Designing A Protected Area To Safeguard Imperiled Species From Urbanization,
2018
U.S. Geological Survey, Wetland and Aquatic Research Center
Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson
United States Geological Survey: Staff Publications
Reserve design is a process that can address ecological, social, and political factors to identify parcels of land needed to sustain wildlife populations and other natural resources. Acquisition of parcels for a large terrestrial reserve is difficult because it typically occurs over a long timeframe and thus invokes consideration of future conditions such as climate and urbanization changes. In central Florida, the U.S. government has authorized a new protected area, the Everglades Headwaters National Wildlife Refuge. The new refuge will host important threatened and endangered species and habitats, and will be located to allow for species adaptation from climate change …
Assessing Ground Penetrating Radar's Ability To Image Subsurface Characteristics Of Icy Debris Fans In Alaska And New Zealand,
2018
Bucknell University
Assessing Ground Penetrating Radar's Ability To Image Subsurface Characteristics Of Icy Debris Fans In Alaska And New Zealand, Robert W. Jacob, Jeffrey M. Trop, R. Craig Kochel
Faculty Journal Articles
Icy debris fans have recently been described as fan shaped depositional landforms associated with (or formed during) deglaciation, however, the subsurface characteristics remain essentially undocumented. We used ground penetrating radar (GPR) to non-invasively investigate the subsurface characteristics of icy debris fans (IDFs) at McCarthy Glacier, Alaska, USA and at La Perouse Glacier, South Island of New Zealand. IDFs are largely unexplored paraglacial landforms in deglaciating alpine regions at the mouths of bedrock catchments between valley glaciers and icecaps. IDFs receive deposits of mainly ice and minor lithic material through different mass-flow processes, chiefly ice avalanche and to a lesser extent …
Discovery Of Paleotsunami Deposits Along Eastern Sunda Arc: Potential For Megathrust Earthquakes In Bali,
2018
Brigham Young University
Discovery Of Paleotsunami Deposits Along Eastern Sunda Arc: Potential For Megathrust Earthquakes In Bali, Hanif Ibadurrahman Sulaeman
Theses and Dissertations
Several laterally extensive candidate tsunami deposits are preserved along coastlines facing the eastern Java Trench, indicating it has experienced mega-thrust earthquakes in the past. We investigated 37 coastal sites in Bali, Lombok, Sumba and Timor islands, many of which preserve course sand and pebble layers that overlie sharp basal contacts with scour marks into the mud, fine upward in grain size, and have bimodal grain size distributions. Other unique features are the common occurrence of marine fossils and concentrations of heavy minerals. The occurrence of these high-energy deposits interlayered with clay-rich units indicates the coarse clastics are anomalous because they …
Diamond Intracrystalline Stable Isotope Chemical Image Analysis By Time-Of-Flight Secondary Ionization Mass Spectrometery,
2018
Missouri State University
Diamond Intracrystalline Stable Isotope Chemical Image Analysis By Time-Of-Flight Secondary Ionization Mass Spectrometery, Tyler J. Sundell
Graduate Theses/Dissertations
The chemical resistance of diamond allows in-situ study of the diamond source regions. For a majority of gem quality diamonds, this source region is the sublithospheric mantle keel of a cratonic nuclei. Through analysis of stable isotopes, radiogenic isotopes and trace elements, diamond geochemical analyses can define chemical fluxes in the mantle keel. However, such studies require multiple methodologies for each chemical suite, high spatial resolution and analytical precision. Here, I evaluate Time-of-Flight Secondary Ionization Mass Spectrometer (ToF-SIMS) as an alternative method for diamond geochemical analyses. ToF-SIMS analysis can perform in cation and anion mode to measure the entire periodic …
The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults,
2018
Utah State University
The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Our current understanding of thrust fault kinematics predicts that thrust faults nucleate on low angle, weak surfaces before they propagate upward and forms a higher angle ramp. While this classic kinematic and geometric model serves well in some settings, it does not fully consider the observations of footwall deformation beneath some thrust faults. We examine an alternative end-member model of thrust fault formation called “ramp-first” fault formation. This model hypothesizes that in mechanically layered rocks, thrust ramps nucleate in the structurally strong units, and that faults can propagate both upward and downward into weaker units forming folds at both fault …
