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Full-Text Articles in Physical Sciences and Mathematics

Pre-Stack Seismic Inversion And Amplitude Variation With Offset (Avo) Attributes As Hydrocarbon Indicators In Carbonate Rocks: A Case Study From The Illinois Basin, Jacob T. Murchek Jan 2021

Pre-Stack Seismic Inversion And Amplitude Variation With Offset (Avo) Attributes As Hydrocarbon Indicators In Carbonate Rocks: A Case Study From The Illinois Basin, Jacob T. Murchek

Browse all Theses and Dissertations

Amplitude anomalies in pre-stack seismic data have widely been used in the oil and gas industry as a risk analysis tool when exploring for hydrocarbons. AVO analysis is most often applied to poorly consolidated Tertiary rocks due to the compressibility of these strata when natural gas and porosity are present. In contrast, well-lithified carbonate rocks are less prone to producing a pre-stack amplitude response due to the rigidity of their frame. Pre-stack seismic data of a 2-D seismic profile were conditioned and interpreted to identify amplitude variation with offset (AVO) attributes corresponding to the presence of hydrocarbons within the North …


The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman Jan 2021

The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman

Senior Independent Study Theses

Discrepancies between farmers’ and scientists’ knowledge systems and experiences have long prevented the success and mutual beneficiality of collaborative research efforts between these two groups. The development of agricultural technologies, such as portable X-ray fluorescence (PXRF) for the analysis of soil cation exchange capacity in the field, creates a promising overlap point for farmers and scientists to cooperatively study issues within their sociocultural context and with access to institutional resources. In this study, the generation of an in-field PXRF method in collaboration with Colorado farmers helps to provide a prospective model for scientists and farmers looking to use collaborative research …


Structural And Thermochronologic Evidence Of Paleogene-Neogene Faulting And Exhumation Of The Klamath Mountain Province, Taylor C. Team Jan 2021

Structural And Thermochronologic Evidence Of Paleogene-Neogene Faulting And Exhumation Of The Klamath Mountain Province, Taylor C. Team

Cal Poly Humboldt theses and projects

The Klamath Mountains Province (KMP), located at the southern end of the forearc of the Cascadia Subduction Zone, displays a distinct topographic and geologic signature. Compared to the forearc in the north, the KMP comprises Paleozoic-Mesozoic basement rocks with relatively high modern elevation and relief. This study investigates the pattern of rock cooling in the KMP by using thermochronology on plutons exhumed by faults and plutons outside of mapped faults. In this study, I target three regions in the KMP: the Ashland pluton offset by the Siskiyou Summit fault in the northeast KMP, the Grayback pluton in the northwest KMP, …


Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli Jan 2021

Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hydrocarbon exploration in unconventional reservoirs is highly risky due to the nature of the reservoirs and the variability in fractures and reservoir geomechanical properties in the subsurface. The reservoir needs to be fully characterized to avoid any complication such as frac hit, wellbore failure, blowout, or even a dry hole. The Clearfield reservoir produces an exceptionally low amount of gas, compared to the neighboring region in the proximity, which has been poorly understood. This raises the question as to what causes the reservoir to have low productivity.

This study focuses on the natural fracture characterization using high-quality 3D seismic signal …


Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw Ms Jan 2021

Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw Ms

Graduate Student Theses, Dissertations, & Professional Papers

Studying cordierite orthoamphibole gneisses (COG) from five different mountain ranges across the Montana Metasedimentary Terrane (MMT) of the Wyoming Province offers a unique opportunity to elucidate the enigmatic origins and petrogenesis of the lithology in addition to gaining a further understanding of Precambrian crustal assembly processes. Geochemical analyses suggest that COG originates from a basalt that underwent metasomatic alteration, likely via seawater, prior to metamorphism. Moreover, COG is considered to represent oceanic crust that was part of the epicontinental sea adjacent to the Wyoming Province before collision with the Medicine Hat Block. Field observations of associated lithologies such as marbles, …


Sediment Provenance Of Tsunami Deposits: Implications For Assessing The Relative Intensity Of Paleotsunamis From The Sendai Coastline Of Japan, Tiffany Otai Dec 2020

