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Geology

Missouri University of Science and Technology

2016

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Articles 1 - 30 of 31

Full-Text Articles in Physical Sciences and Mathematics

An Assessment Of Concrete Over Asphalt Pavement Using Both The Ultrasonic Surface Wave And Impact Echo Techniques, Mengxing Li, Neil Lennart Anderson, Lesley Sneed, Xin Kang Dec 2016

An Assessment Of Concrete Over Asphalt Pavement Using Both The Ultrasonic Surface Wave And Impact Echo Techniques, Mengxing Li, Neil Lennart Anderson, Lesley Sneed, Xin Kang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A portable seismic property analyzer (PSPA) was used to simultaneously acquire both ultrasonic surface wave (PSPA-USW) and impact-echo (PSPA-IE) data at predetermined locations along a section of multi-layered pavement. The pavement consisted of a basal concrete layer (~220 mm), an intervening layer of hot-mix asphalt (~60 mm), and a concrete overlay (~220 mm). The section of multi-layered pavement was cored at multiple PSPA test locations for verification purposes. The conditions of the extracted cores were assessed visually, and the static elastic modulus, as well as the compressional wave velocity of each concrete overlay core, were measured in the laboratory. Results …


Small-Scale Catchment Analysis Of Water Stress In Wet Regions Of The U.S.: An Example From Louisiana, Hisham Eldardiry, Emad H. Habib, David M. Borrok Dec 2016

Small-Scale Catchment Analysis Of Water Stress In Wet Regions Of The U.S.: An Example From Louisiana, Hisham Eldardiry, Emad H. Habib, David M. Borrok

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Groundwater is increasingly being overdrafted in the Southeastern U.S., despite abundant rainfall and the apparent availability of surface water. Using the state of Louisiana as an example, the current study quantifies the stresses on water resources and investigates the potential for opportunities to use surface water in lieu of groundwater pumping. The assessment is based on a fine watershed scale (12-digit Hydrological Unit Code [HUC] boundaries) water balance between the availability of surface and groundwater and surface water and groundwater demand. Water demand includes environmental flows, as well as public supply, rural domestic, industrial, power generation, agricultural, and aquaculture sectors. …


Ground-Penetrating Radar Water Content Mapping Of Golf Course Green Sand Layers, Barry J. Allred, Robert S. Freeland, Katherine R. Grote, Edward L. Mccoy, Luis R. Martinez, Debra L. Gamble Dec 2016

Ground-Penetrating Radar Water Content Mapping Of Golf Course Green Sand Layers, Barry J. Allred, Robert S. Freeland, Katherine R. Grote, Edward L. Mccoy, Luis R. Martinez, Debra L. Gamble

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Information on the spatial distribution of water content across the sand layer component of a golf course green can be important to golf course superintendents for evaluating drainage effectiveness and scheduling irrigation. To estimate the bulk volumetric water content of the sand layer at point locations across the green, a technique was developed that combined (1) depth (or thickness) of the sand layer measured with a steel shaft tile probe, (2) radar signal two-way travel time from the base of the sand layer obtained using a ground-penetrating radar (GPR) system with 900 MHz antennas, and (3) an empirical equation relating …


Passive Rifting Of Thick Lithosphere In The Southern East African Rift: Evidence From Mantle Transition Zone Discontinuity Topography, Cory A. Reed, Kelly H. Liu, Patrick R. N. Chindandali, Belarmino Massingue, Hassan Mdala, Daniel Mutamina, Youqiang Yu, Stephen S. Gao Nov 2016

Passive Rifting Of Thick Lithosphere In The Southern East African Rift: Evidence From Mantle Transition Zone Discontinuity Topography, Cory A. Reed, Kelly H. Liu, Patrick R. N. Chindandali, Belarmino Massingue, Hassan Mdala, Daniel Mutamina, Youqiang Yu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To investigate the mechanisms for the initiation and early-stage evolution of the nonvolcanic southernmost segments of the East African Rift System (EARS), we installed and operated 35 broadband seismic stations across the Malawi and Luangwa rift zones over a 2 year period from mid-2012 to mid-2014. Stacking of over 1900 high-quality receiver functions provides the first regional-scale image of the 410 and 660 km seismic discontinuities bounding the mantle transition zone (MTZ) within the vicinity of the rift zones. When a 1-D standard Earth model is used for time-depth conversion, a normal MTZ thickness of 250 km is found beneath …