Receiver Function Investigations Of Seismic Anisotropy Layering Beneath Southern California,
2018
Missouri University of Science and Technology
Receiver Function Investigations Of Seismic Anisotropy Layering Beneath Southern California, Fansheng Kong, Stephen S. Gao, Kelly H. Liu, Jianguo Song, Weiwei Ding, Yinxia Fang, Aiguo Ruan, Jiabiao Li
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Seismic azimuthal anisotropy characterized by shear wave splitting analyses using tele seismic XKS phases (including SKS, SKKS, and PKS) is widely employed to constrain the deformation field in the Earth's crust and mantle. Due to the near-vertical incidence of the XKS arrivals, the resulting splitting parameters (fast polarization orientations and splitting times) have an excellent horizontal but poor vertical resolution, resulting in considerable ambiguities in the geodynamic interpretation of the measurements. Here we use P-to-S converted phases from the Moho and the 410- (d410) and 660-km (d660) discontinuities to investigate anisotropy layering beneath Southern California. Similarities between the resulting splitting …
Physical And Chemical Controls On Suffosion Development In Gypsic Soil, Culberson County, Texas,
2018
Stephen F. Austin State University
Physical And Chemical Controls On Suffosion Development In Gypsic Soil, Culberson County, Texas, Jonah Morris
Electronic Theses and Dissertations
In the Gypsum Plain, suffosion processes have encouraged road failure through dissolution and transport of gypsic soils; however, no prior research has been conducted within the Delaware Basin in regard to these processes. These phenomena were evaluated in both field and laboratory settings in order to assess the parameters of suffosion development associated with Ranch to Market (RM) 652 in Culberson County, Texas, where infrastructure extends across Castile and Rustler strata. Field studies simulated surficial ponding in various gypsic soils and correlated suffosion potential with soil composition and thickness. Soluble fractions of gypsic soils were delineated through geochemical analyses, further …
Depositional Environment And Facies Analyses Of The Owl Mountain Province, Fort Hood Military Installation, Bell And Coryell Counties, Texas,
2018
Stephen F. Austin State University
Depositional Environment And Facies Analyses Of The Owl Mountain Province, Fort Hood Military Installation, Bell And Coryell Counties, Texas, Jacob Meinerts
Electronic Theses and Dissertations
The Owl Mountain Province is a plateaued, karst landscape located in the eastern section of the Fort Hood Military Installation and is characterized by Lower Cretaceous Fredericksburg Group carbonates. The topography is capped by thick sequences of the Edwards limestone; steep scarps and incised valleys along the edges of the plateaus host inter-fingering outcrops of the Edwards and Comanche Peak limestones, and the lower valleys are covered by alluvial sediments and intermittent outcrops of the Walnut Clay. These formations were deposited to the north and west of the main Edwards trend, and are thought to be part of a series …
An Outcrop Based Study Of The Weches Formation In Sabine County, Texas: Investigating Its Unconventional Resource Potential Through The Study Of Stratigraphy, Sedimentology, Petrology, And Geochemistry,
2018
Stephen F Austin State University
An Outcrop Based Study Of The Weches Formation In Sabine County, Texas: Investigating Its Unconventional Resource Potential Through The Study Of Stratigraphy, Sedimentology, Petrology, And Geochemistry, Talban Kantala
Electronic Theses and Dissertations
Fresh Weches Formation (Middle Eocene) exposures found in aggregate quarries in Sabine County, Texas, were sampled, measured, and logged with gamma-ray spectrometry (GRS). Sedimentology and petrology characteristics of Weches samples were analyzed through thin section, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and GRS Th/K ratios analyses. The source rock quality of the Weches was evaluated with geochemical techniques involving total organic carbon (TOC), Rock-Eval pyrolysis, and GRS Th/U ratios.
