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Geomechanical Study Of Rock Properties In The Kafr El-Sheikh Formation At Sapphire Field, West Delta Deep Marine, Egypt, Moustafa Mohamed Ahmed Attia, Ali El-Sayed Farag, Mahmoud Y. Zein El-Din 2024 Halliburton World Wide Limited Company, Kuwait

Geomechanical Study Of Rock Properties In The Kafr El-Sheikh Formation At Sapphire Field, West Delta Deep Marine, Egypt, Moustafa Mohamed Ahmed Attia, Ali El-Sayed Farag, Mahmoud Y. Zein El-Din

Al-Azhar Bulletin of Science

Numerous challenges were encountered during the drilling operations conducted at the Sapphire oilfield. Instances of stuck pipe, wellbore instability, breakouts, and washouts have been documented in many wells within this field, resulting in unproductive time and additional expenditures. To mitigate these challenges, it is important to conduct a one-dimensional geomechanical model to get a viable resolution. This entails the creation of three primary in situ stress profiles and the assessment of mechanical characteristics of the geological formations. The primary focus of this investigation was to ascertain the mechanical characteristics of the rock. Therefore, this work offers great input while building …


Searching For The Hyperobject: Crystals As Transscalar Vehicles, Jay Costello 2024 Rhode Island School of Design

Searching For The Hyperobject: Crystals As Transscalar Vehicles, Jay Costello

Masters Theses

When I touch the street outside my house, I'm touching Los Angeles—a contiguous vector of material bisecting a continent. A slab, a stone, dust and oil, a googolplex of tightly packed anisotropic particles... At nightfall, I sneak to the edge of the highway and break off a piece. 'What does it mean for a worm to be aware of the scale of the planet?' Bruno Latour's evocative questioning of scalar jumps prompts an existentialism that places me somewhere between the hyperlocal and the massively distributed. Like a cosmic traveler floating through the universe, I feel adrift. I look around, grasping …


Mantle Sources And Geochemical Evolution Of The Picture Gorge Basalt, Columbia River Basalt Group, Emily B. Cahoon, Martin J. Streck, Richard W. Carlson, Ilya N. Bindeman 2024 Oregon State University

Mantle Sources And Geochemical Evolution Of The Picture Gorge Basalt, Columbia River Basalt Group, Emily B. Cahoon, Martin J. Streck, Richard W. Carlson, Ilya N. Bindeman

Geology Faculty Publications and Presentations

The Columbia River Basalt Group (CRBG) is the youngest continental flood basalt province, proposed to be sourced from the deep-seated plume that currently resides underneath Yellowstone National Park. If so, the earliest erupted basalts from this province, such as those in the Picture Gorge Basalt (PGB), aid in understanding and modeling plume impingement and the subsequent evolution of basaltic volcanism. Using geochemical and isotopic data, this study explores potential mantle sources and magma evolution of the PGB. Long known geochemical signatures of the PGB include overall large ion lithophile element (LILE) enrichment and relative depletion of high field strength elements …


Extreme Heat & Public Perception In Portland, Oregon: Evidence Of A Compounding Vulnerability Effect For Climate Hazards, Brianne Suldovsky, Molly Baer Kramer, Jonathan Fink 2024 Portland State University

Extreme Heat & Public Perception In Portland, Oregon: Evidence Of A Compounding Vulnerability Effect For Climate Hazards, Brianne Suldovsky, Molly Baer Kramer, Jonathan Fink

Geology Faculty Publications and Presentations

Extreme heat events are a global public health threat, and the frequency of these events are projected to increase significantly in the coming decades. Responding to extreme heat requires that municipalities communicate with public audiences. Generally speaking, risk communication and public engagement efforts are more effective when they are responsive to current risk perception trends. This social scientific study examines extreme heat risk perceptions, emergency response needs, and level of trust in first responders among residents of the Portland (OR) Metro Area. Using quantitative survey data, it demonstrates the compounding influence of three previously identified vulnerability indicators–poverty, disability, and race–on …


Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik 2024 University of Nebraska - Lincoln

Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik

Conservation and Survey Division

No abstract provided.


Data From: Interweaving Recurring Slope Lineae On Mars: Do They Support A Wet Hypothesis?, Daniel P. Mason, Louis A. Scuderi 2024 University of New Mexico

Data From: Interweaving Recurring Slope Lineae On Mars: Do They Support A Wet Hypothesis?, Daniel P. Mason, Louis A. Scuderi

Earth and Planetary Sciences Faculty and Staff Publications

This is a metadata only access point for the referenced dataset hosted in the Dryad data repository. The following abstract relates to the dataset that is available through Dryad.