Mantle Structure Beneath The Incipient Okavango Rift Zone In Southern Africa, Youqiang Yu, Kelly H. Liu, Zhouchuan Huang, Dapeng Zhao, Cory A. Reed, Moikwathai Moidaki, Jianshe Lei, Stephen S. Gao Nov 2016

Mantle Structure Beneath The Incipient Okavango Rift Zone In Southern Africa, Youqiang Yu, Kelly H. Liu, Zhouchuan Huang, Dapeng Zhao, Cory A. Reed, Moikwathai Moidaki, Jianshe Lei, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Numerous investigations of the mature segments of the East African rift system (EARS) have significantly improved our understanding of the structure and processes associated with well-developed continental rifts. In contrast, knowledge of rifting processes at their early stage is still significantly limited. Here we present results from a teleseismic P-wave tomography investigation of the incipient Okavango rift zone (ORZ), which is located at the southwestern terminus of the EARS. P-wave relative travel-time residuals recorded by 17 recently deployed portable seismic stations were manually picked and inverted for three-dimensional upper-mantle and mantle transition-zone tomographic images beneath the ORZ and its adjacent …


A Dual-Porosity-Stokes Model And Finite Element Method For Coupling Dual-Porosity Flow And Free Flow, Jiangyong Hou, Meilan Qiu, Xiaoming He, Chaohua Guo, Mingzhen Wei, Baojun Bai Oct 2016

A Dual-Porosity-Stokes Model And Finite Element Method For Coupling Dual-Porosity Flow And Free Flow, Jiangyong Hou, Meilan Qiu, Xiaoming He, Chaohua Guo, Mingzhen Wei, Baojun Bai

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we propose and numerically solve a new model considering confined flow in dual-porosity media coupled with free flow in embedded macrofractures and conduits. Such situation arises, for example, for fluid flows in hydraulic fractured tight/shale oil/gas reservoirs. The flow in dual-porosity media, which consists of both matrix and microfractures, is described by a dual-porosity model. And the flow in the macrofractures and conduits is governed by the Stokes equation. Then the two models are coupled through four physically valid interface conditions on the interface between dual-porosity media and macrofractures/conduits, which play a key role in a physically …


Shear Wave Splitting Analyses In Tian Shan: Geodynamic Implications Of Complex Seismic Anisotropy, Solomon G. Cherie, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Fansheng Kong, Cory A. Reed, Bin B. Yang Jun 2016

Shear Wave Splitting Analyses In Tian Shan: Geodynamic Implications Of Complex Seismic Anisotropy, Solomon G. Cherie, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Fansheng Kong, Cory A. Reed, Bin B. Yang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Tian Shan is a tectonically complex intracontinental orogenic belt situated between the Tarim Basin and the Kazakh Shield. The vast majority of the previous shear wave splitting (SWS) measurements were presented as station averages, which are only valid when the anisotropy structure can be approximated by a single layer of anisotropy with a horizontal axis of symmetry, i.e., a model of simple anisotropy. A variety of anisotropy-forming hypotheses have been proposed based on the station-averaged measurements. In this study, we measure the splitting parameters at 25 stations that recorded high-quality data from a wide back azimuthal range for the …


The Mantle Transition Zone Beneath The Afar Depression And Adjacent Regions: Implications For Mantle Plumes And Hydration, Cory A. Reed, Stephen S. Gao, Kelly H. Liu, Y. Yu Mar 2016

The Mantle Transition Zone Beneath The Afar Depression And Adjacent Regions: Implications For Mantle Plumes And Hydration, Cory A. Reed, Stephen S. Gao, Kelly H. Liu, Y. Yu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Afar Depression and its adjacent areas are underlain by an upper mantle marked by some of the world's largest negative velocity anomalies, which are frequently attributed to the thermal influences of a lower-mantle plume. In spite of numerous studies, however, the existence of a plume beneath the area remains enigmatic, partially due to inadequate quantities of broad-band seismic data and the limited vertical resolution at the mantle transition zone (MTZ) depth of the techniques employed by previous investigations. In this study, we use an unprecedented quantity (over 14 500) of P-to-S receiver functions (RFs) recorded by 139 stations from …


A Uniform Database Of Teleseismic Shear-Wave Splitting Measurements For The Western And Central United States: December 2014 Update, Bin B. Yang, Kelly H. Liu, Haider H. Dahm, Stephen S. Gao Mar 2016