The Weches, in the study area, is 27.4 meters thick, and delineated into three major stratigraphic facies: an upper marginal marine prodeltaic facies (Therrill Member) comprised of silty claystones and …
An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma,
2018
University of Arkansas, Fayetteville
An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma, Abram Max Barker
Graduate Theses and Dissertations
Integrated analysis of well and geophysical data can provide detailed geologic interpretation of the subsurface in Osage County, Oklahoma. Systems tracts and depositional system successions can be interpreted at marginal seismic resolution using well log motif with seismic reflector character within a depositional context. Shelf-prism and subaqueous, delta-scale clinoforms of Missourian age observed in 3D seismic were interpreted with greater sequence stratigraphic detail when coupled with wireline well logs. The Late Pennsylvanian Midcontinent Sea was thought to be approximately 150 feet average depth across the southern Midcontinent during the Missourian Stage, and deepen towards the Arkoma and Anadarko Basins to …
Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina,
2018
Boise State University
Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler
Boise State University Theses and Dissertations
Stable isotope analysis has become the method of choice for many studies investigating the paleoecology and paleoclimate of fossil mammal faunas. While organic tissues (collagen, keratins, proteins) persist for < 105 years highly mineralized tooth enamel is resistant to alteration and degradation and faithfully preserves its isotopic composition for millions (> 106) years. Reconstructing past climates from these records relies on both understanding both micro-scale mechanisms of isotope incorporation into individual teeth, and macro-scale changes in isotope compositions over hundreds of thousands or millions of years. In this dissertation I address three questions.
First, how does the geometry and …
Exploring Potential Water-Ice Occurrence On Asteroid 4 Vesta Using Orbital Radar Observations By The Dawn Mission,
2018
Western Michigan University
Exploring Potential Water-Ice Occurrence On Asteroid 4 Vesta Using Orbital Radar Observations By The Dawn Mission, Elizabeth M. Palmer
Dissertations
Airless, differentiated planetesimals in the inner solar system were presumed to have been depleted of most of their initial volatile content during formation. However, water-ice has been discovered at the lunar poles (Li et al., 2018), is inferred to exist in polar craters on Mercury (e.g., Butler, Slade & Muhleman, 1993, and suggested to survive beneath the dusty regolith of objects in the main asteroid belt if buried at sufficient depths—at least one meter for small-bodies in the outer main-belt (Schorghofer, 2008). Hence, the study of volatile occurrence, past or present, on airless, desiccated small-bodies provides insights into the timing, …
Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives,
2018
University of Southern Mississippi
Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar
Dissertations
Robert Parker (1972) demonstrated the effectiveness of Fourier Transforms (FT) to compute gravitational potential anomalies caused by uneven, non-uniform layers of material. This important calculation relates the gravitational potential anomaly to sea-floor topography. As outlined by Sandwell and Smith (1997), a six-step procedure, utilizing the FT, then demonstrated how satellite altimetry measurements of marine geoid height are inverted into seafloor topography. However, FTs are not local in space and produce Gibb’s phenomenon around discontinuities. Seafloor features exhibit spatial locality and features such as seamounts and ridges often have sharp inclines. Initial tests compared the windowed-FT to wavelets in reconstruction of …
Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas,
2018
University of Arkansas, Fayetteville
Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham
Graduate Theses and Dissertations
The Arkoma Basin is a Carboniferous peripheral foreland basin creating a structural depression covering an approximate area of 33,800 miles2 that extends through east-central Oklahoma and west-central Arkansas. The entire basin fill includes Pre-Mississippian carbonate shelf deposits, Mississippian marine carbonates and black shales, and Pennsylvanian mixed carbonated/clastic and shore zone/deltaic deposits. The Lower Atoka formation (Pennsylvanian) occurs in outcrop along the southern Boston Mountain Plateau in northern Arkansas and extends into the subsurface of the Arkoma Basin over an area of 2,300 miles2. The Lower Atoka ranges from 600 to 1500 feet in thickness and represents a cyclic succession of …
Hydrogeologic Framework Studies Of Portions Of The Niobrara River,
2018
University of Nebraska - Lincoln
Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard
Conservation and Survey Division: Faculty and Staff Publications