Sediment Provenance Of Tsunami Deposits: Implications For Assessing The Relative Intensity Of Paleotsunamis From The Sendai Coastline Of Japan, Tiffany Otai

Master's Theses

The 2011 Tohoku tsunami impacted the northeastern coast of Japan and caused unexpected damages due to the underestimation of this type of hazard. Of particular importance is the fact that geologic evidence for a predecessor event, the Jogan tsunami (CE 869), could have forecasted the severity of the 2011 Tohoku event. While the timing of tsunamis is important for effective hazard mitigation, outside of the 2011 Tohoku event, the intensity of past tsunamis remains unclear. To understand paleotsunami intensity, it is important to document characteristics of modern analogues like the 2011 event. This study utilizes surface distributions of foraminifera from …


The Multidisciplinary Enrichment Of Undergraduate Environmental Geology Students From International Summer Programs. Case Study: Summer 2019 3mugis, Russia, Ruslana Baker, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer Oct 2020

The Multidisciplinary Enrichment Of Undergraduate Environmental Geology Students From International Summer Programs. Case Study: Summer 2019 3mugis, Russia, Ruslana Baker, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer

Publications and Research

Hosted by the People’s Friendly University of Russia (RUDN), the Modeling, Monitoring, and Managing of Urban Green Infrastructure (3MUGIS) summer program was organized by the collaboration of the New York City Urban Soil Institute (NYC-USI), City University of New York – Brooklyn College, and under the auspices of the International Union of Soil Sciences (IUSS). The program consisted of one-week lecture sessions and two-weeks of fieldwork across five bioclimatic zones, ranging from the sub-arctic tundra of the Kola Peninsula to the Southern Steps of Rostov, Black Sea. Faculty and guest lecturers included scientists with various expertise from Germany, USA, Russia, …


Mineralogy, Dexter Perkins Oct 2020

Mineralogy, Dexter Perkins

Open Educational Resources

This is a beta version of an open access textbook on Mineralogy, current as of October 2020. For the most recently updated live version please see: https://opengeology.org/Mineralogy/


Teaching With Digital 3d Models Of Minerals And Rocks, Graham Dm Andrews, Gabrielle Labishak, Sarah Brown, Shelby L. Isom, Holly Danielle Pettus, Trevor Byers Oct 2020

Teaching With Digital 3d Models Of Minerals And Rocks, Graham Dm Andrews, Gabrielle Labishak, Sarah Brown, Shelby L. Isom, Holly Danielle Pettus, Trevor Byers

Faculty & Staff Scholarship

The disruption to geoscience curricula due to the COVID-19 pandemic highlights the difficulty of making mineral and rock samples accessible to students online rather than through traditional lab classes. In spring 2020, our community had to adapt rapidly to remote instruction; this transition amplified existing disparities in access to geoscience education but can be a catalyst to increase accessibility and flexibility in instruction permanently. Fortunately, a rich collection of 3D mineral and rock samples is being generated by a community of digital modelers (e.g., Perkins et al., 2019).


Visualizing Effects Of Changing Base Level On Tributary Resources In Lake Powell Reservoir, Madeline Friend Aug 2020

Visualizing Effects Of Changing Base Level On Tributary Resources In Lake Powell Reservoir, Madeline Friend

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Lake Powell reservoir is the second-largest reservoir in the United States. As climate change reduces watershed runoff in the Colorado River Basin, questions arise about the management and even existence of Lake Powell. If lake levels continue to drop, what will the emerging canyon look like and what value will we assign it? Lake Powell traps all incoming fine sediment from the Colorado River, the San Juan River, and many smaller tributaries. What is the fate of this sediment under falling reservoir levels and how will it influence other resources? To support a robust public discourse, we provide an immersive …


Geology, Soils And Climate Of The Margaret River Wine Region, Peter J. Tille, Angela Stuart-Street, Peter S. Gardiner Aug 2020

Geology, Soils And Climate Of The Margaret River Wine Region, Peter J. Tille, Angela Stuart-Street, Peter S. Gardiner

All other publications

This report is an extract from the broader description and analysis of the Geology, soils and climate of Western Australia's wine regions. It expands on the brief descriptions in the second edition of 'Viticulture' (Coombe & Dry 2004) concerning the soils and landscapes of Western Australia’s main wine growing regions. We have tailored this report extract to the specific needs of the Margaret River wine region. It contains local soil names and soil-landscape zones and systems maps.