A Uniform Database Of Teleseismic Shear-Wave Splitting Measurements For The Western And Central United States: December 2014 Update, Bin B. Yang, Kelly H. Liu, Haider H. Dahm, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present a new version of a shear-wave splitting (SWS) database for the western and central United States (WCUS) using broadband seismic data recorded up to the end of 2014 to update a previous version that used data recorded prior to the end of 2012, when the USArray Transportable Array stations were still recording in the easternmost region of theWCUS. A total of 7452 pairs of additional measurements recorded by 1202 digital broadband seismic stations are obtained, and all the measurements in the previous database are rechecked. The resulting uniform SWS database contains a total of 23,448 pairs of well-defined …


The Role Of Pre-Existing Basement Fabrics In The Initiation Of Continental Rifting: The Okavango Rift Zone, Botswana, Angelica Alvarez Naranjo Jan 2016

The Role Of Pre-Existing Basement Fabrics In The Initiation Of Continental Rifting: The Okavango Rift Zone, Botswana, Angelica Alvarez Naranjo

Doctoral Dissertations

"Integrated geophysical, remote sensing, and field investigations of the Okavango Rift Zone (ORZ), Botswana indicate that a feedback between optimum-oriented basement structures and fluid flow influence the nucleation and growth of continental rifts in their incipient stages. The ORZ, the youngest rift of the East African Rift System, occurs within a Proterozoic inter-cratonic suture zone - the NE-trending Precambrian Damara/Ghanzi-Chobe orogenic belts. The Pleistocene to Holocene ORZ forms a ~450 km long and ~100 km wide half-graben bounded by NE-trending normal faults. Basement units within the Damara/Ghanzi-Chobe orogenic belts exhibit a well-developed NE-trending linear fabric (045-065) defined by parallel limbs …


Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck Jan 2016

Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck

Masters Theses

"The spatial distribution of fracture sets associated with buckle folds has been well documented in field studies. There are difficulties, however, in placing accurate constraints on the timing of the initiation of individual fracture sets during the deformation history of the fold under in-situ conditions. This study investigates specific conditions that give rise to the initiation of various fracture sets in the hinge and limb of a pericline, based on an analysis of the effective stress evolution during the processes of buckling and erosional unloading. A 3D finite element modeling approach is used to simulate the effective stress evolution in …


Fluid Flow Through Deformation Band, Huining Zhang Jan 2016

Fluid Flow Through Deformation Band, Huining Zhang

Masters Theses

"Cataclastic deformation bands, which are common in porous sandstone, have the potential to restrict fluid flow. Geological studies have shown that permeability of deformation band shear zones can be one to five orders of magnitude less than for the sandstone host rock. However, recent studies based on simplified analytical estimates have shown that fluid flow in jointed deformation bands may not be retarded since joints play an important role in conducting fluids. In this study, 2 dimensional finite element analysis (FEA) is used to simulate the total discharge flow rate through jointed deformations. Variations of single planar and conjugate jointed …


Periclinal Folding In Ozark Plateau: A Record Of Local Karst Collapse Or Regional Tectonic Forces?, Chao Liu Jan 2016

Periclinal Folding In Ozark Plateau: A Record Of Local Karst Collapse Or Regional Tectonic Forces?, Chao Liu

Masters Theses

"The Ordovician Rubidoux Formation of the Ozark Plateau, Missouri is typically identified as mechanically competent sub-horizontal beds of medium grained sandstone. North of Licking, MO, the Rubidoux Formation was deformed into a series of dome-and-basin shaped buckle folds, exposed in road cuts over a distance of ~10 km. Such folds are highly unusual within the Ozark Plateau and their origin remains controversial. Three major hypotheses have been proposed based on field observations and stereographic analysis. Given the pervasive distribution of karst collapse throughout Missouri, one hypothesis to explain these folds is that the Roubidoux Formation sagged into collapsed caverns. A …


Phytoforensics Tools: The Degradation And Detection Of Chlorinated Solvents In Integrated Systems, Tommy J. Goodwin Jr. Jan 2016

Phytoforensics Tools: The Degradation And Detection Of Chlorinated Solvents In Integrated Systems, Tommy J. Goodwin Jr.

