Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- University of Nebraska - Lincoln (498)
- University of South Florida (328)
- Western Kentucky University (243)
- University of Kentucky (161)
- West Virginia University (137)
-
- Illinois State University (120)
- Missouri State University (110)
- Portland State University (109)
- University of Arkansas, Fayetteville (108)
- Wilfrid Laurier University (97)
- Utah State University (90)
- TÜBİTAK (87)
- Boise State University (77)
- Chapman University (70)
- Missouri University of Science and Technology (70)
- Montclair State University (57)
- Old Dominion University (57)
- Central Washington University (55)
- City University of New York (CUNY) (54)
- South Dakota State University (54)
- Louisiana State University (53)
- University of Texas Rio Grande Valley (50)
- Western Michigan University (45)
- College of Saint Benedict and Saint John's University (44)
- University of Nevada, Las Vegas (43)
- The University of Southern Mississippi (39)
- University of South Carolina (36)
- Indiana State University (35)
- University of New Hampshire (35)
- China Coal Technology and Engineering Group (CCTEG) (34)
- Keyword
-
- Geology (142)
- Climate change (92)
- Remote sensing (88)
- GIS (80)
- Geomorphology (67)
-
- Hydrology (67)
- Western Kentucky University (60)
- Geochemistry (59)
- Karst (58)
- Water quality (57)
- Groundwater (55)
- Geography (44)
- Remote Sensing (42)
- Drought (40)
- Climate (35)
- Agriculture (34)
- United States (32)
- Paleoclimate (31)
- Montana (29)
- Stratigraphy (29)
- Fluvial geomorphology (28)
- Vegetation (28)
- Earth sciences (26)
- Western Australia (26)
- Nebraska (25)
- Land use (24)
- Machine learning (24)
- Geophysics (23)
- Holocene (23)
- Caves (22)
- Publication Year
- Publication
-
- International Journal of Speleology (167)
- United States Geological Survey: Staff Publications (142)
- Masters Theses & Specialist Projects (119)
- Theses and Dissertations (119)
- IGC Proceedings (1977-2023) (109)
-
- Graduate Theses/Dissertations (108)
- Department of Earth and Atmospheric Sciences: Faculty Publications (100)
- Theses and Dissertations (Comprehensive) (93)
- Turkish Journal of Earth Sciences (87)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (77)
- Geosciences Faculty Publications and Presentations (73)
- Electronic Theses and Dissertations (62)
- Graduate Theses and Dissertations (61)
- Masters Theses (61)
- School of Geosciences Faculty and Staff Publications (55)
- Glacial Deposits (48)
- Department of Earth and Environmental Studies Faculty Scholarship and Creative Works (46)
- Dissertations and Theses (46)
- The Compass: Earth Science Journal of Sigma Gamma Epsilon (44)
- Faculty Publications (43)
- USF Tampa Graduate Theses and Dissertations (40)
- School of Earth, Environmental, & Marine Sciences Faculty Publications (38)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (36)
- Geology Faculty Publications and Presentations (36)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (34)
- Coal Geology & Exploration (34)
- Conservation and Survey Division: Faculty and Staff Publications (34)
- All-Inclusive List of Electronic Theses and Dissertations (33)
- Mathematics, Physics, and Computer Science Faculty Articles and Research (33)
- Studia UBB Geologia (32)
- Publication Type
- File Type
Articles 1771 - 1800 of 3985
Full-Text Articles in Entire DC Network
Geology And Geochemistry Of The Uvas Volcanic Field And Rubio Peak Formation Of South-Central New Mexico, Usa, Max Logan Hoffman
Geology And Geochemistry Of The Uvas Volcanic Field And Rubio Peak Formation Of South-Central New Mexico, Usa, Max Logan Hoffman
Graduate Theses/Dissertations
South-central New Mexico is characterized by many Cenozoic volcanic and tectonic events that produced a complex system of magma sources. These mechanisms are responsible for the diverse volcanic activity and magmatic evolution in New Mexico. To understand the growth and development of the mantle sources associated with these events, geochemical, petrographic, structural and spatial distribution data were collected from the Uvas volcanic field (UVF) and the Rubio Peak Formation of the Mogollon-Datil volcanic field (MDVF). Volcanic rocks from these volcanic fields were chosen based on their importance to relative timing of magmatic and tectonic transitioning events. The structural and spatial …