The Nebraska Department of Natural Resources (NeDNR) and Upper Niobrara-White Natural Resources District (UNWNRD) expressed interest in improving understanding and their ability to effectively manage water resources in and around a particular reach of the Niobrara River. Aquifer-thickness contours mapped by the Conservation and Survey Division (CSD) indicate that the principle aquifer has zero thickness in this area. Additionally, the statewide geologic bedrock map produced by CSD shows non-aquifer strata of the White River Group along the same reach, and this setting is consistent with the designation of an “aquifer absent area,” as in the present document. Water-management policy development …
Improving Sinkhole Mapping Using Lidar Data And Locating Sinkhole Hotspots In Johnson City, Tn,
2018
East Tennessee State University
Improving Sinkhole Mapping Using Lidar Data And Locating Sinkhole Hotspots In Johnson City, Tn, Kingsley Fasesin
Electronic Theses and Dissertations
Predicting infrastructure damage and economic impact of sinkholes requires high accuracy mapping distribution and development. The study mapped sinkholes and sinkhole hotpsots in Johnson City, TN using LiDAR-derived Digital Elevation Model (DEM) and a database of known sinkholes which were matched to LiDAR-derived depressions. For all matched depressions (n = 404), three metrics were calculated: circularity index, ratio of length to width of the Minimum Bounding Rectangle (MBR) and percent coverage of the MBR by the depression, and 3,634 new sinkholes were identified. Newly developed hotspots were identified in north Johnson City and other areas in the south near the …
Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy).,
2018
University of Warsaw
Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński
EKU Faculty and Staff Scholarship
The Green Tuff Ignimbrite, Pantelleria, is compositionally zoned from pantellerite at the base to comenditic trachyte at the top, the variation apparently representing an inverted vertical zonation in the pre-eruptive reservoir. The main phenocryst assemblages are alkali feldspar + olivine + clinopyroxene + ilmenite + apatite in the trachytes and alkali feldspar + aenigmatite + clinopyroxene + quartz in the rhyolites. Thermodynamic modelling indicates that the temperature range was ~900–700°C, fO2 FMQ –1.5 to FMQ –0.5 (where FMQ is fayalite–magnetite–quartz buffer) and aSiO2 (relative to quartz saturation) 0.74–1.00. Melt water contents ranged from ~1wt % in the trachytes to ~4wt …
New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States,
2018
Utah State University
New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States, Abigail R. Bullard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Three related sedimentary successions located in Arizona, Utah, and California were deposited in basins on proto-North America during the early rifting of Rodinia (~780 Mya). Previous detrital zircon U-Pb maximum ages for the units are inexact, making it difficult to piece together what happened at this point in Earth history.
We report better maximum age constraints on these units obtained by subjecting detrital zircons to high-precision CA-ID-TIMS analysis, which provide more exact 206Pb/238U ages. These new data significantly improve the precision for the base of the ChUMP units, with an average age of 775.63 ± 0.27 Ma …
Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa,
2018
University of Southern Mississippi
Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis
Master's Theses
Coastal systems in the Gulf of Mexico are threatened to reduced sediment supply, storm impacts and relative sea level rise (RSLR). The geologic record can provide insights of geomorphic threshold crossings (formation, progradation, transgression, destruction) to these forcing mechanisms to predict future barrier evolution to climate change. The stratigraphic framework and antecedent topography directly influence coastal evolution over geologic timescales. This study synthesizes ~2100km of geophysical data, 700+ sediment cores, and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 x10 …
Holocene Formation And Evolution Of Horn Island, Mississippi, Usa,
2018
University of Southern Mississippi
Holocene Formation And Evolution Of Horn Island, Mississippi, Usa, Nina Gal
Master's Theses
Horn Island, one of the most stable barriers along the Mississippi-Alabama chain, provides critical habitat, helps regulate estuarine conditions in the Mississippi Sound, and reduces wave energy and storm surge for the mainland. This study integrates 2,200 km of high-resolution geophysics, 35 sediment cores, and 15 radiocarbon ages to better understand the formation and evolution of the island in response to sea-level rise, storms, and antecedent geology. The Biloxi and Pascagoula incised valleys converge at Horn Island and have played a profound role in the evolution of the system. Within the incised valleys, numerous shallow paleochannels between 4 and 9 …
