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Theses and Dissertations

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Full-Text Articles in Earth Sciences

Complexity In Overmarsh Circulation, Jessica Chassereau Sullivan Jan 2015

Complexity In Overmarsh Circulation, Jessica Chassereau Sullivan

Theses and Dissertations

Overmarsh circulation is highly complex with variations in current direction over very short timescales and flowpaths that differ substantially between flood and ebb cycles. Understanding such flow complexities in salt marshes is important because they inherently impact the distribution of sediment, larvae and nutrients throughout the marsh, and hence, the ecogeomorphic feedbacks that control landscape evolution. The purpose this Ph.D. research is to quantitatively evaluate the effects of salt marsh topography on overmarsh circulation in a Georgia salt marsh. This dissertation is comprised of three parts. First, digital elevation models (DEMs) were compared to characterize how well airborne lidar (light …


Proxy Development And Application For Reconstructing The Surface Ocean Carbonate System, Brittney J. Marshall Jan 2015

Proxy Development And Application For Reconstructing The Surface Ocean Carbonate System, Brittney J. Marshall

Theses and Dissertations

Over the last two centuries, human activities have led to an unprecedented rate of carbon input into the atmosphere and oceans resulting in an alarmingly rapid decline in surface ocean pH, a process referred to as ocean acidification (OA). This process is leading to an observed decline in the carbonate ion concentrations ([CO3 2-]) in seawater – an ion that a large number of marine organisms (e.g. corals, foraminifera) utilize to secrete their skeletons and shells. The ability to identify past ocean acidification events using the marine sedimentary record can shed light on future impacts of the modern OA dilemma. …


Interplay Of Porous Media And Fracture Stimulation In Sedimentary Enhanced Geothermal Systems : Red River Formation, Williston Basin, North Dakota, Caitlyn M. Hartig Jan 2015

Interplay Of Porous Media And Fracture Stimulation In Sedimentary Enhanced Geothermal Systems : Red River Formation, Williston Basin, North Dakota, Caitlyn M. Hartig

Theses and Dissertations

Fracture stimulated enhanced geothermal systems (EGS) can be installed in both crystalline rocks and sedimentary basins. The Red River Formation (Ordovician), which lies between 3.6 and 4.2 km depth in the Williston Basin, is a viable site for installation of sedimentary EGS (SEGS). SEGS is possible there because temperatures in the formation surpass 140° Celsius and the permeability is 0.1-38 mD; fracture stimulation can be utilized to improve performance. The main objectives of this project were 1) to determine the spatial variation of the intrinsic properties of the Red River Formation across the study area, and 2) to understand the …


Geothermal Regime Of The Williston Basin In North Dakota, Faye N. Ricker Jan 2015

Geothermal Regime Of The Williston Basin In North Dakota, Faye N. Ricker

Theses and Dissertations

Understanding the thermal regime of a large intracontinental basin such as the Williston Basin can be enhanced by analysis of the relationships among radiogenic heat production, surface heat flow, formation temperatures, and gravity and magnetic anomaly patterns. Digital processing of the spatial and causal relationships gives insight into the effect of basement heat production on the thermal state of the basement rocks and the overlying sedimentary successions. These relationships provide valuable insight on the radioactive heat contribution to heat flow, heat flow from the lower crust, composition of the upper crust, and the potential for geothermal power generation. The specific …


Reservoir Analysis Of The Birdbear Formation (Devonian) In Northwestern North Dakota, Mitchell V. Sigler Jan 2015

Reservoir Analysis Of The Birdbear Formation (Devonian) In Northwestern North Dakota, Mitchell V. Sigler

Theses and Dissertations

The Birdbear Formation of northwestern North Dakota is a carbonate-evaporite unit deposited on a rimmed carbonate platform during the Late Devonian. The upper and lower contacts are conformable and the formation has been previously divided into two informal upper and lower members. Analyses of core intervals, thin sections, total organic carbon, and wire line logs have allowed for the identification of three informal units that are divided based on lithologic changes, depositional settings, and reservoir characteristics of the formation. Each unit is identified and mapped across the study area using core to log correlations. The units are recognized and named …


The Geologic Implications Of The Factors That Affected Relative Sea-Level Positions In South Carolina During The Pleistocene And The Associated Preserved High-Stand Deposits, William Richardson Doar Iii Dec 2014