Masters Theses

"Due to decades of mismanaged pollutants entering groundwater, subsurface pollution of various compounds has become a widespread challenge. Chlorinated solvents are the most common groundwater contaminants that persist in aquifers, and remediation of these wide-spread plumes is difficult. Bioremediation, permeable reactive barriers, and phytoremediation are remedial technologies that have been developed and applied to chlorinated solvents in groundwater systems. This study integrates these technologies in different combinations to demonstrate the remediation potential of this approach. Zerovalent iron (ZVI) and bioaugmentation with a Dehalococcoides sp. (DHC) culture were applied separately and in combination for degradation of perchloroethene (PCE). Salix pentandra were …


3d Seismic Structural And Stratigraphic Interpretation Of The Tui-3d Field, Taranaki Basin, New Zealand, Gorkem Yagci Jan 2016

3d Seismic Structural And Stratigraphic Interpretation Of The Tui-3d Field, Taranaki Basin, New Zealand, Gorkem Yagci

Masters Theses

"Identifying seismic structures and stratigraphy are important for exploration of hydrocarbons. The purpose of this study is to discover seismic structural and stratigraphic features and to utilize the results for interpreting depositional environments. A 3D seismic dataset from the Tui-3D Field, the Taranaki Basin, New Zealand with well data were used to visualize structures, to detect stratigraphic features, to identify main lithology, to understand depositional environment, and to describe seismic facies and reflection patterns of the target horizons. The major formations are in the Kapuni Group.

Seismic structural interpretation indicates thirty-two minor faults, which may play an important role in …


Structural Analysis And Fluid Flow Modeling Of The Kapuni Field, New Zealand, Jarret Taylor Baldwin Jan 2016

Structural Analysis And Fluid Flow Modeling Of The Kapuni Field, New Zealand, Jarret Taylor Baldwin

Masters Theses

"The Taranaki Basin is the largest hydrocarbon producing basin in New Zealand. A total area of over 330,000 km


Provenance And Depositional Environments Of Fluvial-Lacustrine Sandstones Of Lower Permian Lucaogou Low-Order Cycle, Bogda Mountains, Nw China, Xiaowei Peng Jan 2016

Provenance And Depositional Environments Of Fluvial-Lacustrine Sandstones Of Lower Permian Lucaogou Low-Order Cycle, Bogda Mountains, Nw China, Xiaowei Peng

Masters Theses

"Compositional and textural maturity of sandstones may reflect provenance lithology and sediment transport distance, which are useful for paleogeographic reconstruction. 37 sandstones in six outcrop stratigraphic sections in Tarlong-Taodonggou and Zhaobishan areas in the greater Turpan-Junggar rift basin were studied to investigate the fluvial-lacustrine sandstone provenance in lower Permian Lucaogou (LCG) low-order cycle, Bogda Mountains, NW China. 400 points were counted in each thin section. All the samples are classified into lithic arenites, subarenites, wackes, and mudrocks. Three Petrofacies are defined. Petrofacies A is characterized by a high lithic content which is dominantly basaltic lithics with minor sedimentary lithics and …


Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander Jan 2016

Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander

Doctoral Dissertations

"Five small lakes in southeast Missouri (Frisco, Pine Forest, and Bray Area lakes [Phelps County], and Cypress and Blue ponds [Bollinger County]) were cored for paleolimnological studies. Cores were evaluated for their sedimentology, palynology, and geochemistry. In two of these lakes (Bray Area and Pine Forest lakes) the planktonic algae were also studied in the water column, along with ecological parameters. Algae in the sediments were compared to algae in the water to understand the resistance of different species to decay, and a suggested methodology for this work is described. Reconstructions of the past environments around each lake were created …


Numerical Analysis Of Flexural Slip During Viscoelastic Buckle Folding, Davi Rodrigues Damasceno Jan 2016

Numerical Analysis Of Flexural Slip During Viscoelastic Buckle Folding, Davi Rodrigues Damasceno

Masters Theses

"Flexural slip is considered to be an important folding mechanism contributing in the development of different folds such as chevron, and kink-band buckle folds. Various filed studies have provided a general conceptual and qualitative understanding of flexural slip. However, quantitative evidence of the importance of the flexural slip mechanism during fold evolution is sparse, as the actual amount of surface parallel displacement, and timing, is difficult to measure accurately, due to the lack of suitable strain markers.

