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Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif

Browse all Theses and Dissertations

A stromatolite is a laminated benthic microbial deposit. Its uniqueness arises from being present since the Precambrian to the present. Stromatolites recorded a peak time during the Mesoproterozoic, subsequently they witnessed abrupt rises and falls in abundance with the steepest decline in the Ordovician period, from which it never recovered from. There is no consensus yet regarding the reasons behind the decline of stromatolites. Thus the decline of these microbial deposits remains an enigma. Additionally, a literature gap exists regarding the reasons that specifically led to the Ordovician decline. Accordingly, the focus of this literature-based MSc. thesis is to find …

A Structural Analysis Of The El Kasr Structure In The Western Desert Of Egypt, Trevor Charles Ellis

Masters Theses

"The El Kasr structure was studied in order to investigate the origins and evolution of the enigmatic Desert Eyes structures of the Western Desert due to its accessibility and uniqueness among the structures. The El Kasr structure, an elongate structural basin with low limb dips, is unique among the "Desert Eyes" structures in that it: 1) occurs in isolation in otherwise horizontal sedimentary rock, 2) the long dimension of the basin is oriented NNW, 3) it is closely spatially associated with the less common NNW fault zones, and 4) is composite in nature. The structure was investigated using remote sensing …

Application Of Various Remote Sensing And Aerial Photography Data Sets To Resolve Surface Structure In Areas Of Poor Exposure: Examples From Kamchatka Peninsula, Russia And Katalla Area, Alaska Usa, Sarah Natalie Heinlein

Open Access Theses & Dissertations

For many years now remote sensing data sets and application techniques of these various data have been routinely used in geological studies. Some of these studies are as basic as using Google Earth applications for general reconnaissance to more sophisticated methods for energy exploration or development of active tectonic models for a region. This dissertation presents data from two study areas within the northern pacific region utilizing a number of remote sensing and aerial photography data: 1) Kamchatka Peninsula, Russia, and 2) Katalla area of southern Alaska, USA. The Kamchatka Peninsula, Russia study evaluates surface geomorphology which includes the morphology …

Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan

Theses and Dissertations

Many of the earth’s rocks exhibit anisotropic characteristics. Anisotropy is particularly common in many sedimentary rocks, such as shales. Anisotropy is defined as the spatial alignment of mineral grains, layers, fractures and stresses which causes elastic wave velocity and other elastic properties to vary with direction. There are two types of anisotropy: intrinsic and stress-induced. Intrinsic anisotropy is caused by beddings, microstructures or aligned fractures formed during deposition. Stress-induced anisotropy is caused by strain associated with external stresses. Intrinsic anisotropy originates in the absence of external stresses, while stress-induced anisotropy results from tectonic and overburden stresses. The style of earth …

Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak

Graduate Theses and Dissertations

The surface liquids and lake regions of Titan are studied utilizing three unique techniques, the results of which are reported in this dissertation. The development of a facility to simulate the surface conditions of Titan, and to conduct experiments on samples within that facility, brings an understanding of Titan's surface not possible through observation and modeling alone. The properties of this facility are presented, including conceptual methodology, design, implementation, performance, and experimental results. The facility, the main component of which is a simulation chamber, allows for Titan temperatures of 90 - 94 K and a 1.5 bar N2 atmosphere. The …

Discriminant Analysis Of Xrf Data From Sandstones Of Like Facies And Appearance: A Method For Identifying A Regional Unconformity, Paleotopography,And Diagenetic Histories, Stephen Paul Phillips

Theses and Dissertations

The placement of an unconformable surface within a stratal succession affects the interpreted thickness of units and sequences in contact with that surface. Unit thickness influences the interpretation of basin subsidence, paleotopography, diagenesis, and depositional style. Accurate placement of an unconformity results in true formational thicknesses for formations associated with that unconformity. True thicknesses aid in producing more precise surface to subsurface correlations, isopach maps, and paleogeographic maps. An unconformity may be difficult to identify in the stratal succession due to similar rocks above and below the unconformity and the presence of multiple candidate surfaces. Using statistical discriminant analysis of …

