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Detrital Zircon Analysis Of The Taza-Guercif Basin And The Adjacent Rif And Middle Atlas Mountains Of Morocco And X-Ray Fluorescence Chemofacies Analysis Of The Maness Shale Of East Texas, Jonathan Richard Pratt 2015 University of South Carolina - Columbia

Detrital Zircon Analysis Of The Taza-Guercif Basin And The Adjacent Rif And Middle Atlas Mountains Of Morocco And X-Ray Fluorescence Chemofacies Analysis Of The Maness Shale Of East Texas, Jonathan Richard Pratt

Theses and Dissertations

The research in this compilation encompasses three studies leveraging quantitative chemical analyses to interpret the sedimentary record to reconstruct geologic history. The first study surveys the detrital zircon U-Pb and zircon fission-track geochronology of the sedimentary Cretaceous Ketama and Tisiren units of the Rif Mountains, and the Bou Rached sandstones of the Middle Atlas Mountains. All analyzed samples contain a population of Mesoproterozoic crystallization ages formerly unknown to northwest Africa. Possible sources for these ages include the Avalonian terranes now present on the northeastern seaboard of North America, and/or zircons derived from the Amazonian craton and preserved in the Pan-African …


Water Quality, Chemistry, And Hydrology Of Salt Creek In Northeastern Illinois, Luke Lampo 2015 Augustana College - Rock Island

Water Quality, Chemistry, And Hydrology Of Salt Creek In Northeastern Illinois, Luke Lampo

Celebration of Learning

Salt Creek flows through the metropolitan area of Chicago and into the Des Plaines River. Its urban environment provides multiple sources of contamination, including storm runoff, combined sewer overflow, and wastewater treatment plant discharge. The purpose of this study is to determine how water chemistry changes downstream, whether the presence and levels of metals meet IPCB (Illinois Pollution Control Board) and EPA (Environmental Protection Agency) water quality standards, and how water chemistry changes during periods of storm flow and base flow. The study area consists of 10 sites along a 37 km stretch of Salt Creek. Water samples were taken …


Geochemical Analysis Of Surface Materials Surrounding The Bautsch-Gray Mine Superfund Site Near Galena, Illinois, Ryan Plath 2015 Augustana College - Rock Island

Geochemical Analysis Of Surface Materials Surrounding The Bautsch-Gray Mine Superfund Site Near Galena, Illinois, Ryan Plath

Celebration of Learning

The Bautsch-Gray zinc and lead mine, near Galena, Ill., was in operation from the early 1900s until closing in 1975. The mine’s tailings pile has documented elevated lead and zinc concentrations in the surface materials surrounding the site. Numerous floods have caused contaminated sediment to migrate off the mine tailings pile, across Blackjack Road and into an outwash basin, and towards Smallpox Creek. Since this site was designated an EPA priority list superfund site in 2010, there have been numerous remediation efforts.

This study attempts to develop a better understanding of the contamination within the soils of the outwash basin …


Aerosol Size Distribution Measurements During The 2014 Nasa Sarp Campaign In The Central Valley And Sierra Nevada Mountains In California, Victoria A. Hampton 2015 Western Kentucky University

Aerosol Size Distribution Measurements During The 2014 Nasa Sarp Campaign In The Central Valley And Sierra Nevada Mountains In California, Victoria A. Hampton

Mahurin Honors College Capstone Experience/Thesis Projects

Aerosols are directly and indirectly related to global climate by scattering radiation and also by seeding cloud formation. As a part of the 2014 NASA Student Airborne Research Program (SARP), research flights were conducted over the Central California region to better understand air quality in large urban California cities and also in the Central Valley. Using a Droplet Measurement Technologies Ultra High Sensitivity Aerosol Spectrometer (DMT-UHSAS), aerosol size distributions were measured across geographic regions of interest. Previous research has suggested that aerosols originating in the Central Valley may travel eastward to the Sierra Nevada and, once lifted orographically, could suppress …


The Effect Of Substrate On Quartz Precipitation Rates, Victoria Igoe 2015 Bowling Green State University

The Effect Of Substrate On Quartz Precipitation Rates, Victoria Igoe

Honors Projects

The role of substrate on the precipitation of quartz from solution is a confused subject based on past research. The two types of surfaces examined in this project, weathered surfaces and freshly fractured surfaces, may or may not influence the rate of precipitation of quartz from aqueous solution. Precipitation rates on these surfaces are compared via 'sandwich' type experiments, where both naturally weathered quartz grains and freshly fractured synthetic quartz grains are placed in weld-sealed gold tubes, separated by a cement source of amorphous silica. The experiments were run at 450 degrees Celsius and about 150 MPa for varying amounts …


Inferring The Oriented Elastic Tensor From Surface Wave Observations: Preliminary Application Across The Western United States, Jiayi Xie, Michael H. Ritzwoller, S. J. Brownlee, B. R. Hacker 2015 University of Colorado Boulder