The wine industry recognises the importance of giving customers an understanding of the vines’ environment and how that may influence wine character …


A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell Jun 2020

A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell

Theses and Dissertations

The influence of human activity on surrounding environments is an important field of research. With respect to aquatic settings, lacustrine deposits provide excellent proxies of environmental change since the sediment accumulates at a relatively constant rate, recording environmental change. This study employs isotopic, mineral, and chemical records from Farmington Bay freeze cores, in particular δ13C, δ15N, and 210Pb isotopes as well as phosphorus level fluctuation and trace metal analysis. In particular, 210Pb isotopes permit estimation of the age of sediment with depth and δ15N, δ13C, and concentration of P provides a record of changing nutrient sources and level of eutrophication. …


Uas-Based Tracking Of The Santiaguito Lava Dome, Guatemala, Edgar U. Zorn, Thomas R. Walter, Jeffrey B. Johnson, René Mania May 2020

Uas-Based Tracking Of The Santiaguito Lava Dome, Guatemala, Edgar U. Zorn, Thomas R. Walter, Jeffrey B. Johnson, René Mania

Geosciences Faculty Publications and Presentations

Imaging growing lava domes has remained a great challenge in volcanology due to their inaccessibility and the severe hazard of collapse or explosion. Changes in surface movement, temperature, or lava viscosity are considered crucial data for hazard assessments at active lava domes and thus valuable study targets. Here, we present results from a series of repeated survey flights with both optical and thermal cameras at the Caliente lava dome, part of the Santiaguito complex at Santa Maria volcano, Guatemala, using an Unoccupied Aircraft System (UAS) to create topography data and orthophotos of the lava dome. This enabled us to track …


Band Extension And Possible Ridge Compression On Europa, Sarah Chinski May 2020

Band Extension And Possible Ridge Compression On Europa, Sarah Chinski

Macalester Journal of Physics and Astronomy

Jupiter's icy moon Europa has captivated and perplexed the scientific community since the discovery of its global liquid water ocean. Over the course of several missions to the Jovian system, high-resolution observations of Europa have determined that there are spreading zones where new crust is created, similar to the mid-ocean spreading tectonic process we observe on Earth. These features, known as bands, have symmetric hills and valleys, indicating brief events of activity where material from the interior is exuded through a central crack, and solidifies on both sides, creating two positive topography. Recently, Europan scientists have been questioning how these …


Experiments To Synthesize Soft-Sedimentary Deformation And Clastic Dikes, Chelsi K. Howard May 2020

Experiments To Synthesize Soft-Sedimentary Deformation And Clastic Dikes, Chelsi K. Howard

2020 Symposium Posters

Clastic dikes are intrusions of sediments into layers of other sedimentary strata that are found in various places across eastern Washington. Three notable sites include Burlingame Canyon in Touchet, WA, Tucannon Valley near Starbuck, WA and Campion Park in Spokane, WA. Clastic dikes are thought to be formed by either overburden stress or from seismic activity. In eastern WA, the dikes were formed by large overburden pressure and seismic-like forces caused by cataclysmic floods that washed over eastern WA (known as the Missoula floods). We recreated this environment by layering saturated sand below and on top of kaolinite clay, and …


Impact Of Compactive Effort On Soil Strength Of Glacial Lake Columbia Soils, Alexander M. Navarra, Dwight Hendrickson, Jaremy Shaw May 2020

Impact Of Compactive Effort On Soil Strength Of Glacial Lake Columbia Soils, Alexander M. Navarra, Dwight Hendrickson, Jaremy Shaw

