontaneous fracture at planes of weakness under shearing flow. There have been few controlled tests looking at erosional mechanisms and resistance of till in river channels.We subjected small blocks of till to unidirectional flows in a laboratory flume to measure the threshold shear stress for erosion and observed …


Transforming Toronto's Rivers: A Socio-Geomorphic Perspective, Peter Ashmore 2018 Western University

Transforming Toronto's Rivers: A Socio-Geomorphic Perspective, Peter Ashmore

Geography & Environment Publications

No abstract provided.


The Pothole Hydrology-Linked Systems Simulator (Phyliss)—Development And Application Of A Systems Model For Prairie-Pothole Wetlands, Owen P. McKenna, David M. Mushet, Eric J. Scherff, Kyle I. McLean, Christopher T. Mills 2018 U.S. Department of the Interior & U.S. Geological Survey

The Pothole Hydrology-Linked Systems Simulator (Phyliss)—Development And Application Of A Systems Model For Prairie-Pothole Wetlands, Owen P. Mckenna, David M. Mushet, Eric J. Scherff, Kyle I. Mclean, Christopher T. Mills

United States Geological Survey: Publications

The North American Prairie Pothole Region covers about 770,000 square kilometers of the United States and Canada (including parts of 5 States and 3 provinces: North Dakota, South Dakota, Montana, Minnesota, Iowa, Saskatchewan, Manitoba, and Alberta). The Laurentide Ice Sheet shaped the landscape of the region about 12,000 to 14,000 years ago. The retreat of the ice sheet left behind low-permeability glacial till and a landscape dotted with millions of depressions known today as prairie potholes. The wetlands that subsequently formed in these depressions, prairie-pothole wetlands, provide critical migratory-bird habitat and support dynamic aquatic communities. Extensive grasslands and productive agricultural …


Appendix 1. Testing The Influence Of Management Regime And Year On Vegetation Structure Variables On Two Grass Types On Federal Lands Managed Under An Adaptive-Management Framework By The U.S. Fish And Wildlife Service In North Dakota, South Dakota, Minnesota, And Montana, 2011–13, J.J Gannon, T.L. Shaffer, C.T. Moore 2018 Native Prairie Adaptive Management

Appendix 1. Testing The Influence Of Management Regime And Year On Vegetation Structure Variables On Two Grass Types On Federal Lands Managed Under An Adaptive-Management Framework By The U.S. Fish And Wildlife Service In North Dakota, South Dakota, Minnesota, And Montana, 2011–13, J.J Gannon, T.L. Shaffer, C.T. Moore

United States Geological Survey: Publications

Generalized linear mixed model (assuming a beta distribution with a logit link) testing the influence of management regime and year on mean bare-ground cover (percent) on two grass types on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service (Gannon and others, 2013) in North Dakota, South Dakota, Minnesota, and Montana, 2011–13.


Impacts Of Vegetation Growth On Reach-Scale Flood Hydraulics In A Sand-Bed River And The Implications For Vegetation-Morphology Coevolution, Samuel Box 2018 University of Montana, Missoula

Impacts Of Vegetation Growth On Reach-Scale Flood Hydraulics In A Sand-Bed River And The Implications For Vegetation-Morphology Coevolution, Samuel Box

Graduate Student Theses, Dissertations, & Professional Papers

Vegetation affects river morphology via plant effects on the flow field, sediment transport and deposition, and substrate erodibility. Changes in the flow field caused by above-ground biomass mediate geomorphic response to flooding and habitat suitability for vegetation growth. Using numerical hydraulic models that incorporate drag due to spatially heterogeneous vegetation, I quantify how changes in the antecedent characteristics of woody vegetation in the active channel lead to changes in local bed shear stress, reach-average bed shear stress, and the vegetative component of reach-average total shear stress. Flood hydraulics in turn affect channel morphology and vegetation, providing a feedback mechanism by …


The Origin Of Dark Mats At The Sunrise Ridge Borrow Pit Site (45pi408) Mount Rainier National Park, Washington, Sean Stcherbinine 2018 Central Washington University

The Origin Of Dark Mats At The Sunrise Ridge Borrow Pit Site (45pi408) Mount Rainier National Park, Washington, Sean Stcherbinine