The Geologic Implications Of The Factors That Affected Relative Sea-Level Positions In South Carolina During The Pleistocene And The Associated Preserved High-Stand Deposits, William Richardson Doar Iii

Theses and Dissertations

This work utilizes the current understanding of South Carolina geology to provide a stratigraphic review of the late-Pliocene and Pleistocene marine deposits. Almost two centuries of recorded geological study includes geomorphic and stratigraphic units that were described, proposed, revised, abandoned, and revived. Along with the history of the age assignments, changes in geological time scales, and the changes in the understanding of geological concepts, this review is necessary because two concurrent and conflicting stratigraphies exist for late-Pliocene and Pleistocene marine sediments that record multiple sea-level transgressions that were more often destructive than constructive. The result, when tested against existing geological …


Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson Dec 2014

Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson

Theses and Dissertations

Climate change is having demonstrable, worldwide impacts on ecological systems in ways that have modified aspects of organism behavior. Plant phenologies have responded to warmer temperatures in a variety of ways that may have implications for long-term species survival. How germination phenology changes in response to warmer climate is a largely unexplored question yet the ability of a plant to advance or delay germination in unfavorable conditions is critical for survival. Knowing the relative success and timing of germination under different climate regimes is important in understanding whether species can keep pace with the rate of climate change via migration …


Temporal Constraints On Holocene Initiation And Termination Of Mound Development At An Episodic Gas Hydrate And Cold Seep System, Woolsey Mound, Northern Gulf Of Mexico, Nathan Robinson Dec 2014

Temporal Constraints On Holocene Initiation And Termination Of Mound Development At An Episodic Gas Hydrate And Cold Seep System, Woolsey Mound, Northern Gulf Of Mexico, Nathan Robinson

Theses and Dissertations

Woolsey Mound is a thermogenic gas hydrate and cold seep system in the deepwater (900m) Gulf of Mexico. A set of sub-bottom seismic profiles acquired at MC-118 Woolsey Mound provide decimeter-scale vertical resolution of the upper ~50m of the subsurface throughout the lease block. Integration of these data with radiocarbon, lithostratigraphic, and biostratigraphic data from shallow gravity cores provides the basis for detailed interpretation of the mound evolution within the last 12,000 years. Uniform sedimentation during the Last Glacial Maximum and following changes in sediment distribution over MC-118 suggests modern mound activity did not begin until at least ~12ka. Development …


Modeling Mussel Mortality: Investigating The Importance Of Swash And The Potential Implications Of Changing Wave Environments, Shadow Leigh Gulledge Dec 2014

Modeling Mussel Mortality: Investigating The Importance Of Swash And The Potential Implications Of Changing Wave Environments, Shadow Leigh Gulledge

Theses and Dissertations

Rising sea level and increases in temperature are causing biogeographic shifts in intertidal zones and can also lead to shifts in the local vertical zonation of organisms due to changes in body temperature during aerial exposure during low tide. Swash is an important determinant of aerial body temperatures, and vulnerability of intertidal zones to changes in climate could potentially depend on how much and how often animals are cooled by waves. While wave heights (and thus swash) are generally expected to increase with climate change, anthropogenic physical structures, such as breakwaters and wave energy converters, can decrease wave height and …


Remote Sensing Satellite Image Acquisition Planning: Framework, Methods And Application, Shufan Liu Dec 2014

Remote Sensing Satellite Image Acquisition Planning: Framework, Methods And Application, Shufan Liu

Theses and Dissertations

This dissertation explores the theories and methods of satellite remote sensing image acquisition planning within a spatial temporal context. For many time sensitive applications, such as disaster emergency response, timely acquisition of critical information is the key to intelligent and effective decision making. Remote sensing plays an important role in information collection for these time sensitive applications. Imagery collected from hundreds of remote sensing satellite sensors offer accurate, frequent and almost instantaneous data covering the Earth in a relatively short time. However, determining which satellite sensors can provide an appropriated kind of imageries during a restricted collection window for the …


Normal Fault Block Or Giant Landslide? Baldy Block, Wasatch Range, Utah, Eric R. Meyer Dec 2014