2020 Symposium Posters

Glacial Lake Columbia (GLC) existed from 15,550 (+/- 450) to 13,050 (+/- 650) years ago (Atwater, 1986) as a result of the Okanagan Lobe of the Cordilleran Ice Sheet damming the Columbia River near present-day Grand Coulee Dam. The lake deposited a fine-grained basal layer that had interbeds of coarse Missoula Flood deposits and later lake deposits above. Because these GLC deposits are present around most of the Spokane area, they are important to civil engineering and development. We sampled the basal layer of GLC soils from the Peone Prairie, WA. We performed prerequisite testing before the main experiment, with …


Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn May 2020

Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn

Graduate Theses/Dissertations

Lascar volcano is one the most active volcano in the Central Volcanic Zone of the Andean Cordillera, with 36 Holocene eruptions including a VEI 4 eruption in April 1993. Activity has not been consistent throughout time, and therefore, the processes behind it are poorly understood. Lascar volcano has cyclic behavior and has had four stages of activity, each of which had a unique eruptive style and product composition. Stage I (<43 >ka) had primarily mafic andesite lavas erupted effusively from a stratocone. Stage II initiated with dome building events ESE of the original vent and culminated in the 26.45 ka …


Testing A Drone-Based Magnetic Field Surveying System, Erik Jacobson, Irina Filina Apr 2020

Testing A Drone-Based Magnetic Field Surveying System, Erik Jacobson, Irina Filina

UCARE: Research Products

Aeromagnetic surveys are conducted by geoscientists to study subsurface geologic structures, such as faults. This type of survey uses a magnetometer mounted upon an airborne vehicle to collect magnetic field data. Magnetic anomalies are caused by variations in subsurface geology, namely in magnetic properties of subsurface rocks. Jacobson and Filina (2019) reported on the development of a new low cost drone, based magnetic field surveying system by the UNL Geophysics Team. This drone-based magnetic system is capable of collecting high resolution data at low speeds and low altitudes. The current study focuses on testing this system by conducting two flights …


Quantifying Water Content In Olivine From North Carolina Dunites Using Fourier-Transform Infrared Spectroscopy, Thomas Byars Apr 2020

Quantifying Water Content In Olivine From North Carolina Dunites Using Fourier-Transform Infrared Spectroscopy, Thomas Byars

Student Scholars Day Posters

The focus of this study is to quantify the water content in grains of the mineral olivine collected from the Buck Creek Ultramafic Suite–a fragment of ancient ocean crust emplaced into the Appalachian Mountains in North Carolina. Previous work on these samples includes Electron Back Scatter Diffraction (EBSD) analysis. EBSD data can constrain temperature and stress conditions of olivine deformation under different levels of hydration. The water in olivine was analyzed using a Fourier-Transform Infrared Spectroscopy (FTIR) at the North Carolina Museum of Natural Science. The olivine grains are doubly polished in preparation for FTIR analysis. The machine scans the …


Geology Of Nacogdoches, Texas: Texas Academy Of Science March 1, 2020, R. Larell Nielson, Mike Read, Mindy Faulkner, Hannah C. Chambers, Jessica O'Neal Feb 2020

Geology Of Nacogdoches, Texas: Texas Academy Of Science March 1, 2020, R. Larell Nielson, Mike Read, Mindy Faulkner, Hannah C. Chambers, Jessica O'Neal

Faculty Publications

No abstract provided.


The Hydrostatics And Hydrodynamics Of Prominent Heteromorph Ammonoid Morphotypes And The Functional Morphology Of Ammonitic Septa, David Joseph Peterman Jan 2020

The Hydrostatics And Hydrodynamics Of Prominent Heteromorph Ammonoid Morphotypes And The Functional Morphology Of Ammonitic Septa, David Joseph Peterman

Browse all Theses and Dissertations

Ammonoid cephalopods have chambered shells that regulated buoyancy. The morphology of their shells strongly influenced the physical properties acting on these animals during life. Heteromorph ammonoids, which undergo changes in coiling throughout ontogeny, are the focus of this dissertation. The biomechanics of these cephalopods are investigated in a framework involving functional morphology, paleoecology, and possible modes of life. Constructional constraints were investigated for the marginally-corrugated septal walls within the chambered ammonoid shell. These constraints governed the positive relationship between septal complexity and terminal size. Furthermore, increased septal complexity facilitated liquid retention via surface tension. More complex septa would have increased …