In this study 2D finite element analysis is used to overcome these disadvantages and to simulate flexural slip during viscoelastic buckle folding. Variations …


Paleogeogra Detrital Zircon Geochronology Of Upper Cambrian To Lower Mississippian Siliciclastic Strata Of The Ozark Dome And Vicinity, Bing Li Jan 2016

Paleogeogra Detrital Zircon Geochronology Of Upper Cambrian To Lower Mississippian Siliciclastic Strata Of The Ozark Dome And Vicinity, Bing Li

Masters Theses

"Siliciclastic strata exposed in the Ozark Dome provide Late Cambrian to Late Cretaceous snapshots of an evolving paleogeology and regional to far-field tectonic events. U-Pb ages of detrital zircons from the arkosic base of the Upper Cambrian Lamotte Formation reflect first cycle derivation from the adjacent ca. 1.31-1.48 Ga Granite-Rhyolite province, with subsidiary input from ca. 1.6-1.7 Ga Mazatzal basement. Feldspathic arenites near the top of the Lamotte Sandstone also contain significant quantities of detrital zircon grains of these ages, with additional peaks centered at ca. 2.7 and ca. 1.1 Ga, signaling the onset of extra-regional detrital input most likely …


Nonlinear Model And Qualitative Analysis For Coupled Axial/Torsional Vibrations Of Drill String, Fushen Ren, Baojin Wang, Suli Chen, Zhigang Yao, Baojun Bai Jan 2016

Nonlinear Model And Qualitative Analysis For Coupled Axial/Torsional Vibrations Of Drill String, Fushen Ren, Baojin Wang, Suli Chen, Zhigang Yao, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A nonlinear dynamics model and qualitative analysis are presented to study the key effective factors for coupled axial/torsional vibrations of a drill string, which is described as a simplified, equivalent, flexible shell under axial rotation. Here, after dimensionless processing, the mathematical models are obtained accounting for the coupling of axial and torsional vibrations using the nonlinear dynamics qualitative method, in which excitation loads and boundary conditions of the drill string are simplified to a rotating, flexible shell. The analysis of dynamics responses is performed by means of the Runge-Kutta-Fehlberg method, in which the rules that govern the changing of the …


Experimental Investigation Of Fracture Width Limitations Of Granular Lost Circulation Treatments, Mortadha Al-Saba, Runar Nygaard, Arild Saasen, Olav Magnar Nes Jan 2016

Experimental Investigation Of Fracture Width Limitations Of Granular Lost Circulation Treatments, Mortadha Al-Saba, Runar Nygaard, Arild Saasen, Olav Magnar Nes

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Drilling fluid losses into fractured shales is a major challenge. Lost circulation treatments are widely applied to mitigate the losses; however, the effectiveness of these treatments is affected by different physical properties of the used lost circulation materials (LCM). This paper presents an experimental investigation to study the effect of LCM type, concentration, particle size distribution, temperature, and LCM shape on the formed seal integrity, with respect to differential pressure, at different fracture widths. The overall objective of this study is to address the effectiveness of LCM treatments in sealing fractured shales, with specific application to the over consolidated Barents …


Gravity And Magnetic Investigations Of The North-Eastern Kansas Section Of The Midcontinent Rift System, Ozgun Kamil Sahin Jan 2016

Gravity And Magnetic Investigations Of The North-Eastern Kansas Section Of The Midcontinent Rift System, Ozgun Kamil Sahin

Masters Theses

"The Midcontinent Rift System (MRS) is a major Precambrian magmatic province on the North American continent. It formed when the North American craton began to split apart during the Mesoproterozoic era (1,100 Ma). As a result of the extension and possibly the effects of a rising mantle plume, a thick layer of basalt and numerous reverse and normal faults were formed. The basalt layer is buried below sedimentary formations and makes it difficult for seismic techniques to image. On the other hand, gravity and magnetic methods can be utilized for focused depths, and the basalt layer of the system can …


Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori Jan 2016

Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori

Masters Theses

"Through the analysis of both U-Pb and (U-Th)/He ages from detrital zircon grains we can constrain thermal histories by establishing ages which correspond to crystallization and exhumation events, respectively. This combined geo-/thermochronologic approach is used here to constrain the history of the polyphase Nacimiento fault. This fault traverses central and southern California and has accumulated at least 150 km of slip since Late Cretaceous time. Major displacements along the structure occurred between 75 and 56 Ma, with Neogene to Holocene strike-slip remobilization linked to the San Andreas fault system. Detrital zircon U-Pb geochronology from Franciscan subduction assemblages west of the …


2d Seismic Data And Gas Chimney Interpretation In The South Taranaki Graben, New Zealand, Taqi Talib Alzaki Jan 2016

2d Seismic Data And Gas Chimney Interpretation In The South Taranaki Graben, New Zealand, Taqi Talib Alzaki

Masters Theses

"The Taranaki Basin is one of the major oil and gas producing basins offshore New Zealand. The study area covers an area of 10,000 km2 in the basin, and includes 171 2D seismic lines and six wells, which are provided by the New Zealand Petroleum & Minerals. Some previous studies refer to the study area as the South Taranaki Graben.