Normal Fault Block Or Giant Landslide? Baldy Block, Wasatch Range, Utah, Eric R. Meyer

Theses and Dissertations

Understanding the interplay between surficial and tectonic processes in the development of Utah's Wasatch Range is vital to evaluating geologic hazards along the Wasatch Front. Baldy is a large (6.125 km3) block of limestone and sandstone structurally overlying shale on the western flank of Mount Timpanogos. It has been mapped as a downdropped normal fault block of Permian units, but no other trace of such a fault exists along the range. The Baldy block structurally overlies the weak Manning Canyon shale, which has produced a regional geomorphology replete with faceted spurs, landslide scarps and deposits. Structural, bio- and litho-stratigrahic mapping …


The 1852 Banda Arc Mega-Thrust Earthquake And Tsunami In Indonesia, Tsz Man Fisher Dec 2014

The 1852 Banda Arc Mega-Thrust Earthquake And Tsunami In Indonesia, Tsz Man Fisher

Theses and Dissertations

In 1852, a five-minute long earthquake hit the Banda Arc region that was felt over most of Indonesia. It caused uplift of new islands and sent a tsunami across the Banda Sea that reached a height of 8 meters at Banda Neira and was also registered at Ambon, Saparua and other islands. Records of the 1852 earthquake at multiple locations provide the constraints needed to reconstruct the disastrous event through earthquake intensity analysis and numerical modeling of the tsunami. Using tsunami heights and arrival times as the major constraints, best fit numerical models of the tsunami were constructed using Clawpack. …


Compositional Analysis Of Three Clay Artifact Collections From The Southwestern United States, Kathleen R. Kirkham Dec 2014

Compositional Analysis Of Three Clay Artifact Collections From The Southwestern United States, Kathleen R. Kirkham

Theses and Dissertations

This study assessed ways compositional analysis, facilitated by portable X-ray fluorescence technology (PXRF), can be applied in the museum setting to resolve provenance issues and other collections management questions. A major segment of the study evaluated PXRF as a non-invasive geochemical analysis technique to address concerns about whether the resolution of results is sufficient to draw meaningful conclusions. Compositional analysis, mainly facilitated by PXRF, was successfully applied to three clay artifact collections from the southwestern United States. Pottery sherds from Fourmile Ruin were analyzed using PXRF and compared to analyses from invasive wavelength-dispersive XRF and X-ray diffraction techniques. Expanding the …


Linking Land Use And Water Quality Changes In Lake Maumelle Through Benthic Sediment, Dawn Marie Johnson Nov 2014

Linking Land Use And Water Quality Changes In Lake Maumelle Through Benthic Sediment, Dawn Marie Johnson

Theses and Dissertations

Lake Maumelle is a reservoir in Pulaski County, Arkansas that was finished in 1958 for the purpose of supplying potable water to Little Rock and surrounding areas. It is an oligotrophic, monomictic lake with a generously forested watershed. There has been an increase of urbanization in the watershed which may influence the water quality. This research examines the reservoir's sensitivity to land use/land cover change for the lake by analyzing the benthic sediment. By using multidisciplinary methods, cores were examined using mass accumulation rates, grain size analysis, elemental analysis, phase identification, and diatom identification. Those results were then compared to …


The Nature And Origin Of Pebble Dikes And Associated Alteration: Tintic Mining District (Ag-Pb-Zn), Utah, Douglas M. Johnson Nov 2014

The Nature And Origin Of Pebble Dikes And Associated Alteration: Tintic Mining District (Ag-Pb-Zn), Utah, Douglas M. Johnson

Theses and Dissertations

In many ore deposits throughout the world, brecciation often accompanies or occurs in association with mineralization (Sillitoe, 1985). Such is the case in the Tintic Mining District (Ag-Pb-Zn) of north-central Utah, where unique breccia features called pebble dikes occur alongside significant mineralization. Pebble dikes are tabular bodies of breccia, which consist of angular to rounded clasts of quartzite, shale, carbonate, and minor igneous rock cemented in a fine-grained clastic matrix. All clasts now lie above or adjacent to corresponding source rocks. Dikes are thin, typically less than 0.3 m wide to as much as 1 m, and can exceed 100 …