All Master's Theses

The Sunrise Ridge Borrow Pit Site is a precontact archaeological site located in the upland forest soils of Mount Rainier National Park. Site stratigraphy is complicated, consisting of tephra deposits from mostly known origins that are intercalated with dark sediments of unknown origin, referred to here as dark mats. Precontact occupation has been split previously into two components based on the ambiguous depositional history of the dark mats, notably their unknown parent material, depositional environment, and relationship with adjacent tephra strata. Stratigraphic samples from excavation units, features, and one off-site excavation unit was used to investigate these data gaps. Grain …


Assessing The Impact Of The Conservation Reserve Program On Honey Bee Health, Otto, C.R.V., O'Dell, S., Bryant, R.B., Euliss, N.H., Bush 2018 University of Nebraska - Lincoln

Assessing The Impact Of The Conservation Reserve Program On Honey Bee Health, Otto, C.R.V., O'Dell, S., Bryant, R.B., Euliss, N.H., Bush

United States Geological Survey: Publications

Insect pollinators are critically important for maintaining U.S. food production and ecosystem health. The upper Midwest is home to more than 40 percent of all U.S. honey bee colonies and is considered by many beekeepers to be America’s last beekeeping refuge. Beekeepers come to this region because their honey bees require high-quality grassland and bee-friendly agricultural crops to make honey and to improve bee health. Agricultural grassland, such as those enrolled in the Conservation Reserve Program (CRP), support flowers that provide bees with the pollen and nectar they need. In 2014, the U.S. Department of Agriculture (USDA) and the U.S. …


Adaptive Management In Native Grasslands Managed By The U.S. Fish And Wildlife Service—Implications For Grassland Birds, Lawrence D. Igl, Welsey E. Newton, Todd A. Grant, Cami S. Dixon 2018 U.S. Geological Survey.

Adaptive Management In Native Grasslands Managed By The U.S. Fish And Wildlife Service—Implications For Grassland Birds, Lawrence D. Igl, Welsey E. Newton, Todd A. Grant, Cami S. Dixon

United States Geological Survey: Publications

Burning and grazing are natural processes in native prairies that also serve as important tools in grassland management to conserve plant diversity, to limit encroachment of woody and invasive plants, and to maintain or improve prairies. Native prairies managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region of the northern Great Plains have been extensively invaded by nonnative, cool-season species of grasses. These invasions were believed to reflect a common management history of long-term rest and little or no defoliation by natural processes (burning and grazing). To address the challenges associated with these invasive species, …


Combining Hydraulic Head Analysis With Airborne Electromagnetics To Detect And Map Impermeable Aquifer Boundaries, Jesse T. Korus 2018 University of Nebraska-Lincoln

Combining Hydraulic Head Analysis With Airborne Electromagnetics To Detect And Map Impermeable Aquifer Boundaries, Jesse T. Korus

Conservation and Survey Division: Faculty and Staff Publications

Impermeable aquifer boundaries affect the flow of groundwater, transport of contaminants, and the drawdown of water levels in response to pumping. Hydraulic methods can detect the presence of such boundaries, but these methods are not suited for mapping complex, 3D geological bodies. Airborne electromagnetic (AEM) methods produce 3D geophysical images of the subsurface at depths relevant to most groundwater investigations. Interpreting a geophysical model requires supporting information, and hydraulic heads offer the most direct means of assessing the hydrostratigraphic function of interpreted geological units. This paper presents three examples of combined hydraulic and AEM analysis of impermeable boundaries in glacial …


The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard 2018 University of Nebraska-Lincoln

The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Red Willow County that has not been published in readily accessible formats previously. Many of the maps presented here are based on geologic information from registered wells and test holes that is publically available on-line, which becomes more valuable when compiled, analyzed, and discussed as a whole.

In Red Willow County, the aquifers are alluvial sand and gravel in the river and stream valleys and the High Plains aquifer beneath the uplands. The High Plains aquifer in Red Willow County consists primarily of the Ogallala …


Persistence Of Stream Restoration With Large Wood, Redwood National And State Parks, California, Diedra L. Rodriguez 2018 Cal Poly Humboldt

Persistence Of Stream Restoration With Large Wood, Redwood National And State Parks, California, Diedra L. Rodriguez

