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The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler 2017 University of Southern Mississippi

The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler

Master's Theses

Fe-Ti oxides are important components of oceanic core complexes (OCC) formed at slow-spreading mid-ocean ridges since Fe-Ti oxides are more susceptible to crystal-plastic deformation than silicate minerals. This study investigated the predicted relationship between the presence and concentration of Fe-Ti oxides and the presence and intensity of crystal-plastic deformation in gabbroic samples from Atlantis Bank, Southwest Indian Ridge (SWIR). Atlantis Bank is an oceanic core complex that formed through the exhumation of lower oceanic crust along a detachment fault. OCCs form along slow-spreading ridges and are characterized by the complex interactions between magmatism and lithospheric extension, thus making these complexes ...


The Utility Of Foraminifera In Documenting Sediment Provenance For Overwash Deposits: A Case Study Using Sediments Deposited By Tropical Cyclone Pam In Vanuatu, thomas kosciuch 2017 The University of Southern Mississippi

The Utility Of Foraminifera In Documenting Sediment Provenance For Overwash Deposits: A Case Study Using Sediments Deposited By Tropical Cyclone Pam In Vanuatu, Thomas Kosciuch

Master's Theses

Tropical cyclone inundation is a major threat to the highly exposed islands of the South Pacific. This vulnerability was highlighted in March 2015 when Tropical Cyclone (TC) Pam made landfall on Vanuatu as a Category 5 storm, impacting coastlines with storm surges that produced high water marks up to 7 m above MSL and deposited sediments up to 400 m inland. We examined the foraminiferal assemblages contained within TC Pam sediments at two locations in Vanuatu: a mixed-carbonate embayment (Manuro), and a volcaniclastic beach (Port Resolution Bay; PRB). At Manuro, the TC Pam sediments were up to 10 cm thick ...


De Paepe, Duane - Collector (Mss 625), Manuscripts & Folklife Archives 2017 Western Kentucky University

De Paepe, Duane - Collector (Mss 625), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Collection 625. The Duane De Paepe Kentucky Cave Saltpetre History Research Collection, a collection of historical research, field notes, cave surveys, photographs, maps, reports, and scholarly writing on saltpetre mining in Kentucky, especially at Mammoth Cave. The collection was created under a research program sponsored by the Cave Research Foundation and the National Geographic Society in Kentucky, 1976-1980, and directed by De Paepe.


A Prograding Margin During Global Sea-Level Maxima: An Example From Mahajanga Basin, Northwest Madagascar, Jonathan Obrist-Farner, Philip J. Ball, Thomas A. (Mac) McGilvery, Raymond R. Rogers 2017 Missouri University of Science and Technology

A Prograding Margin During Global Sea-Level Maxima: An Example From Mahajanga Basin, Northwest Madagascar, Jonathan Obrist-Farner, Philip J. Ball, Thomas A. (Mac) Mcgilvery, Raymond R. Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Mesozoic shelf margin in the Mahajanga Basin, northwest Madagascar, provides an example where inherited palaeobathymetry, coupled with sea-level changes, high sediment supply and fluctuations in accommodation influenced the stacking patterns and geometry of clinoforms that accreted onto a passive rifted margin. Two-dimensional (2D) seismic profiles are integrated with existing field data and geological maps to study the evolution of the margin. The basin contains complete records of transgression, highstand, regression and lowstand phases that took place from Jurassic to Cretaceous. Of particular interest is the Cretaceous, Albian to Turonian (ca. 113-93 Ma), siliciclastic shelf margin that prograded above a ...


A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib 2017 Missouri University of Science and Technology

A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib

David M. Borrok

Water of poor quality can directly impact the budget of water available for key user groups. Despite this importance, methods for quantifying the impact of water quality on water availability remain elusive. Here, we develop a new framework for incorporating the impact of water quality on water supply by modifying the Water Supply Stress Index (WaSSI). We demonstrate the usefulness of the framework by investigating the impact of high salinity waters on the availability of irrigation water for agriculture in Louisiana. The WaSSI was deconstructed into sectoral components such that the total available water supply could be reduced for a ...


Seismic Azimuthal Anisotropy Beneath The Eastern United States And Its Geodynamic Implications, Bin B. Yang, Yunhua Liu, Haider Dahm, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Seismic Azimuthal Anisotropy Beneath The Eastern United States And Its Geodynamic Implications, Bin B. Yang, Yunhua Liu, Haider Dahm, Kelly H. Liu, Stephen S. Gao

Stephen S. Gao

Systematic spatial variations of anisotropic characteristics are revealed beneath the eastern U.S. using seismic data recorded between 1988 and 2016 by 785 stations. The resulting fast polarization orientations of the 5613 measurements are generally subparallel to the absolute plate motion (APM) and are inconsistent with the strike of major tectonic features. This inconsistency, together with the results of depth estimation using the spatial coherency of the splitting parameters, suggests a mostly asthenospheric origin of the observed azimuthal anisotropy. The observations can be explained by a combined effect of APM-induced mantle fabric and a flow system deflected horizontally around the ...