The Relationship Between Environmental Factors And Cyanobacteria Population In Lake Bloomington And Evergreen Lake In Mclean County, Illinois, Matthew Douglas Meyers Oct 2014

The Relationship Between Environmental Factors And Cyanobacteria Population In Lake Bloomington And Evergreen Lake In Mclean County, Illinois, Matthew Douglas Meyers

Theses and Dissertations

This thesis investigates cyanobacteria on two lakes in McLean County, Illinois from the months of August to October. Data was collected every other week.Cyanobacteria are prokaryotes that may be unicellular, colonial or filamentous in form. These cells can be known to be toxic or non-toxic. The factors that control the reproduction of cyanobacteria are the temperature and nutrients of nitrogen and phosphorus. These microorganisms are located in marine and terrestrial settings worldwide. The focus of this study was at two man-made lakes which are Lake Bloomington and Lake Evergreen. Sampling and collection of data was done on two lakes to …


Tectonic Studies Of The Atlantic Margin In The Southeastern United States, Andrew C. Pollack Aug 2014

Tectonic Studies Of The Atlantic Margin In The Southeastern United States, Andrew C. Pollack

Theses and Dissertations

Reanalysis of published seismic and well data from the South Georgia Embayment provides important new constraints on the geologic structure and evolution of the Eastern North American margin. A lower Paleozoic stratigraphic section (Silurian to Devonian) sampled in offshore wells drilled in the late 1970’s, can be correlated continuously along the entire ~250 km N-S length of the BA-3 profile acquired in 1989. Other than gentle warping and minor fault offsets, this Paleozoic section is essentially undeformed, precluding both Paleozoic contractional deformation associated with Appalachian orogeny, or subsequent Mesozoic extensional deformation and magmatism associated with continental rifting and formation of …


Garzón Massif Basement Tectonics: A Geopyhysical Study, Upper Magdalena Valley, Colombia, Kadir Baris Bakioglu Aug 2014

Garzón Massif Basement Tectonics: A Geopyhysical Study, Upper Magdalena Valley, Colombia, Kadir Baris Bakioglu

Theses and Dissertations

The mechanics and kinematics of basement tectonic uplifts, such as the Laramide Rocky Mountain orogeny, remain poorly understood and controversial. The debate continues in part because of the limited number of well-documented present day analogs. The Garzón Massif rising between the Upper Magdalena Valley and the Llanos Basin of Colombia is an active basement uplift with well, seismic, gravity, and magnetic data available. In the past 10 Ma, PreCambrian age granitic rocks of the Garzón Massif have been uplifted and displaced against Cretaceous and Tertiary sediments of the Upper Magdalena Valley along the Garzón fault.

Aerogravimetric data calibrated by well …


Channel Properties Of Fluvial-Tidal Transition, Santee River, Sc, Kyungho Jeon Aug 2014

Channel Properties Of Fluvial-Tidal Transition, Santee River, Sc, Kyungho Jeon

Theses and Dissertations

A range of studies shows that terrestrial and tidal channel dimensions increase in the downstream direction, transitioning seaward from a power function of discharge to an exponential function of distance from the coast. There are also an increasing number of studies on tidal hydrodynamics and sedimentology in channel reaches where river and tidal flows meet. However, there is a dearth of information on the channel form in fluvial-tidal transition, and therefore we have little understanding of what constitutes the fluvial-tidal transition channel, or channel reach. The Santee River in South Carolina is a gently sloping (average 10-5) coastal plain river …


Flow Dynamics In The Transition Zone From Estuarine Tidal To Fluvial Regime In The Santee River, Sc, Usa, Legna M. Torres-Garcia Aug 2014

Flow Dynamics In The Transition Zone From Estuarine Tidal To Fluvial Regime In The Santee River, Sc, Usa, Legna M. Torres-Garcia

Theses and Dissertations

Estuaries are important systems that link fresh, inland waters to oceanic salt water, where they act to deliver large amounts of nutrients, sediments and pollutants into the ocean. Traditionally, the study of estuarine systems has been marked by difficulty owing to the complex hydrodynamics influenced by strong bathymetric changes, changes in tidal range, intricate geomorphology, among other factors; thus beginning to unravel the complexities of estuarine hydrodynamics will help to illuminate the nature of estuaries as well as to provide a foundation for their further study. In this study I focus on the transition zone from tidal to fluvial regime, …