Inferring The Oriented Elastic Tensor From Surface Wave Observations: Preliminary Application Across The Western United States, Jiayi Xie, Michael H. Ritzwoller, S. J. Brownlee, B. R. Hacker

Environmental Science and Geology Faculty Research Publications

Radial and azimuthal anisotropy in seismic wave speeds have long been observed using surface waves and are believed to be controlled by deformation within the Earth’s crust and uppermost mantle. Although radial and azimuthal anisotropy reflect important aspects of anisotropic media, few studies have tried to interpret them jointly. We describe a method of inversion that interprets simultaneous observations of radial and azimuthal anisotropy under the assumption of a hexagonally symmetric elastic tensor with a tilted symmetry axis defined by dip and strike angles. We show that observations of radial anisotropy and the 2ψ component of azimuthal anisotropy for Rayleigh …


Geochemical Analysis Of Surface Materials Surrounding The Bautsch-Gray Mine Superfund Site Near Galena, Illinois, Ryan Plath 2015 Augustana College

Geochemical Analysis Of Surface Materials Surrounding The Bautsch-Gray Mine Superfund Site Near Galena, Illinois, Ryan Plath

Geology: Student Scholarship & Creative Works

The Bautsch-Gray zinc and lead mine, near Galena, IL, was in operation from the early 1900s until closing in 1975. The mine’s tailings pile has documented elevated lead and zinc concentrations in the surface materials surrounding the site. Numerous floods have caused contaminated sediment to migrate off the mine tailings pile, across Blackjack Road and into an outwash basin, and towards Smallpox Creek. Since this site was designated an EPA priority list Superfund site in 2010, the EPA has conducted numerous remediation efforts. This study attempts to develop a better understanding of the contamination within the soils of the outwash …


Geochemical Characterization Of The Mountain Home Geothermal System, Trevor Alex Atkinson 2015 Utah State University

Geochemical Characterization Of The Mountain Home Geothermal System, Trevor Alex Atkinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Mountain Home (MH) geothermal system of the western Snake River Plain (SRP) magmatic province was discovered in 2012 by the Snake River Geothermal Drilling Project. Artesian flowing water with a temperature of 150°C was encountered at a depth of 1745 m below ground surface (mbgs) and extensive mineralized fracture networks of pectolite-prehnite, calcite, and laumontite were discovered in the recovered core. The objectives of this study are to: 1) describe the thermal and compositional history of past geothermal fluids, and 2) compare these fluids to modern fluids in order to characterize the evolution of the MH geothermal system and …


On The Temporal Evolution Of Long-Wavelength Mantle Structure Of The Earth Since The Early Paleozoic, Shijie Zhong, Maxwell L. Rudolph 2015 University of Colorado Boulder

On The Temporal Evolution Of Long-Wavelength Mantle Structure Of The Earth Since The Early Paleozoic, Shijie Zhong, Maxwell L. Rudolph

Geology Faculty Publications and Presentations

The seismic structure of the Earth’s lower mantle is characterized by a dominantly degree-2 pattern with the African and Pacific large low shear velocity provinces (i.e., LLSVP) that are separated by circum-Pacific seismically fast anomalies. It is important to understand the origin of such a degree-2 mantle structure and its temporal evolution. In this study, we investigated the effects of plate motion history and mantle viscosity on the temporal evolution of the lower mantle structure since the early Paleozoic by formulating 3-D spherical shell models of thermochemical convection. For convection models with realistic mantle viscosity and no initial structure, it …


Unraveling Controls On Fracture Stratigraphy In Carbonates: The Influence Of Regional Stress, Mechanical Properties, And Diagenesis, Matthew H. Peppers 2015 University of Nebraska-Lincoln

Unraveling Controls On Fracture Stratigraphy In Carbonates: The Influence Of Regional Stress, Mechanical Properties, And Diagenesis, Matthew H. Peppers

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Fracture characteristics analyzed from outcrops provide key insights into the migration pathways of subsurface hydrocarbons, and allow for a detailed understanding of the tectonic history in an area. This study looks to assess the impacts that various controlling factors have on the development of fracture characteristics. To complete this objective, a succession of Ordovician to Mississippian rocks was examined. The logged section includes the Cotter Dolomite, Chattanooga Shale, St. Joe Formation, and the Boone Formation (subdivided into informal Upper and Lower members). Located in northwestern Arkansas and southwestern Missouri, data were collected from roadcut exposures along Highway 71. Collected fracture …


Stratigraphy And Depositional Environment Of The Mesaverde Group In The Northern Bighorn Basin Of Wyoming, Gordon Adams 2015 University of Nebraska-Lincoln

Stratigraphy And Depositional Environment Of The Mesaverde Group In The Northern Bighorn Basin Of Wyoming, Gordon Adams

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A sedimentological, stratigraphical and palynological study was conducted on the upper Cretaceous (Campanian) Mesaverde Group over 27.5 km of a north-south-orientated outcrop belt in the northern Bighorn Basin, Wyoming. During the Campanian, the study area lay in the western part of the Cretaceous Western Interior Seaway. The study aims to provide a stratigraphic and paleoenvironmental analysis of the Mesaverde Group and to integrate findings with data from outcrop belts to the south (southern Bighorn Basin), north (Montana) and east (Powder River Basin).