Holocene Earthquakes And Late Pleistocene Slip-Rate Estimates On The Wassuk Range Fault Zone, Nevada, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky

Earth and Environmental Geosciences Faculty Research

The Wassuk Range fault zone is an 80‐km‐long, east‐dipping, high‐angle normal fault that flanks the eastern margin of the Wassuk Range in central Nevada. Observations from two alluvial fan systems truncated by the fault yield information on the vertical slip rate and Holocene earthquake history along the range front. At the apex of the Rose Creek alluvial fan, radiocarbon dating of offset stratigraphy exposed in two fault trenches shows that multiple earthquakes resulted in 7.0 m of vertical offset along the fault since ∼9400 cal B.P. These data yield a Holocene vertical slip rate of 0.7±0.1  mm/yr. The south trench …

Rock Properties And Structure Within The San Andreas Fault Observatory At Depth (Safod) Borehold, Northwest Of Parkfield, California: In Situ Observations Of Rock Deformation Processes And Fluid-Rock Interactions Of The San Andreas Fault Zone At ~ 3 Km Depth, Kelly Keighley Bradbury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The San Andreas Fault Observatory at Depth (SAFOD) is a scientific drilling experiment situated along the central creeping segment of the San Andreas Fault, near Parkfield, California, and north of a segment of the fault that has experienced large historical earthquakes. Drilling into active fault zones allows scientist’s to examine in situ rock samples and to record real-time data.

The main goal of this study is to characterize the geologic setting and rock properties of the San Andreas fault at ~ 3 km depth in the SAFOD borehole. In this region, the fault deforms nearly continuously through aseismic creep and …

Geothermal Alteration Of Basaltic Core From The Snake River Plain, Idaho, Christopher Joseph Sant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Snake River Plain is located in the southern part of the state of Idaho. The eastern plain, which this study focuses on, is a trail of volcanics from the Yellowstone
hotspot. Three exploratory geothermal wells were drilled on the Snake River Plain. This project studies basaltic core from the first well at Kimama, north of Burley, Idaho. The objectives of this project are to establish zones of geothermal alteration and analyze the potential for geothermal power production near the center of the Snake River Plain. Thirty samples from 1,912 m of core were sampled and analyzed. Mineral data, temperature …

The Mesozoic Carbonate Deposits From The Borehole 6042 Deleni (Transylvanian Depression), Ioan I. Bucur, Marcel-Adrian Piteiu, Emanoil SăSăRan

Studia UBB Geologia

The borehole 6042 Deleni is among the few wells located in the central part of the Transylvanian Depression that crossed the rocks in the basement. Among these, the Mesozoic deposits were cross-cut along 916 m. Based on the investigations carried out on core samples from the Mesozoic deposits three carbonate units attributed to the Late Oxfordian -Tithonian (?Neocomian) have been separated. A preliminary evaluation of the terrigenous and carbonate-terrigenous deposits overlaying the carbonate ones indicated an Aptian-Albian, respectively Senonian age. Considerations on the paleoenvironment of the Mesozoic deposits studied are also presented.

The Miocene Calcareous Nannofossils From Bistriţa Area (Transylvania, Romania), Carmen Chira, Ana-Maria Vulc

Studia UBB Geologia

The Middle Miocene (Badenian, Sarmatian and Pannonian) deposits from the region of Bistriţa, between the localities: Susenii Bârgăului, Livezile, Bistriţa, Sărata, Sărăţel, Budacu de Sus (Transylvanian Basin) have been analysed from the nannofloral point of view. The nannofossils are relatively scarce, excepting the ones related to Lower Badenian deposits. Only the fossil index for NN5 Zone – Sphenolithus heteromorphus, and for NN6 Zone – Discoaster exilis have been identified.

A Study On The Geology Of The Ţaga Region (Cluj District), Ioan MâRza

Studia UBB Geologia

The geological formations from Ţaga area (Cluj District) are Sarmatian in age (in outcrops) and Badenian (under surface). Lithologically, they are represented mainly by sands and sometimes fine sediments (clays, marls), interbedded with volcanic tuffs a low fossil content. The Badenian is the host of gas accumulations, concentrated in dome structures.