Genes Mediating Cardiac Remodeling During Pregnancy And The Early Post-Partum-Period In Mice, Esam Aljrbi Aug 2014

Genes Mediating Cardiac Remodeling During Pregnancy And The Early Post-Partum-Period In Mice, Esam Aljrbi

Theses and Dissertations

The female heart undergoes adaptive remodeling during pregnancy to compensate for the increased hemodynamic load imposed by the developing fetus. However, unlike a similar adaptive process which occurs under pathological conditions (such as hypertension and valvular heart disease) the cardiac changes observed during hypertrophy associated with pregnancy are reversible. The goal of this study is to identify changes in gene expression associated with pregnancy-induced hypertrophy. We tested the hypothesis that pregnancy-induced physiological hypertrophy has a unique genetic signature, likely due to altered hormone levels, which supports and promotes reversible remodeling. Comparing the gene expression profile associated with physiological remodeling with …


Nitrate Uptake In Central Illinois Streams: A Comparison Along A Transient Storage Gradient, Kristen Lynn Theesfeld Aug 2014

Nitrate Uptake In Central Illinois Streams: A Comparison Along A Transient Storage Gradient, Kristen Lynn Theesfeld

Theses and Dissertations

Transient storage can be influenced by channel morphology. Anthropogenic activities can alter stream morphology by straightening channels, lining channels, or even restoration of previously altered channels. This study focused on whether relative transient storage (RTS) was related to stream type - modified lined, modified unlined, or natural. The study further sought to determine if a greater RTS is correlated to a decrease in percent nitrate-N.

Eight (8) sites, encompassing three (3) different stream types - modified lines, modified unlined, and natural - were studied. Chloride and nitrate tracers were added to streams, and samples were analyzed for tracer concentrations and …


Build-And-Fill Development Of Lower Ismay (Middle Pennsylvanian Paradox Formation) Phylloid-Algal Mounds Of The Paradox Basin, Southeastern Utah, Lincoln H. Reed Aug 2014

Build-And-Fill Development Of Lower Ismay (Middle Pennsylvanian Paradox Formation) Phylloid-Algal Mounds Of The Paradox Basin, Southeastern Utah, Lincoln H. Reed

Theses and Dissertations

Phylloid-algal mounds form heterogeneous hydrocarbon reservoirs in the southeastern portion (Blanding sub-basin) of the Paradox Basin. Well-studied Lower Ismay mounds exposed along walls of the San Juan River gorge in the vicinity of Eight Foot Rapids, the west limb of the Raplee Anticline, and at the classic Honaker Trail locality (southwestern Paradox Basin) have often been cited as outcrop analogs of productive subsurface mounds. Until now, however, there has not been a complete description of the distribution, size, and spacing of outcropping algal mounds at the classic Eight Foot Rapids locality. The Lower Ismay sequence was analyzed in the context …


Tectonics Of Saturn's Moon Titan And Tsunami Modeling Of The 1629 Mega-Thrust Earthquake In Eastern Indonesia, Yung-Chun Liu Jul 2014

Tectonics Of Saturn's Moon Titan And Tsunami Modeling Of The 1629 Mega-Thrust Earthquake In Eastern Indonesia, Yung-Chun Liu

Theses and Dissertations

Chapter 1-2:The Cassini RADAR mapper has imaged elevated blocks and mountains on Titan we term ‘ridges’. Two unresolved problems regarding Titan's surface are still debated: what is the origin of its ridges and was there tectonic activity on Titan? To understand the processes that produced the ridges, in this study, (1) we analyze the distribution and orientation of ridges through systematic geomorphologic mapping and (2) we compare the location of the ridges to a new global topographic map to explore the correlation between elevation and ridges and the implications for Titan's surface evolution. Globally, the orientation of ridges is nearly …


Paterae On Io: Geologic Mapping Of Tupan Patera And Experimental Models, Megan Carolee Decker Jul 2014

Paterae On Io: Geologic Mapping Of Tupan Patera And Experimental Models, Megan Carolee Decker