Geomorphic Disturbance And Anthropogenic Modifications In Big Barren Creek, Mark Twain National Forest, Southeast Missouri, Rachael A. Bradley
Geomorphic Disturbance And Anthropogenic Modifications In Big Barren Creek, Mark Twain National Forest, Southeast Missouri, Rachael A. Bradley
Graduate Theses/Dissertations
This study investigates the influence of human disturbance on channel conditions in Big Barren Creek. The Big Barren watershed drains 191 km2 of the Ozark Highlands in southeast Missouri. Several segments of the creek have been channelized by levee construction and gravel mining. Approximately 27.2 km of the main stem of Barren Creek were assessed for 13 photo-years ranging from 1939 to 2014. Geomorphic classifications using channel conditions in aerial photographs and field observations were used to evaluate patterns of disturbance. While 52% of the creek is managed by private landowners, 81% of disturbed length occurs on private lands. Further, …
Urban Detention Basin Contamination With Polycyclic Aromatic Hydrocarbons (Pahs) And Metals, Holly Marie Duff
Urban Detention Basin Contamination With Polycyclic Aromatic Hydrocarbons (Pahs) And Metals, Holly Marie Duff
Graduate Theses/Dissertations
Polycyclic aromatic hydrocarbons (PAHs) are organic compounds that can be toxic to wildlife and humans when released to the environment. Coal-tar sealants, which are applied to parking lots or driveways, contribute up to 1,000 times more PAHs than alternative sealants. Over time, these sealants abrade and are transported into drainage networks. Coal-tar sealants are currently used in Springfield, Missouri, however the extent of PAH contamination throughout urban drainage systems is unclear. This study focused on PAH contamination within an urban detention basin on the Missouri State University campus which receives runoff from several coal-tar sealed parking lots. Sediment samples collected …
Regional Sensitivities Of Seasonal Snowpack To Elevation, Aspect, And Vegetation Cover In Western North America, Nancy F. Glenn
Regional Sensitivities Of Seasonal Snowpack To Elevation, Aspect, And Vegetation Cover In Western North America, Nancy F. Glenn
Geosciences Faculty Publications and Presentations
In mountains with seasonal snow cover, the effects of climate change on snowpack will be constrained by landscape-vegetation interactions with the atmosphere. Airborne lidar surveys used to estimate snow depth, topography, and vegetation were coupled with reanalysis climate products to quantify these interactions and to highlight potential snowpack sensitivities to climate and vegetation change across the western U.S. at Rocky Mountain (RM), Northern Basin and Range (NBR), and Sierra Nevada (SNV) sites. In forest and shrub areas, elevation captured the greatest amount of variability in snow depth (16–79%) but aspect explained more variability (11–40%) in alpine areas. Aspect was most …
The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic
The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic
Geology Faculty Publications and Presentations
A comprehensive mid-20th century inventory of glaciers and perennial snowfields (G&PS) was compiled for the American West, west of the 100° meridian. The inventory was derived from U.S. Geological Survey 1:24,000 topographic maps based on aerial photographs acquired during 35 years, 1955–1990, of which the first 20 years or more was a cool period with little glacier change. The mapped features were filtered for those greater than 0.01 km2. Results show that 5036 G&PS (672 km2, 14 km3) populate eight states, of which about 1276 (554 km2, 12 km3) are glaciers. …
Acquisition Of A 3 Min, Two-Dimensional Glacier Velocity Field With Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, David M. Holland, Ryan Cassotto, Ian M. Howat, Mark A. Fahnestock, Martin Truffer, Santiago De La Pena
Acquisition Of A 3 Min, Two-Dimensional Glacier Velocity Field With Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, David M. Holland, Ryan Cassotto, Ian M. Howat, Mark A. Fahnestock, Martin Truffer, Santiago De La Pena
School of Geosciences Faculty and Staff Publications