This thesis provides detailed mapping and interpreted subsurface stratigraphy and structure of five horizons, i.e. basement top, Pakawau Group top, Kapuni Group top, Wai-iti Group top, and seafloor. It undertakes studies of the relation between the basin evolution, faults, …


Seismic Anisotropy And Mantle Dynamics Beneath The Central And Western United States, Bin Yang Jan 2016

Seismic Anisotropy And Mantle Dynamics Beneath The Central And Western United States, Bin Yang

Doctoral Dissertations

"Various tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other seismic stations in the central and western United States (CWUS) provide a distinct opportunity to test different anisotropy-forming mechanisms. For the first part of the study, a total of 4138 pairs of well-defined shear wave splitting (SWS) parameters observed at 445 stations on the northern Great Plains show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating …


Origin Of Lacustrine Carbonate-Dominated Clinoforms In The Lower-Permian Lucaogou Low-Order Cycle, Southern Bogda Mountains, Nw China, Yiran Lu Jan 2016

Origin Of Lacustrine Carbonate-Dominated Clinoforms In The Lower-Permian Lucaogou Low-Order Cycle, Southern Bogda Mountains, Nw China, Yiran Lu

Masters Theses

"Lacustrine carbonate clinoforms deposit can reflect ancient lake condition like paleoclimate and lake type. Complex lithofacies of a carbonate-dominated clinoform package in lower Permian Lucaogou low order cycle, Bogda Mountains, NW China, provide clues on clinoform-forming processes in a half-graben lake. The clinoform package is ~5.2 m thick, prograding from S to N for ~200 m with a maximum 15o dip angle, and spans ~4 km laterally. A clinoform consists of a lower siliciclastic-rich and an upper carbonate-rich beds, forming a clinoform cycle. Results of petrographic study of 30 thin sections suggest that the clinoform package is composed of mixed …


Imaging Reinforced Concrete: A Comparative Study Of Ground Penetration Radar And Rebarscope, Abhishek Kodi Jan 2016

Imaging Reinforced Concrete: A Comparative Study Of Ground Penetration Radar And Rebarscope, Abhishek Kodi

Masters Theses

"Geophysical techniques have been playing a very vital role in subsurface imaging in the recent past. Technology has been making it both reliable and convenient to utilize non-destructive geophysics techniques like Ground Penetration Radar, Induction current based Rebarscope, Seismic methods, ERT, etc. The applications range from shallow subsurface investigation of Bridge decks to old tunnels, mapping of rabars in a pre-existing construction and analyzing the concrete strength.

The thesis constitutes of a comparative study and analysis of a Ground Penetration Radar system and a Rebarscope. Individual parameters obtained directly from the study and obtained indirectly from the study shall be …


Variable Stress Orientations In The Offshore Nile Delta: The Role Of Salt As A Mechanical Detachment Horizon, Weicheng Zhang Jan 2016

Variable Stress Orientations In The Offshore Nile Delta: The Role Of Salt As A Mechanical Detachment Horizon, Weicheng Zhang

Masters Theses

"The offshore Nile Delta is characterized by variations of the maximum horizontal stress orientation in subsalt and supra-salt sequences. Margin-parallel SH, typical for tertiary deltas, is observed for regions that are below or do not contain evaporites. In sequences underlain by evaporates pre-dominantly margin-normal SH is observed. This observation yielded the first conclusive in situ evidence that salt acts as a mechanical detachment layer. In this study, 3D finite element analysis (FEA) is used to simulate the total stress distribution in the offshore Nile Delta featuring evaporate sequences. Several parameters such as different salt sequence geometries, friction coefficient on faults, …


Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman Jan 2016

Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman

Masters Theses

"This article presents the crystallization age of, and composition of olivine phenocrysts within an alnoite of, the Avon Alkaline Igneous Province (AAIP) of Ste. Genevieve County, Missouri. The AAIP is an ultramafic igneous province consisting of approx. 80 known intrusives of diverse lithology and texture. 40Ar/39 Ar geochronology indicates an emplacement age of 386 +/- 1 Ma, which establishes the AAIP as the only known Devonian-age ultramafic igneous body in the Midwestern U.S. Study of the AAIP provides a unique opportunity to characterize the Devonian-age subcontinental mantle and the processes that generated the suite of ultramafic rocks present …