Theses and Dissertations

Paterae cover approximately 2% of the surface of Io, Jupiter’s volcanically active moon. To understand the formation of these volcano-tectonic depressions we created a geologic map of a key region and compared this map with experimental models for Io paterae. Our mapping region is Tupan Patera, a patera that has experienced recent activity and is a detected hot spot. We identified four primary types of geologic materials: plains, patera floors, flows, and diffuse deposits. We constructed an experimental model to test previous suggestions that paterae may form as volatiles in the silicate crust are vaporized by rising magma, creating instability, …


Wetlands On The Thousand Lake Mountain Mega-Landslide As Paleoclimate Proxies, Ryan Andros Shurtliff Jun 2014

Wetlands On The Thousand Lake Mountain Mega-Landslide As Paleoclimate Proxies, Ryan Andros Shurtliff

Theses and Dissertations

The Windy Ridge mega-landslide in Wayne and Sevier Counties originated in Lates tPleistocene time as established by 14C ages on basal organic-rich clay and peat sediment from bogs that developed on the slide. The contact depth between bog and landslide was estimated using high-resolution seismic reflection to find the thickest sediment. Four bogs were cored at their depocenters, and organic material at the slide contact was used for age determinations. The oldest bog sediments ages are 10,600 ± 46, 10,556 ± 34, 12,511 ± 134, and 12,886 ± 91 calibrated years BP. Ages represent two sliding events. First, at the …


Sand Sea Extents And Sediment Volumes On Titan From Dune Parameters, Karl D. Arnold Jun 2014

Sand Sea Extents And Sediment Volumes On Titan From Dune Parameters, Karl D. Arnold

Theses and Dissertations

Linear dunes are one of the most abundant and important features on the surface of Titan. We present a model for estimating the volume of dune sediment using the area coverage of Titan's sand seas along with dune widths, spacings, and heights. This helps to reveal local sediment transport and deposition. We refine global dune area estimates from Cassini SAR (Synthetic Aperture RADAR) of 20 million km2 or 24 ± 3% of Titan's surface based on ~50% Cassini RADAR global coverage. Additionally, the global area of sand seas is estimated from a joint analysis of Cassini SAR and ISS (Imaging …


Along Strike Variability Of Thrust-Fault Vergence, Scott Royal Greenhalgh Jun 2014

Along Strike Variability Of Thrust-Fault Vergence, Scott Royal Greenhalgh

Theses and Dissertations

The kinematic evolution and along-strike variation in contractional deformation in overthrust belts are poorly understood, especially in three dimensions. The Sevier-age Cordilleran overthrust belt of southwestern Wyoming, with its abundance of subsurface data, provides an ideal laboratory to study how this deformation varies along the strike of the belt. We have performed a detailed structural interpretation of dual vergent thrusts based on a 3D seismic survey along the Wyoming salient of the Cordilleran overthrust belt (Big Piney-LaBarge field). The complex evolution of the thrust faults that parallel the overthrust belt is demonstrated by the switching of the direction of thrust …


A New Geophysical Strategy For Measuring The Thickness Of The Critical Zone, Johnathan R. Yaede Jun 2014

A New Geophysical Strategy For Measuring The Thickness Of The Critical Zone, Johnathan R. Yaede

Theses and Dissertations

Estimates of the depth and variation of lateritic weathering profiles are especially important in tropical areas such as Oahu, HI. Shear-wave velocity data were obtained by a new application of Multi-channel Analysis of Surface Waves (MASW) to map the base of the critical zone, to show variations in the LWP, and to derive weathering rates. The MASW technique proved highly capable of imaging the base of the critical zone, confirmed by lithological well data and direct field measurements. Profile thickness can be obtained without drilling, which has applications in engineering and geochemical studies. The measured rate of advance of the …


Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii Jun 2014

Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii

Theses and Dissertations

The late Middle Jurassic (Callovian) Entrada Sandstone has been divided into two general facies associations consisting primarily of eolian sandstones in eastern Utah and "muddy" redbeds in central Utah. Sedimentary structures within the redbed portion are explained by the interfingering of inland sabkha, alluvial, and eolian depositional systems. A complete succession from the most basinward facies to the most terrestrial facies in the Entrada Sandstone consists of inland sabkha facies overlain by either alluvial or eolian facies. Where both alluvial and eolian facies interfinger, alluvial facies overlain by eolian facies is considered a normal succession. Sequence boundaries, often identified by …