Outlet glaciers undergo rapid spatial and temporal changes in flow velocity during calving events. Observing such changes requires both high temporal and high spatial resolution methods, something now possible with terrestrial radar interferometry. While a single such radar provides line-of-sight velocity, two radars define both components of the horizontal flow field. To assess the feasibility of obtaining the two-dimensional (2-D) flow field, we deployed two terrestrial radar interferometers at Jakobshavn Isbrae, a major outlet glacier on Greenland's west coast, in the summer of 2012. Here, we develop and demonstrate a method to combine the line-of-sight velocity data from two synchronized …
If It Burns, Will It Flow? And About The Managers Who Would Like To Know: Predicting Post-Fire Debris Flows In The Rangeland Foothills Of Boise, Idaho & Investigating The Use Of Wildfire Science By Decision Makers At The Wildland Urban Interface, Katherine Gibble
Boise State University Theses and Dissertations
Wildfires increase erosion in mountainous landscapes. The most catastrophic form of post-fire erosion is the debris flow, viscous slurries of water and sediment capable of scouring and entraining larger sediment and rafting boulders. Post-fire debris flows are particularly hazardous when fire- and debris flow-prone landscapes intersect the Wildland Urban Interface (WUI). Homes built into the edge of the flammable WUI are at high risk of both wildfire and subsequent debris flows in mountainous landscapes of the western US, yet the WUI is expanding at an extraordinary rate. There are predictive models that inform citizens, land managers, and local governments of …
Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, R M Malitha Rathnayake
Sedimentary Characteristics And Nutrient Sequestration Of Embanked Floodplains Along The Lower Mississippi River, Mississippi And Louisiana, R M Malitha 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 …
Stratigraphy Of The Middle Cambrian Lincoln Peak Formation And Evolution Of The House Range Embayment, Eastern Nevada, Ibrahim Zallum
Stratigraphy Of The Middle Cambrian Lincoln Peak Formation And Evolution Of The House Range Embayment, Eastern Nevada, Ibrahim Zallum
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
This study examined the Middle Cambrian (c. 500 MA) Lincoln Peak Formation and Patterson Pass Shale. The initial goal was to create a stratigraphic model for these units. This model was then compared to those from already studied units in western Utah, which combined with the Nevada units form the rock record of an ancient feature known as the House Range Embayment, which was an area of greater water depth superimposed on the continental shelf. This study found that the Nevada units exhibit a series of depositional sequences similar to those in western Utah, but at a lower resolution. This …
Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang
Vulnerability Assessment Of Groundwater To No3 Contamination Using Gis, Drastic Model And Geostatistical Analysis, Adela Beauty Adu Agyemang
Electronic Theses and Dissertations
The study employed Geographical Information System (GIS) technology to investigate the vulnerability of groundwater to NO3 content in Buncombe County, North Carolina in two different approaches. In the first study, the spatial distribution of NO3 contamination was analyzed in a GIS environment using Kriging Interpolation. Cokriging interpolation was used to establish how NO3 relates to land cover types and depth to water table of wells in the county. The second study used DRASTIC model to assess the vulnerability of groundwater in Buncombe County to NO3 contamination. To get an accurate vulnerability index, the DRASTIC parameters were …
Effects Of Climate Warming On Net Primary Productivity In China During 1961–2010, Fengxue Gu, Yuandong Zhang, Mei Huang, Bo Tao, Rui Guo, Changrong Yan
Effects Of Climate Warming On Net Primary Productivity In China During 1961–2010, Fengxue Gu, Yuandong Zhang, Mei Huang, Bo Tao, Rui Guo, Changrong Yan
Plant and Soil Sciences Faculty Publications