Seismic Anisotropy Beneath The Afar Depression And Adjacent Areas: Implications For Mantle Flow, Stephen S. Gao, Kelly H. Liu, Mohammed G. Abdel Salam 2017 Missouri University of Science and Technology

Seismic Anisotropy Beneath The Afar Depression And Adjacent Areas: Implications For Mantle Flow, Stephen S. Gao, Kelly H. Liu, Mohammed G. Abdel Salam

Stephen S. Gao

Shear wave splitting is a robust tool to infer the direction and strength of seismic anisotropy in the lithosphere and underlying asthenosphere. Previous shear wave splitting studies in the Afar Depression and adjacent areas concluded that either Precambrian sutures or vertical magmatic dikes are mostly responsible for the observed anisotropy. Here we report results of a systematic analysis of teleseismic shear wave splitting using all the available broadband seismic data recorded in the Afar Depression, Main Ethiopian Rift (MER), and Ethiopian Plateau. We found that while the ~450 measurements on the Ethiopian Plateau and in the MER show insignificant azimuthal ...


Spatial Variations Of Crustal Characteristics Beneath The Hoggar Swell, Algeria, Revealed By Systematic Analyses Of Receiver Functions From A Single Seismic Station, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Spatial Variations Of Crustal Characteristics Beneath The Hoggar Swell, Algeria, Revealed By Systematic Analyses Of Receiver Functions From A Single Seismic Station, Kelly H. Liu, Stephen S. Gao

Stephen S. Gao

The Hoggar swell in Algeria is one of the significant massifs of northwest Africa. The paucity of high-resolution geophysical studies of the crust and mantle beneath the massifs is mostly responsible for the heated debates about the depth of the source region of the Cenozoic volcanism and the closely related uncertainty about the mechanism that formed and maintains the high elevation of the swells. Here we report results from a systematic study of 1386 high-quality receiver functions (RFs) recorded by station TAM, the only permanent broadband seismic station on the Hoggar swell. The resulting crustal thickness is about 34 km ...


Reply [To “Comment On “Sks Splitting Beneath Continental Rifts Zones” By Gao Et Al.”], Stephen S. Gao, Paul M. Davis, Kelly H. Liu, Philip D. Slack, Andrew W. Rigor, Yu A. Zorin, Valentina V. Mordvinova, Vladimir M. Kozhevnikov, Nikolai A. Logatchev 2017 Missouri University of Science and Technology

Reply [To “Comment On “Sks Splitting Beneath Continental Rifts Zones” By Gao Et Al.”], Stephen S. Gao, Paul M. Davis, Kelly H. Liu, Philip D. Slack, Andrew W. Rigor, Yu A. Zorin, Valentina V. Mordvinova, Vladimir M. Kozhevnikov, Nikolai A. Logatchev

Stephen S. Gao

No abstract provided.


Making Reliable Shear-Wave Splitting Measurements, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Making Reliable Shear-Wave Splitting Measurements, Kelly H. Liu, Stephen S. Gao

Stephen S. Gao

Shear-wave splitting (SWS) analysis using SKS, SKKS, and PKS (hereafter collectively called XKS) phases is one of the most commonly used techniques in structural seismology. In spite of the apparent simplicity in performing SWS measurements, large discrepancies in published SWS parameters (fast direction and splitting time) suggest that a significant portion of splitting parameters has been incorrectly determined. Here, based on the popularly used minimization of transverse energy technique, we present a procedure that combines automatic data processing and careful manual screening, which includes adjusting the XKS window used for splitting analysis, modifying band-pass filtering corner frequencies, and verifying and ...


A Bayesian Nonlinear Inversion Of Seismic Body-Wave Attenuation Factors, Stephen S. Gao 2017 Missouri University of Science and Technology

A Bayesian Nonlinear Inversion Of Seismic Body-Wave Attenuation Factors, Stephen S. Gao

Stephen S. Gao

It is a well-known fact that the uncertainties in measuring relative attenuation factors within a local or regional seismic network are usually high, due to noise of different kinds and unrealistic assumptions. Numerical experiments using nine synthetic seismograms, created using t* values ranging from 0.1 to 0.9 sec, reveal that the commonly used spectral ratio method is strongly affected by the selection of data processing parameters such as width of the spectral smoothing window, reference station, and so on. The numerical experiments demonstrate that a Bayesian nonlinear inversion approach that directly matches the spectra is better at finding ...


Estimation Of The Depth Of Anisotropy Using Spatial Coherency Of Shear-Wave Splitting Parameters, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Estimation Of The Depth Of Anisotropy Using Spatial Coherency Of Shear-Wave Splitting Parameters, Kelly H. Liu, Stephen S. Gao

Stephen S. Gao

Shear-wave splitting (SWS) analyses are essential in understanding the structure and dynamics of the Earth's deep interior. While splitting measurements have excellent horizontal resolution relative to other anisotropy-measuring techniques, their vertical resolution is low due to the steep incidence angle of the seismic phases used by the analyses. Here, using synthetic and real data, we present and test a simple approach to estimate the optimal depth of anisotropy by measuring the spatial coherency of the splitting parameters. The approach searches for the optimal depth by computing a spatial variation factor. Tests using synthetic SWS data produced with varying number ...


Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives 2017 Western Kentucky University

Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Collection 620. Correspondence, research notes, drafts, photographs, reference works and bibliographic material of Burton S. Faust relating to his studies of the chemical, historical and cultural aspects of saltpetre and of spelean saltpetre mining in the United States.


Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet 2017 Murray State University

Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet

Posters-at-the-Capitol

Assessing the Periodic Groundwater Flow Conditions of a Perched Aquifer System in the Daniel Boone National Forest

Ethan Sweet and Jonathan Malzone

Eastern Kentucky University, Department of Geosciences

Natural ephemeral wetlands situated among the ridge-tops in the Daniel Boone National Forest serve as reservoirs that recharge a shallow groundwater system. Unique interactions between surface and groundwater in these isolated systems provide substantial support for the native ecosystem, serving as a breeding ground for amphibians and as source water for vegetation—especially in periods of drought. Currently it is not understood how groundwater could provide regional biodiversity, a drought buffer, or ...


A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin 2017 California Polytechnic State University, San Luis Obispo

A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin

Natural Resources Management and Environmental Sciences

Marine terrace formation is in many instances attributed to wave action, and shore platforms are often called “wave-cut”. However, alternative models for marine terrace formation suggest that other types of physical and chemical weathering have a more central role in the formation of marine terraces than is widely acknowledged. Roering and Retallack (2012) concluded that the roles of subaerial physical and chemical weathering are significant, and played a major role in the formation of the terraces. In this study, weathering of beach cliffs and shore platforms associated with marine terraces at eight sites in two different locations along the central ...


An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon 2017 Fort Hays State University

An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon

Master's Theses

Subsurface mapping from well points and 3D seismic interpretation are essential techniques used to study and locate structures in petroleum exploration. In this study, subsurface structure maps, detailed well log facies analysis, 3D seismic interpretation, and attribute analysis were used to map a Mississippian interval and middle Pennsylvanian age interval from two oil fields in Ness County, Kansas. The objective of this study is to analyze formation properties and facies distribution, map middle Pennsylvanian Cherokee channel deposits using seismic data, and to construct a structural model highlighting important features effecting oil production. Results show that the stratigraphic succession of this ...


A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib 2017 Missouri University of Science and Technology

A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Water of poor quality can directly impact the budget of water available for key user groups. Despite this importance, methods for quantifying the impact of water quality on water availability remain elusive. Here, we develop a new framework for incorporating the impact of water quality on water supply by modifying the Water Supply Stress Index (WaSSI). We demonstrate the usefulness of the framework by investigating the impact of high salinity waters on the availability of irrigation water for agriculture in Louisiana. The WaSSI was deconstructed into sectoral components such that the total available water supply could be reduced for a ...


Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl 2017 Norwegian Institute of Air Research

Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl

William I. Rose

Uncertainty in the physicochemical and optical properties of volcanic ash particles creates errors in the detection and modeling of volcanic ash clouds and in quantification of their potential impacts. In this study, we provide a data set that describes the physicochemical and optical properties of a representative selection of volcanic ash samples from nine different volcanic eruptions covering a wide range of silica contents (50–80 wt % SiO2). We measured and calculated parameters describing the physical (size distribution, complex shape, and dense-rock equivalent mass density), chemical (bulk and surface composition), and optical (complex refractive index from ultraviolet to near-infrared ...


Martian Cave Air-Movement Via Helmholtz Resonance, Kaj E. Williams, Timothy N. Titus, Chris H. Okubo, Glen E. Cushing 2017 U.S. Geological Survey

Martian Cave Air-Movement Via Helmholtz Resonance, Kaj E. Williams, Timothy N. Titus, Chris H. Okubo, Glen E. Cushing

International Journal of Speleology

Infrasonic resonance has previously been measured in terrestrial caves by other researchers, where Helmholtz resonance has been suggested as the plausible mechanism resulting in periodic wind reversals within cave entrances. We extend this reasoning to possible Martian caves, where we examine the characteristics of four atypical pit craters (APCs) on Tharsis, suggested as candidate cave entrance locations. The results show that, for several possible cave air movement periods, we are able to infer the approximate cave volumes. The utility of inferring cave volumes for planetary cave exploration is discussed.


C1: Applying The Cosmogenic Nuclide Dipstick Model For Deglaciation Of Mt. Washington, P. Thompson Davis, Alexandria J. Koester, Jeremy D. Shakun, Paul R. Bierman, Lee B. Corbett 2017 Bentley University

C1: Applying The Cosmogenic Nuclide Dipstick Model For Deglaciation Of Mt. Washington, P. Thompson Davis, Alexandria J. Koester, Jeremy D. Shakun, Paul R. Bierman, Lee B. Corbett

New England Intercollegiate Geological Conference 2017

Guidebook for field trips in Western Maine and Northern New Hampshire: New England Intercollegiate Geological Conference, p. 247-272.


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