Included in these supplementary materials is a manuscript citation and manuscript keywords for the manuscript “Interweaving Recurring Slope Lineae on Mars: Do They Support a Wet Hypothesis?”, as submitted to the scientific journal Icarus. Also included are two JP2 image files, a digital terrain model (DTM) file, two shapefiles, and forty-eight CSV files that all collectively detail data relating to channel counts and sinuosity measurements for Martian hillslope features known as …


The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, JORDAN WRIGHT 2024 Southern Methodist University

The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright

Earth Sciences Theses and Dissertations

This thesis presents new data on the origin of the Western Iron Ore Group (W-IOG), a Paleoarchean succession deposited on sialic rocks of the Singhbhum Craton. U-Pb ages from zircons from a tuff overlying the Lower Shales just below a banded iron formation (BIF) pin the age of the section to 3.39 Ga. Unconformably overlying the whole IOG section is the Darjing Group, which contains the Birtola Sandstone (on the basis of this work, now estimated to be 2.35 Ga). The lack of penetrative deformation and low-grade metamorphism makes these rocks excellent subjects for combined radiogenic and stable isotope studies. …


Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck 2024 Portland State University

Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck

Student Research Symposium

The Mahogany Mountain-Three Fingers Rhyolite Field (MM-TFrf) in southeastern Oregon, associated with mid-Miocene rhyolite activity and Columbia River flood basalts, has been the subject of geological scrutiny. Previous studies proposed separate origins for the tuff of Leslie Gulch (LGT) and Spring Creek, but Benson and Mahood (2006) suggested a single ignimbrite event at 15.8 Ma, prompting a reassessment of MM-TFrf's history. This research focuses on LGT, investigating textural disparities between welded and non-welded tuff formations. Petrographic examinations delve into the transformation stages of pyroclastic tuff deposition, revealing the dynamic influences of volcanological and magmatic processes on welded and non-welded tuff …


Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan 2024 Portland State University

Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan

Student Research Symposium

As the Pacific Northwest climate changes, extreme weather, such as intensifying storms, and a shift in the type of precipitation experienced with warmer winters causing more precipitation to fall as rain instead of snow, may lead to an increased frequency of landslides. There have been several recent landslides in Portland, noticeable to the public, particularly in areas of high elevation such as Council Crest, which stands at 1,073 feet. Additionally, residents of neighboring homes have observed changes in the landscape, including those on private properties. To better safeguard both public and private property, comprehensive research and mitigation efforts are required. …


Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys 2024 Montana Technological University

Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys

Graduate Theses & Non-Theses

In this study, stress and strain measurements from unconfined compression tests were used to determine the peak stress, yield stress, Young’s modulus, and Poisson’s ratio of 20 specimens representing three lithologies (sandstone, norite, and argillite-quartzite mix) from Idaho and Montana. Along with traditional strength and deformation parameters, crack initiation (CI) and crack damage (CD) values were also interpreted, corresponding to the stress levels associated with the formation and coalescence of microcracks as a specimen is exposed to increasing stress levels. Acoustic emissions (AE) data were collected along with traditional stress-strain data as this has become a popular method for interpreting …


Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown 2024 DePauw University

Characterizing Potentially Harmful Environmental Legacy Issues Within A Declining Midwest City: A Street Sediment Study Of Northeastern Terre Haute, Indiana, Katelyn Adams '24, Ken Brown

Senior Research Symposium

Urban settings face unprecedented environmental challenges that include legacy issues as well as emerging pollution problems (e.g., micro-plastics) that continually impact the public health of its communities. Determining the baseline abundances of potentially harmful contaminants in soil, sediment, air, and water is essential to protecting residents. This study examines anthropogenic pollution in street sediments collected from three neighborhoods located in northeast Terre Haute, Indiana. Using stereomicroscopy, SEM/EDS, pXRF analyses, and geospatial analysis (GIS), the goal of this work is to characterize the types of pollutants present and place important constraints on their potential sources.

Stereomicroscopy on nine street sediment samples …


Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24 2024 DePauw University

Dating The Ste. Genevieve Limestone In West-Central Indiana Using Sr-Isotope Stratigraphy, Claire Wolfe '24

Senior Research Symposium

A section of Mississippian limestone is exposed in quarry walls at the DePauw Nature Park in Greencastle, Indiana, but its precise age is not known. This research project aimed to date the exposed wall using 87Sr/86Sr isotopic ratios to determine the absolute age. Ten samples of brachiopods and ooids were collected at various levels along the stratigraphic column. Isotope ratios were measured in these samples at ALS Scandinavia using a Neptune Plus MC-ICP-MS. Those ratios were then placed on a LOESS seawater Sr-isotope curve (McArthur, 2020) to determine the absolute age range for each sample. Whereas several samples were contaminated …


Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill 2024 Smith College

Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill

Geosciences: Faculty Publications

The beginning of the Phanerozoic saw two biological events that set the stage for all life that was to come: (a) the Cambrian Explosion (the appearance of most marine invertebrate phyla) and (b) the Great Ordovician Biodiversification Event (GOBE), the subsequent substantial accumulation of marine biodiversity. Here, we examine the current state of understanding of marine environments and ecosystems from the late Ediacaran through the Early Ordovician, which spans this biologically important interval. Through a compilation and review of the existing geochemical, mineralogical, sedimentological, and fossil records, we argue that this interval was one of sustained low and variable marine …


Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue 2024 Utah State University

Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue

All Graduate Theses and Dissertations, Fall 2023 to Present

Geoscience has a known diversity problem, specifically a participation gap of ethnic minority representation, and it is especially severe regarding Native American representation. To address this participation gap, an identity gap needs to be addressed first. Native students need to visualize themselves as geoscientists before they can commit to geoscience programs and careers. This project uses a hands-on, place-based learning activity as an opportunity for Native students to better see themselves as geoscientists.