The response of ecosystems to different magnitudes of climate warming and corresponding precipitation changes during the last few decades may provide an important reference for predicting the magnitude and trajectory of net primary productivity (NPP) in the future. In this study, a process-based ecosystem model, Carbon Exchange between Vegetation, Soil and Atmosphere (CEVSA), was used to investigate the response of NPP to warming at both national and subregional scales during 1961–2010. The results suggest that a 1.3°C increase in temperature stimulated the positive changing trend in NPP at national scale during the past 50 years. Regardless of the magnitude of …
Moving From Generalisations To Specificity About Mangrove –Saltmarsh Dynamics, Kerrylee Rogers, Ken W. Krauss
Moving From Generalisations To Specificity About Mangrove –Saltmarsh Dynamics, Kerrylee Rogers, Ken W. Krauss
United States Geological Survey: Staff Publications
Spatial and temporal variability in factors influencing mangrove establishment and survival affects the distribution of mangrove, particularly near their latitudinal limit, where mangrove expansion into saltmarsh is conspicuous. In this paper the spatial variability in mangrove distribution and variability in factors influencing mangrove establishment and survival during the Quaternary period are reviewed, focusing on research at latitudinal limits in Australia and mainland USA. Despite similarities in the response of mangrove to some drivers, the expression of these drivers is both spatially and temporally variable, demonstrating the need for analyses of mangrove-saltmarsh dynamics to move beyond generalizations and incorporate regional and …
Trilobite Extinctions, Facies Changes And The Roece Carbon Isotope Excursion At The Cambrian Series 2–3 Boundary, Great Basin, Western Usa, Luke E. Faggetter, Paul B. Wignall, Sara B. Pruss, Robert J. Newton, Yadong Sun, Stephen F. Crowley
Trilobite Extinctions, Facies Changes And The Roece Carbon Isotope Excursion At The Cambrian Series 2–3 Boundary, Great Basin, Western Usa, Luke E. Faggetter, Paul B. Wignall, Sara B. Pruss, Robert J. Newton, Yadong Sun, Stephen F. Crowley
Geosciences: Faculty Publications
The mass extinction of the olenellid trilobites occurred around the Cambrian Series 2–Series 3 boundary. Like many other crises, it coincided with a negative carbon isotope excursion but the associated palaeoenvironmental changes remain unclear. To investigate the causal mechanism for this event, we report facies changes, pyrite framboid petrography and carbon isotope values from Cambrian Series 2–Series 3 (traditionally Early–Middle Cambrian) boundary strata of the Carrara Formation (Death Valley region, California) and Pioche Formation (Nevada). These data reveal regionally changing water depths from high-energy, nearshore facies (oolitic grainstone) to more offshore silty marl and finer-grained carbonate mudstone. In the Carrara …
Examining The Use Of Amazon’S Mechanical Turk For Edge Extraction Of The Occlusal Surface Of Fossilized Bovid Teeth, George K. Thiruvathukal, Gregory J. Matthews, Maxwell P. Luetkemeier, Juliet K. Brophy
Examining The Use Of Amazon’S Mechanical Turk For Edge Extraction Of The Occlusal Surface Of Fossilized Bovid Teeth, George K. Thiruvathukal, Gregory J. Matthews, Maxwell P. Luetkemeier, Juliet K. Brophy
Computer Science: Faculty Publications and Other Works
In order to reconstruct environments associated with Plio-Pleistocene hominins in southern Africa, researchers frequently rely upon the animals associated with the hominins, in particular, animals in the Family Bovidae. Bovids in southern Africa are typically identified by their teeth. However, identifying the taxon of a bovid tooth is challenging due to various biasing factors. Furthermore, inaccurate identification of fossil bovids can have significant consequences on the reconstructed paleoenvironment. Recent research on the classification of bovid fossil teeth has relied on using elliptical Fourier analysis to summarize the shape of the outline of the occlusal surface of the tooth and the …
The Potential Effects Of Percolating Snowmelt On Palynological Records From Firn And Glacier Ice, Michael E. Ewin, Carl A. Reese, Matthew A. Nolan
The Potential Effects Of Percolating Snowmelt On Palynological Records From Firn And Glacier Ice, Michael E. Ewin, Carl A. Reese, Matthew A. Nolan
Faculty Publications