Geochemical Analysis And Heat-Treatment Of Natural Sapphires From Madagascar And Tanzania In Oxidizing And Reducing Conditions, Lukas Karuza, Dr. Michael B. Wolf, Brian Konecke Phd Jan 2020

Geochemical Analysis And Heat-Treatment Of Natural Sapphires From Madagascar And Tanzania In Oxidizing And Reducing Conditions, Lukas Karuza, Dr. Michael B. Wolf, Brian Konecke Phd

Geology: Student Scholarship & Creative Works

Natural or synthetic sapphires can be heat-treated to improve the clarity by removing “silk” (inclusions) and to change color by introducing color-inducing elements (i.e., chromophores) into the lattice structure or changing their valency. Due to these reasons, sapphires can be heat-treated to increase their monetary value. Twenty natural blue (C1), 20 green (C2), and 20 clear (C3) sapphires from Madagascar and Tanzania were heat-treated in a muffle furnace in oxidizing and reducing conditions, from 1200 to 1600℃, for 10-hour soak time. In total, 5 experiments were conducted in which soak time remained constant: experiment 1 was performed at 1200℃, exp. …


Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison Jan 2020

Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison

Mahurin Honors College Capstone Experience/Thesis Projects

Geochemical fluxes in aqueous studies are an essential component of research to understand weathering and changes in a hydrologic system. These data can indicate any discrepancies, outliers, or gradual changes in a water environment to gain information on pollutants, carbon cycles, biological input, etc. Glacial melt is the majority of the surface water present throughout the country. The melting amount is increasing with the temperatures, which can be monitored by the changes in geochemical flux during increased discharge in glacial rivers. A high-resolution data set of Sόlheimajökull Glacier in Iceland was used to determine how changing climatic conditions for the …


Fluvial Sedimentology And Architecture Of Two Latest Devonian Lower Huntley Mountain Formation Outcrops, North-Central Pennsylvania, Usa, Evan W. Filion Jan 2020

Fluvial Sedimentology And Architecture Of Two Latest Devonian Lower Huntley Mountain Formation Outcrops, North-Central Pennsylvania, Usa, Evan W. Filion

Honors Theses

Thick successions of river deposits accumulated in the north-central Pennsylvania region of the Appalachian foreland basin during Late Devonian time (~380-360 Ma). The properties and morphologies of these paleorivers are not well characterized. Latest Devonian tectonic, climatic, and eustatic controls on river dynamics and basin infilling also remain unclear. This study assesses the sedimentology, facies architecture, paleochannel depths, and grain size of a 133 m thick section of fluvial strata exposed across two outcrops, Blossburg South (older) and Blossburg West (younger), mapped as lower Huntley Mountain Formation near Blossburg, Pennsylvania. Field-based lithofacies observations, high-resolution panoramic photography, terrestrial lidar scanning, and …


Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco Jan 2020

Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco

Williams Honors College, Honors Research Projects

Many celestial bodies within our solar system may have habitable environments due to the presence of liquid water. Europa, one of Jupiter’s moons, may be habitable because of its liquid ocean and other potentially biologically favorable conditions. The ocean on Europa is hypothesized to contain large amounts of oxidants and low pH due to the radiolytically processed icy ocean shell. This suspected environment on Europa is similar to the composition of acid mine drainage on Earth, which can house microbial communities in environments of extreme acidity. Similar chemical reactions in Europa’s ocean may occur to produce the appropriate reduction-oxidation gradients …


Quantifying Contributions To The Variance Of Permeability And Porosity Within The Western Belt Sandstones Of The Cypress Formation, Illinois Basin, Nathaniel Frederick Dulaney Jan 2020

Quantifying Contributions To The Variance Of Permeability And Porosity Within The Western Belt Sandstones Of The Cypress Formation, Illinois Basin, Nathaniel Frederick Dulaney