Microbial Structures And Microencrusters In The Upper Jurassic - Lower Cretaceous Deposits From Buila-Vânturariţa Massif (South Carpathians), Andreea Ut̡A, Ioan I. Bucur

Studia UBB Geologia

The Upper Jurassic – Lower Cretaceous limestones from Buila-Vânturariţa massif partly consisting of reef build-ups, are characterised by an important component of microbial organisms. This paper describes and illustrates some of the most important structures interpreted as having a microbial nature: “Tubiphytes” and Bacinella-type structures, cyanobacterial structures, micritic crusts, and peloidal structures. Most of these structures are related to different shallow-water environments, from intertidal, high-energy environment, to protected low energy subtidal environment.

Arenite Concretions With Axial Channel From The Badenian Deposits Of Cheia (Turda) - A New Type Of Concretions, Ioan Mârza, Ciprian Constantina, Horea PâRlea

Studia UBB Geologia

The paper introduces a new type of arenite concretions (max. 40-50 cm in diameter). Spheroidal concretions with an axial cylindrical channel (1-6 cm in diameter) resulted from the levigation of the concretion centre consisting of soft fusiform clasts with a clayey-carbonate composition. The concretions are hosted by a level of Badenian sandstones and microconglomerates (about 10-m thick) which occur in the place called “Groapa cu Piersici” (Cheia, Turda).

The Spatial Extension And The Age Of The Tomnatec Formation In Audia Nappe, Liviu Ionesi, Florin Florea

Studia UBB Geologia

No abstract provided.

Major Elements Geochemistry Of The Breiner Baiut Ore Deposit (Gutai Mountains, Eastern Carpathians), Dan Costin

Studia UBB Geologia

The Breiner Băiuţ epithermal vein – type deposit is basically a base metal ore body with important amounts of gold and silver. The frequency distribution pattern of the major elements (Au, Ag, Pb, Zn, Cu, S) is complex in many cases, but at some mining levels it is lognormal. The correlation coefficient "r" has been calculated for six pairs of major elements. The values are positive and indicate strong correlations between these elements. The average grades values for each major element at all levels have been used to highlight the vertical variation of chemistry of the mineralization. The ore body …

Evolution Of The Earliest Horses Driven By Climate Change In The Paleocene-Eocene Thermal Maximum, Ross Secord, Jonathan I. Bloch, Stephen G. B. Chester, Doug M. Boyer, Aaron R. Wood, Scott L. Wing, Mary J. Kraus, Francesca A. Mcinerney, John Krigbaum

Department of Earth and Atmospheric Sciences: Faculty Publications

Body size plays a critical role in mammalian ecology and physiology. Previous research has shown that many mammals became smaller during the Paleocene-Eocene Thermal Maximum (PETM), but the timing and magnitude of that change relative to climate change have been unclear. A high-resolution record of continental climate and equid body size change shows a directional size decrease of ~30% over the first ~130,000 years of the PETM, followed by a ~76% increase in the recovery phase of the PETM. These size changes are negatively correlated with temperature inferred from oxygen isotopes in mammal teeth and were probably driven by shifts …

Sedimentary Succesion Of The Lower Cretaceous Deposits From The North-Western Part Of Pădurea Craiului (Apuseni Mountains, Romania), Daniel F. Lazar, Ioan I. Bucur, Ioan Cociuba, Emanoil Sasaran

Studia UBB Geologia

Within the general succession of the Lower Cretaceous deposits from the Vârciorog-Dobreşti area (Pădurea Craiului Mountains), carbonate and terrigenous deposits were identified. The limestones were assigned to two distinctive lithostratigraphic units: the Valea Măgurii and Vârciorog formations. Based on the orbitolinids Palorbitolina lenticularis and Mesorbitolina texana their ages are assigned to the early Aptian, and respectively late Aptian–Albian. The terrigenous facies mainly include fine grained deposits (clays, siltites, marls) and, to a lesser extent, coarser ones (glauconitic sandstones and conglomerates), and they are attributed to the Ecleja and Vârciorog formations. The marls of the Ecleja Formation have been observed in …

Vent-Fault Spatial Study Of Selected Volcanic Fields Of Southwestern North America And Mexico, Michelle Leonard