The effects of meltwater percolation on pollen in snow, firn and glacial ice are not fully understood and currently hamper the use of pollen in ice-core studies of paleoclimate. Several studies have suggested that, due to grain size, pollen is not mobilized by meltwater transport. However, these findings contradict many ice-core pollen studies that show pollen concentrations in snow and firn are much higher than concentrations found in the ice layers they eventually form. This study addresses one aspect of this question by investigating whether meltwater percolation can effectively transport pollen within a snowpack. We used nine Styrofoam coolers filled …
Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby
Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby
Adam Liska Papers
Many people tend to think that the outcome of any nuclear weapons use today will result in an escalatory situation with apocalyptic outcomes for the countries involved. Yet many factors are increasing the probability of the limited use of nuclear weapons (e.g., 1 to 20 warheads) in a range of conflict scenarios. Previous atmospheric model simulations of regional nuclear conflicts employing many relatively small bombs have been estimated to cause a global “nuclear autumn,” with great reductions in agricultural productivity, stratospheric ozone loss, and spread of hazardous radioactive fallout. The totality of these effects would result in widespread damage …
Volcanic Initiation Of The Eocene Heart Mountain Slide, Wyoming, Usa, Mark D. Schmitz
Volcanic Initiation Of The Eocene Heart Mountain Slide, Wyoming, Usa, Mark D. Schmitz
Geosciences Faculty Publications and Presentations
The Eocene Heart Mountain slide of northwest Wyoming covers an area of as much as 5000 km2 and includes allochthonous Paleozoic carbonate and Eocene volcanic rocks with a run-out distance of as much as 85 km. Recent geochronologic data indicated that the emplacement of the slide event occurred at ∼48.9 Ma, using laser ablation inductively coupled plasmamass spectrometry (LA-ICPMS) extracted fromU-Pb zircon ages frombasal layer and injectite carbonate ultracataclasite (CUC). We now refine that age with U-Pb results from a lamprophyre diatreme that is temporally and spatially related to the CUC injectites. The ages for the lamprophyre zircons are …
Epikarst Hydrogeochemical Changes In Telogenetic Karst Systems In South-Central Kentucky, Leah Jackson
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 …
Shower Atomization, Chirag Ayappa Ravishankar,
Shower Atomization, Chirag Ayappa Ravishankar,
Masters Theses & Specialist Projects
The research will help to design a shower for Dr. Chelson’s shelter, which can control the water flow, pressure and duration of the shower, which optimizes the utilization of water. The showers could be used in drought-hit areas where water is very scarce, as daily sanitation needs are necessary to keep a person safe and healthy without wasting water. The report from, World Health Organization shows that showers consume the most water. A timed shower could help resolve this issue through eliminating the wastage. Eco-friendly environmentalists may also be attracted to the showers, as their main purposes are to save …
Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Singer
Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Singer
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 secondary hydrogeochemical, …
Mesonets: Mesoscale Weather And Climate Observations For The United States, Rezaul Mahmood, Ryan Boyles, Kevin Brinson, Christopher Fiebrich, Stuart Foster, Ken Hubbard, David Robinson, Jeff Andresen, Dan Leathers
Mesonets: Mesoscale Weather And Climate Observations For The United States, Rezaul Mahmood, Ryan Boyles, Kevin Brinson, Christopher Fiebrich, Stuart Foster, Ken Hubbard, David Robinson, Jeff Andresen, Dan Leathers
High Plains Regional Climate Center: Staff Publications
Mesoscale in situ meteorological observations are essential for better understanding and forecasting the weather and climate and to aid in decision-making by a myriad of stakeholder communities. They include, for example, state environmental and emergency management agencies, the commercial sector, media, agriculture, and the general public. Over the last three decades, a number of mesoscale weather and climate observation networks have become operational. These networks are known as mesonets. Most are operated by universities and receive different levels of funding. It is important to communicate the current status and critical roles the mesonets play. Most mesonets collect standard meteorological data …