Cal Poly Humboldt theses and projects

The conservation and recovery of anadromous salmonids (Oncorhynchus sp.) depend on stream restoration and protection of freshwater habitats. In-stream large wood dictates channel morphology, increases retention of terrestrial inputs such as organic matter, nutrients and sediment, and enhances the quality of fish habitat. Historic land use/land cover changes have resulted in aquatic systems devoid of large wood. Restoration by placement of large wood jams is intended to restore physical and biological processes. An important question for scientists and restoration managers, in addition to the initial effectiveness of restoration, is the persistence and fate of large wood installations. In this …


Quantifying Sedimentation Patterns Of Small Watersheds In The Central Oregon Coast Range Using Landslide-Dammed Lakes, Logan Wetherell 2018 Central Washington University

Quantifying Sedimentation Patterns Of Small Watersheds In The Central Oregon Coast Range Using Landslide-Dammed Lakes, Logan Wetherell

All Master's Theses

Up to 250 years of sedimentation patterns in headwater streams are preserved with detail in landslide-dammed lakes of the central Oregon Coast Range. I hypothesize that both anthropogenic and natural perturbations should increase linear and mass sediment accumulation rates and be discernible spatially and temporally in the sediment record with use of 137Cs, high resolution charcoal stratigraphy, and aerial photography. Klickitat Lake and Wasson Lake are landslide-dammed lakes in small watersheds (<10 >km2) that contain drowned Douglas-fir stumps that are used for accurate dendrochronology and precise timing of the lake formation. An age-depth relationship was developed using …


Abandoned Mine Land Impacts On Tributaries In The Upper Yakima River Watershed, Eastern Cascades, Washington, Scott Kugel 2018 Central Washington University

Abandoned Mine Land Impacts On Tributaries In The Upper Yakima River Watershed, Eastern Cascades, Washington, Scott Kugel

All Master's Theses

Effluent from abandoned mine lands (AMLs) in several drainages in Washington’s Eastern Cascades flows into the Yakima River. Similar sites in Idaho and Colorado are known producers of heavy metals and acid mine drainage. I determined the effects of nine AMLs on water quality in four tributaries to the Yakima River. Archival work was conducted to determine sites that were mined and contained a mill. Each site was characterized by physical features. Water and sediment samples were collected above, at, and below each AML. Samples were analyzed for pH and heavy metal content, and evaluated to determine if the AMLs …


Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle 2018 Central Washington University

Internal Composition, Structure, And Hydrological Significance Of Rock Glaciers In The Eastern Cascades, Washington, Adam Riffle

All Master's Theses

Low summer river base flow places a strain on natural and economic resources of the Eastern Cascades. A major contributor to stream flow in this region is snow pack which has declined over the past few decades because of a warming climate. In addition, glacial runoff, which contributes significantly to base flow in summer dry periods, will diminish from glacial recession. However, rock glaciers, because their internal ice (i.e., permafrost) is insulated by an outer debris layer, react slowly to climate change, thus acting as sinks for ice and liquid water storage in mountain environments. This study utilized ground penetrating …


Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver 2018 Central Washington University

Geomorphic Consequences Of Hydroelectricity And Transportation Development Near Celilo Falls, Lower Mid-Columbia River, Washington, Noah I. Oliver

All Master's Theses

Along the Columbia River, hundreds of miles of transportation infrastructure and over sixty hydroelectric dams have been constructed. This altered a rich cultural landscape with evidence of 10,000 years of continuous occupation. Researchers have attempted to understand the impacts of anthropogenic factors on the Columbia River, focusing on the riverine environment. However, the effect of transportation and hydroelectricity developments to eolian landforms on the floodplains and adjoining slopes have not been studied. Focusing on 2,800 acres near Celilo Falls, this study 1) establishes a baseline condition of eolian landforms from 1805 to 1900; 2) conducts an air photo increment analysis …


Comparison Of Karstification Methods And Isostatic Rebound In The Suwannee River Basin, Florida, Toni Larche 2018 Michigan Technological University

Comparison Of Karstification Methods And Isostatic Rebound In The Suwannee River Basin, Florida, Toni Larche

Dissertations, Master's Theses and Master's Reports

Plio-Pleistocene beach ridges in northern Florida are nearly 50 m above current sea level, but sea level during that time is not known to have been more than 25 m above current sea level. The height of beach ridges in northern Florida therefore create a conundrum because Florida is located on a passive margin in what is considered a tectonically stable environment. A series of recent studies have suggested that uplift on the Florida peninsula may be the result of the removal of subsurface crustal mass. Karstification of Florida’s carbonate matrix may provide a mechanism for subsurface crustal mass removal …


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