USF Tampa Graduate Theses and Dissertations

Of fundamental concern in volcanic hazard and risk assessment studies of volcanic systems is what role crustal structures might play in the ascent of magma through the crust. What are the processes that govern the spatial distribution and timing of eruptions, especially in populated areas or near sensitive facilities? Many studies have drawn the conclusion that faults play a critical role as easily–exploitable crustal weaknesses along which magma can ascend. Great care must be used when assuming a causative relationship between patterns of vents and faults especially when such relationships may be incorporated into hazard assessment models or other forecasting …

Extent And Mechanism Of Footwall Shear Adjacent To The Ruby's Inn Thrust Fault, Southern Utah, Skyler B. May, Roger E. Leavitt, John S. Maclean

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Ruby’s Inn Thrust, located in the Bryce Canyon region, is an uncharacteristic demonstration of a south-directed shortening episode located near the predominately east-directed contractional structures of the Sevier Orogeny. The Paleocene to Eocene Claron Formation in the footwall of the Ruby’s Inn Thrust contains conjugate shear structures and vertical fault planes with slickensides and slickenlines, indicating complex multidirectional shearing. We determined the north-south extent of a broad shear zone along a traverse immediately west of Bryce Canyon National Park, and shearing intensifies slowly from the main thrust at the northern end of our traverse to a maximum intensity at …

Strain Analysis On The Sub-Lay Dam Unconformity Near Jumbo, Alabama, Clinton Barineau

Faculty Bibliography

No abstract provided.

Hydrostratigraphic Interpretation Of Test-Hole And Surface Geophysical Data, Elkhorn And Loup River Basins, Nebraska, 2008 To 2011, Christopher M. Hobza, Paul A. Bedrosian, Benjamin R. Bloss

United States Geological Survey: Water Reports and Publications

The Elkhorn-Loup Model (ELM) was begun in 2006 to understand the effect of various groundwater-management scenarios on surface-water resources. During phase one of the ELM study, a lack of subsurface geological information was identified as a data gap. Test holes drilled to the base of the aquifer in the ELM study area are spaced as much as 25 miles apart, especially in areas of the western Sand Hills. Given the variable character of the hydrostratigraphic units that compose the High Plains aquifer system, substantial variation in aquifer thickness and characteristics can exist between test holes. To improve the hydrogeologic understanding …

Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong

Open Access Theses & Dissertations

I use updated gravity data, available aeromagnetic data, and other geophysical information as constraints to develop 2D and 3D structural models of density and magnetic susceptibility to better locate and determine the shape of the Border Ranges fault system (BRFS), the Border Range ultramafic and mafic assemblages and other forearc-arc boundary structures in south-central Alaska, that have previously been studied in only limited detail. There are three geophysical research projects that form the chapters of the dissertation. First, I estimated near-surface density variations in the central Kenai Peninsula based on the adaptation of the Nettleton (1939)-Parasnis (1952) method using Tarantola …

Mines And Minerals Of The Western Kentucky Fluorspar District, Warren H. Anderson, Thomas N. Sparks

Map and Chart--KGS

This map shows all the known and identified mines, mineral prospects, and igneous intrusions (dikes or sills) in the Western Kentucky Fluorspar District, compiled from thousands of maps and files, creating an up-to-date, comprehensive catalog for the district. The district has been extensively mined for more than 120 years and was once the largest producer of fluorspar (fluorite) in the United States.

Millions of tons of vein ore minerals (fluorite, zinc, lead, and barite) has been produced from these mines, and substantial reserves still remain. New mining and exploration activity has renewed interest in the district, and the industry will …

Varying Sediment Sources (Hudson Strait, Cumberland Sound, Baffin Bay) To The Nw Labrador Sea Slope Between And During Heinrich Events 0 To 4, J. T. Andrews, Donald C. Barber, A. E. Jennings, D. D. Erbel, B. Maclean, M. E. Kirby, J. S. Stoner