Nonmeteorological Influences On Severe Thunderstorm Warning Issuance: A Geographically Weighted Regression-Based Analysis Of County Warning Area Boundaries, Land Cover, And Demographic Variables, Megan L. White, J. Anthony Stallins
Nonmeteorological Influences On Severe Thunderstorm Warning Issuance: A Geographically Weighted Regression-Based Analysis Of County Warning Area Boundaries, Land Cover, And Demographic Variables, Megan L. White, J. Anthony Stallins
Geography Faculty Publications
Studies have shown that the spatial distribution of severe thunderstorm warnings demonstrates variation beyond what can be attributed to weather and climate alone. Investigating spatial patterns of these variations can provide insight into nonmeteorological factors that might lead forecasters to issue warnings. Geographically weighted regression was performed on a set of demographic and land cover descriptors to ascertain their relationships with National Weather Service (NWS) severe thunderstorm warning polygons issued by 36 NWS forecast offices in the central and southeastern United States from 2008 to 2015. County warning area (CWA) boundaries and cities were predominant sources of variability in warning …
Aeromagnetic And Spectral Expressions Of Rare Earth Element Deposits In Gallinas Mountains Area, Central New Mexico, Usa, Mo Li
Graduate Theses & Non-Theses
The Gallinas Mountains located in the conjunction of Lincoln County and Torrance County, New Mexico, USA are a series of alkaline volcanic rocks intruded into Permian sedimentary rocks. The Gallinas Mountains area is known to host fluorite and copper as veins containing bastnasite while hydrothermally altered rocks associated with iron oxides have been found in the area as well. In this study, multispectral band ratio method was used for surface mineral interpretation by processing satellite image, while aeromagnetic inversion method was applied using aeromagnetic data, digital elevation model and physical properties for 2-D subsurface structure modeling. Bastnasite has higher magnetic …
Evidence For Late Pliocene Deglacial Megafloods From Giant Sediment Waves In The Northern Gulf Of Mexico, Zexuan Wang
Evidence For Late Pliocene Deglacial Megafloods From Giant Sediment Waves In The Northern Gulf Of Mexico, Zexuan Wang
Masters Theses & Specialist Projects
Laurentide Ice Sheet outburst floods to the Gulf of Mexico have been mainly documented based on deep-sea cores, especially the megafloods, only during the last several interglacial episodes in the late Pleistocene. The paleoclimatic significance of giant sedimentary structures developed under unconfined Froude-supercritical turbidity currents in subaqueous settings is considerably under-examined. This research extensively documents >20-km-wide and 200-m-thick Plio-Pleistocene giant sediment waves for the first time on the northern Gulf of Mexico continental slope using 3D seismic data, which show waveform morphology in unprecedented detail. The results suggest that such large-scale bedforms were formed under sheet-like unconfined Froudesupercritical turbidity currents …
Genesis Of Schlottenkarren On The Avon Peninsula Of Nova Scotia (Canada) With Implications For The Geochronology Of Evaporite Karsts And Caves Of Atlantic Canada, Max Moseley
International Journal of Speleology
Exposed schlottenkarren karst terrains developed on gypsum-anhydrite evaporites in the Canadian Maritime provinces might be post-Glacial landscape features (formed on glacially-denuded rocks after they are uncovered by progressive erosion of overlying glacial tills) or exhumed pre-Last Glacial Maximum (LGM) morphologies (filled with glacial till and revealed by erosion of the tills). In this paper the hydrological conditions necessary for the formation of schlottenkarren, the speleogenetic processes involved and their chronology are reconsidered and reinterpreted. It is proposed that they are essentially pre-LGM features which have survived from the Wisconsinan. It is concluded that the degree of glacial scouring and denudation …