A portable rainfall simulator was constructed, calibrated, and refined for use in teaching concepts about rainfall, runoff, and erosion. It was employed in place-based learning exercises with …


The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann 2024 The University of Southern Mississippi

The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann

Master's Theses

This study investigates gabbro-cored oceanic core complexes in the slow-spreading Mid-Atlantic Ridge (MAR) and the ultraslow spreading Southwest Indian Ridge (SWIR). Dikelets are a texture found in thin section samples from these systems that form as a result of crystal-plastic deformation. Thin section samples from the Atlantis Massif, MARK Area, and 13˚-15˚ North of the MAR and the Atlantis Bank of the SWIR were observed with petrography to find these dikelets and identify what type of dikelet is present. SEM-EDS is used to identify the mineral assemblages present in the dikelets. LA-ICP-MS is used on amphibole to determine if its …


Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre 2024 Utah State University

Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre

All Graduate Reports and Creative Projects, Fall 2023 to Present

Differing crystallinities of carbonaceous material are common in fault rocks across a range of geologic settings and spatial scales and may provide constraints on strain rate, the nature of fault slip, fluid-rock interactions, and temperature variations over the earthquake cycle. The Pioneer fault at Little Fall Creek in south-central Idaho provides an excellent opportunity to study nanostructure changes of carbonaceous matter as a function of fault deformation. At this location, the Pioneer Fault exhibits a well-defined principal slip zone (PSZ) composed of multi-layered white siliceous mineralization and black carbon to graphite with a continuously exposed adjacent damage zone that includes …


Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo 2024 Portland State University

Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo

Geology Faculty Publications and Presentations

Volcanic glass has been used extensively as a paleoaltimeter. Deuterium (2H) concentrations in glass have been found to be stable over geologic timescales, making δ2H (also known as δD) a reliable proxy for ancient water chemistry. However, continued work revolves around better understanding how different factors affect preserved water in volcanic ash. Here, we analyze δD in the Rattlesnake Tuff (RST), a widespread ca. 7 Ma ash-flow tuff, and create a paleoisoscape to assess variations in δD across Oregon during that time. To this end, 16 ash samples were collected across central and eastern Oregon from …


Public Horticulture: Process And Design Of The Lincoln Botanical Garden, Brad Kindler 2024 University of Nebraska-Lincoln

Public Horticulture: Process And Design Of The Lincoln Botanical Garden, Brad Kindler

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Beginning in 2012, the local non-profit, The Lincoln Botanical Garden, began organizing the conceptual design and creation of a glass conservatory within a botanical garden in Lincoln, Nebraska. These proposed urban enhancements seek to fill a gap in garden amenities in the city by providing year-round access to public horticulture programming and education.

This project, Public Horticulture: Process and Design of the Lincoln Botanical Garden, documents these efforts and makes design recommendations for a themed Glacial Erratic Garden that could be constructed within the botanical garden.

Advisors: Ellen Paparozzi and Sam Wortman


Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham 2024 University of Texas at El Paso

Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham

Open Access Theses & Dissertations

The landscape of central Texas is shaped by over one billion years of Earth's history. An array of lithology lies within central Texas along with two large geological structures. The Llano Uplift, characterized by Proterozoic metamorphic and igneous rocks dating back to 1.37 billion years ago, is encircled by Paleozoic and Mesozoic sedimentary rocks. To the southeast of the Llano Uplift lies the Balcones Fault Zone (BFZ), an extensional structural system of mostly normal faults that delineates the transition between Paleozoic-Mesozoic sedimentary rocks and Cenozoic sedimentary cover, which are influential to the regional hydrogeology. This study investigates the hydrogeological dynamics …


Mauvais Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood, Christopher Spence, Diane F. Van Hoy 2024 University of North Dakota

Mauvais Coulee Hydrologic Simulation Data, Sharhad Wainty, Taufique H. Mahmood, Christopher Spence, Diane F. Van Hoy

Datasets

The authors compiled a hydrologic model for the Mauvais Coulee Basin using Cold Region Hydrologic Platform. The datasets include observed and simulated streamflow, observed climatic data, land use maps and hydrological representative unit maps (HRU) maps. This study detected a mechanism of hydrologic change to wetting using a cold region hydrologic model during 1990-2004 period.


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