Geology Faculty Research and Scholarship

Core HU97048-007PC was recovered from the continental Labrador Sea slope at a water depth of 945m, 250km seaward from the mouth of Cumberland Sound, and 400km north of Hudson Strait. Cumberland Sound is a structural trough partly floored by Cretaceous mudstones and Paleozoic carbonates. The record extends from ~ 10 to 58k cal a BP. On-board logging revealed a complex series of lithofacies, including buff-colored detrital carbonate-rich sediments [Heinrich (H)-events] frequently bracketed by black facies. We investigate the provenance of these facies using quantitative X-ray diffraction on drill-core samples from Paleozoic and Cretaceous bedrock from the SE Baffin Island Shelf, …

Active Tectonics And Earthquake Destructions In Caves Of Northern And Central Switzerland, Arnfried Becker, Philipp Häuselmann, Jost Eikenberg, Eric Gilli

International Journal of Speleology

The present publication focuses on the study of caves in northern and central Switzerland in order to detect and date historical earthquakes and active tectonic displacements by investigations of broken and resealed or displaced speleothems datable by U/Th and ¹⁴C. While it can be shown that these methods are potentially suitable, the ages obtained are often beyond the range of historically recorded earthquakes, and it cannot be proved that the observed and dated events are related to a seismic event. Particularly this is true for the caves in central Switzerland, where most ages in the Melchsee-Frutt region were beyond …

Holocene Earthquakes And Late Pleistocene Slip Rate Estimates On The Wassuk Range Fault Zone, Nevada, Usa, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky

Earth and Environmental Geosciences Faculty Research

The Wassuk Range fault zone is an 80‐km‐long, east‐dipping, high‐angle normal fault that flanks the eastern margin of the Wassuk Range in central Nevada. Observations from two alluvial fan systems truncated by the fault yield information on the vertical slip rate and Holocene earthquake history along the range front. At the apex of the Rose Creek alluvial fan, radiocarbon dating of offset stratigraphy exposed in two fault trenches shows that multiple earthquakes resulted in 7.0 m of vertical offset along the fault since ∼9400 cal B.P. These data yield a Holocene vertical slip rate of 0.7±0.1  mm/yr. The south trench …

Geology Of The Eau Claire Formation And Conasauga Group In Part Of Kentucky And Analysis Of Their Suitability As Caprocks For Deeper Co2 Sequestration, Ralph E. Bandy Iii

Theses and Dissertations--Earth and Environmental Sciences

Carbon sequestration, or carbon capture and storage (CCS), is the process of capturing anthropogenically generated CO₂, transporting the CO₂ to an injection site, and then injecting the CO₂ into suitable reservoirs for long-term storage, or sequestration. Integral to the successful sequestration of CO₂ is an understanding of the confining intervals (seals) above potential reservoirs. The purpose of this thesis research was to perform a detailed geological study of the Eau Claire Formation and equivalent parts of the Conasauga Group in part of the Ohio River Valley region in order to better evaluate its suitability as …

Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis

Theses and Dissertations

The Deccan Plateau in western and central India has been a major area of interest for researchers since the 1800s. In 1840, James Sowerby described the molluscan collection sent to him by John Malcolmson. In 1860, Stephen Hislop identified new molluscan species and redescribed based on better preserved material. Although this seminal work was comprehensive, interpretations have changed since the mid 1800s. Species need to be reassigned to current and/or accurate taxa, as well as revalidated statistically. Seventeen character traits were measured on over 600 specimens from five eastern Deccan Plateau localities representing a stratigraphic and temporal sequence. Cluster analysis …

A Remote Sensing Approach To Characterize The Hydrogeology Of Mountainous Areas: Application To The Quito Aquifer System (Qas), Ecuador, Miriam Rios-Sanchez

Dissertations, Master's Theses and Master's Reports - Open

Climate change, intensive use, and population growth are threatening the availability of water resources. New sources of water, better knowledge of existing ones, and improved water management strategies are of paramount importance. Ground water is often considered as primary water source due to its advantages in terms of quantity, spatial distribution, and natural quality. Remote sensing techniques afford scientists a unique opportunity to characterize landscapes in order to assess groundwater resources, particularly in tectonically influenced areas. Aquifers in volcanic basins are considered the most productive aquifers in Latin America. Although topography is considered the primary driving force for groundwater flows …