Browse all Theses and Dissertations

One of the strategies for reducing the emission of the greenhouse gas carbon dioxide (CO2) and mitigating its accumulation into the Earth’s atmosphere is geologic sequestration (GSCO2). This process might be paired with enhanced oil recovery (EOR) within depleted oil reservoirs to provide an economic incentive for GSCO2. Heterogeneity within reservoirs (e.g. spatial differences in entry pressure, permeability, and porosity) can exert significant influence on the dynamics of fluid flow during EOR and GSCO2, and thus on the ultimate success of GSCO2-EOR. The Western Belt sandstones of the Cypress Formation in the Illinois Basin are candidate reservoirs for GSCO2-EOR. Heterogeneity …


Paleoecology Of Bivalves In The Carmel Formation (Middle Jurassic, Bajocian) Of Utah, Evan L. Shadbolt Jan 2020

Paleoecology Of Bivalves In The Carmel Formation (Middle Jurassic, Bajocian) Of Utah, Evan L. Shadbolt

Senior Independent Study Theses

The Carmel Formation of the Middle Jurassic has many mysteries. One of these enigmas is its bivalves. The formation contains the famous oyster balls called ostreoliths. Despite bivalves making up 80 percent of the fossils found in the Carmel Formation, it is not understood how the bivalves lived in this community. The formation is located in southwestern and central Utah. It was deposited when an epicontinental seaway covered most of Utah. The paleoclimate of Utah was hot and dry, which meant that the environment was evaporite heavy. This also meant that the seawater at the southernmost extent of the seaway …


Paleoenvironments Containing Coryphodon In The Fort Union And Willwood Formations Spanning The Paleocene-Eocene Thermal Maximum (Petm), Bighorn Basin, Wyoming, Emily N. Randall Jan 2020

Paleoenvironments Containing Coryphodon In The Fort Union And Willwood Formations Spanning The Paleocene-Eocene Thermal Maximum (Petm), Bighorn Basin, Wyoming, Emily N. Randall

Senior Independent Study Theses

Preliminary data point toward a new hypothesis in which Coryphodon lived in wetter habitats before the Paleocene-Eocene Thermal Maximum (PETM), but was able to adapt to drier habitats in order to survive post-PETM. Early Paleogene nonmarine strata are extensively exposed in the Bighorn Basin of northwestern Wyoming. The Fort Union and Willwood Formations represent alluvial deposition within a Laramide Basin formed from the Paleocene through early Eocene. Therefore, the basin is an ideal place to study the local effects of the PETM, a rapid global warming event that occurred about 55.5 million years ago at the Paleocene–Eocene boundary. During this …


Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard Jan 2020

Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

Data from thousands of test-hole and well logs were interpreted to improve understanding and management of the High Plains aquifer in a three-county study area adjacent to the Big Bend reach of the Platte River. Five principal conclusions resulted from these interpretations: (1) the extent of Neogene Ogallala deposits beneath the study area is different than previously mapped; (2) a large paleovalley incised into Cretaceous bedrock probably cuts across Kearney and Adams counties and may be the course of the ancestral Platte River prior to formation of the Big Bend; (3) a groundwater mound created by irrigation canals artificially raises …


Supra-Salt Syndepositional Folding Within The Jurassic Morrison Formation, Big Gypsum Valley, Colorado, Alondra Soltero Jan 2020

Supra-Salt Syndepositional Folding Within The Jurassic Morrison Formation, Big Gypsum Valley, Colorado, Alondra Soltero

Open Access Theses & Dissertations

The Paradox Basin, along the Utah and Colorado border, exposes salt diapirs that form elongate "salt walls". Most exposures of sediments that were deposited during salt movement are hundreds of meters from the contacts. However, in the southeastern part of the Gypsum Valley diapir, a set of tight folds within the Jurassic Morrison Formation are preserved along the diapir margins where they overlie salt. These are best exposed at the southeastern end of Big Gypsum Valley. Previous interpretations suggested that the Morrison Formation folding and faulting occurred during dissolution of the diapir. However, field mapping reported here reveals that the …