Characterizing Benthic Habitats Using Multibeam Sonar And Towed Underwater Video In Two Marine Protected Areas On The West Florida Shelf, Usa, Jennifer L. Brizzolara
Characterizing Benthic Habitats Using Multibeam Sonar And Towed Underwater Video In Two Marine Protected Areas On The West Florida Shelf, Usa, Jennifer L. Brizzolara
USF Tampa Graduate Theses and Dissertations
This study investigates a way to characterize the geology and biology of the seafloor in two Marine Protected Areas on the West Florida Shelf. Characterization of benthic habitats needs to include sufficient detail to represent the complex and heterogeneous bottom types. Characterizations can be interpreted from multiple data sets and displayed as benthic habitat maps. Multibeam sonar bathymetry and backscatter provide full spatial data coverage, but interpretation of such data requires some form of ground truth (to characterize the habitat). Imagery from towed underwater video provides continuous transects of seafloor data, which provide a more efficient method than data from …
Analyzing Dam Feasibility In The Willamette River Watershed, Alexander Cameron Nagel
Analyzing Dam Feasibility In The Willamette River Watershed, Alexander Cameron Nagel
Dissertations and Theses
This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top …
The Place Toolkit: Exposing Geospatial Ready Digital Collections, Eleta Exline, Hannah Hamalainen, Michael Routhier, Val Harper, Place Project Group
The Place Toolkit: Exposing Geospatial Ready Digital Collections, Eleta Exline, Hannah Hamalainen, Michael Routhier, Val Harper, Place Project Group
PLACE Project
PLACE, the Position-based Library Archive Coordinate Explorer, is a University of New Hampshire geospatial data server and search interface that enables discovery of digital collections. Identifying geographic coordinates for “geospatial ready” digitized cultural heritage materials is key to the project.
Presented: Open Repositories 2017, Brisbane, Australia. June 27, 2017
Aerodynamic Roughness Length Estimation With Lidar And Imaging Spectroscopy In A Shrub-Dominated Dryland, Aihua Li, Wenguang Zhao, Jessica J. Mitchell, Nancy F. Glenn, Matthew J. Germino, Joel B. Sankey, Richard G. Allen
Aerodynamic Roughness Length Estimation With Lidar And Imaging Spectroscopy In A Shrub-Dominated Dryland, Aihua Li, Wenguang Zhao, Jessica J. Mitchell, Nancy F. Glenn, Matthew J. Germino, Joel B. Sankey, Richard G. Allen
Geosciences Faculty Publications and Presentations
The aerodynamic roughness length (Z0m) serves an important role in the flux exchange between the land surface and atmosphere. In this study, airborne lidar (ALS), terrestrial lidar (TLS), and imaging spectroscopy data were integrated to develop and test two approaches to estimate Z0m over a shrub dominated dryland study area in south-central Idaho, USA. Sensitivity of the two parameterization methods to estimate Z0m was analyzed. The comparison of eddy covariance-derived Z0m and remote sensing-derived Z0m showed that the accuracy of the estimated Z0m heavily depends on the estimation model and the representation of …
Facies Architecture And Provenance Of A Boulder-Conglomerate Submarine Channel System, Panoche Formation, Great Valley Group: A Forearc Basin Response To Middle Cretaceous Tectonism In The California Convergent Margin, T. J. Greene, Kathleen D. Surpless
Facies Architecture And Provenance Of A Boulder-Conglomerate Submarine Channel System, Panoche Formation, Great Valley Group: A Forearc Basin Response To Middle Cretaceous Tectonism In The California Convergent Margin, T. J. Greene, Kathleen D. Surpless
Earth and Environmental Geosciences Faculty Research
Tectonic reorganization induced by a rapid increase in plate motion obliquity and rate beginning at ca. 100 Ma affected California’s Andean-style convergent margin, with concomitant changes in the accretionary prism of the Franciscan Complex, the Great Valley forearc basin, and the Sierran continental arc. Using facies analysis and a combined provenance approach, we suggest that this ca. 100 Ma tectonic signal is preserved in a Cenomanian (Upper Cretaceous) boulder-conglomerate outcrop along the San Luis Reservoir (SLR) in the southern Great Valley, which represents the thickest and coarsest deep-water deposit ever described in the Great Valley Group (GVG). We document a …