The Mesaverde Group (371 - 515 m thick) comprises a succession of mainly coarsening-upward stratal cycles, with some …


Carbon Isotope Variations Associated With A Middle Ordovician Karstic Unconformity, Patricia Suzanne Williams 2015 University of Nevada, Las Vegas

Carbon Isotope Variations Associated With A Middle Ordovician Karstic Unconformity, Patricia Suzanne Williams

UNLV Theses, Dissertations, Professional Papers, and Capstones

Large negative carbon isotope (δ13C) excursions have been documented from late Neoproterozoic-Paleozoic successions. These δ13C excursions have been widely used for regional and global stratigraphic correlation, particularly in strata with limited paleontological and radiometric age controls. Recent studies, however, argued that some negative δ13C excursions from stratigraphic record may have been resulted from meteoric/burial diagenesis, which commonly shifts both carbon and oxygen isotopes toward lower values. Testing the diagenetic origin of δ13C excursions in stratigraphic successions without independent stratigraphic framework has been difficult because it evolves into circular arguments about stratigraphic completeness …


Going With The Flow Or Against The Grain? The Promise Of Vegetation For Protecting Beaches, Dunes, And Barrier Islands From Erosion, Rusty A. Feagin, Jens Figlus, Julie C. Zinnert, Jake Sigren, Marisa L. Martínez, Rodolfo Silva, William K. Smith, Ashley Cox, Daniel Cox, Donald R. Young, Gregory A. Carter 2015 Texas A & M University - College Station

Going With The Flow Or Against The Grain? The Promise Of Vegetation For Protecting Beaches, Dunes, And Barrier Islands From Erosion, Rusty A. Feagin, Jens Figlus, Julie C. Zinnert, Jake Sigren, Marisa L. Martínez, Rodolfo Silva, William K. Smith, Ashley Cox, Daniel Cox, Donald R. Young, Gregory A. Carter

Faculty Publications

Coastlines have traditionally been engineered to maintain structural stability and to protect property from storm‐related damage, but their ability to endure will be challenged over the next century. The use of vegetation to reduce erosion on ocean‐facing mainland and barrier island shorelines – including the sand dunes and beaches on these islands – could be part of a more flexible strategy. Although there is growing enthusiasm for using vegetation for this purpose, empirical data supporting this approach are lacking. Here, we identify the potential roles of vegetation in coastal protection, including the capture of sediment, ecological succession, and the building …


Comparing Slug Test Methods For Unconfined Aquifers, Hussain Jaber Alfaifi 2015 Western Michigan University

Comparing Slug Test Methods For Unconfined Aquifers, Hussain Jaber Alfaifi

Dissertations

Slug test methods are used to determine in situ aquifer hydraulic conductivity (K) more quickly and economically than a pump test can. This study compares slug test methods for unconfined aquifers, looking at how to conduct a test using a physical slug, and at different analysis methods including Bouwer and Rice (1976), Kansas Geological Survey (KGS 1994), Hvorslev (1951) and Dagan (1978). Questions that motivated this study include: How well does the Bouwer and Rice method work? What is the most effective way to conduct a slug test? Does using a large physical slug relative to the well diameter and …


A Comparative Study To Calculate Hydraulic Conductivity In Ultisols On An East Tennessee Hillslope, Sydney A. Lawson 2015 East Tennessee State University

A Comparative Study To Calculate Hydraulic Conductivity In Ultisols On An East Tennessee Hillslope, Sydney A. Lawson

Undergraduate Honors Theses

This study compares four different methods to measure hydraulic conductivity (K) at two sites on the East Tennessee State University Valleybrook Campus. It compares the K values to each other, to the different K values between the two sites, and to United States Department of Agriculture (USDA) K values. Two field methods, Well Bail Test and Auger Hole Test, and two lab methods, Constant Head Permeameter Test and Grain Size Distribution Test (GSD), were performed on the clay rich Ultisol soils on an East Tennessee hillslope in the Valley and Ridge Physiographic Province. One site was located close to a …


Using Geometric Morphometrics To Differentiate Lower First Molars Of Microtus Species: A Review Of The Clark’S Cave Bone Deposit, Va, Mark Shelleman 2015 East Tennessee State University

Using Geometric Morphometrics To Differentiate Lower First Molars Of Microtus Species: A Review Of The Clark’S Cave Bone Deposit, Va, Mark Shelleman

Electronic Theses and Dissertations

Clark’s Cave contains a large collection of late Pleistocene mammal material. In particular, it contains a sizable amount of Microtus spp. which can be valuable paleoclimate indicators. Identification techniques traditionally used to classify these species have been shown to be unreliable. Recent studies have shown that using geometric morphometric techniques on lower first molars can be more successful. By placing landmarks and running a discriminate analysis on new and previously collected material from the cave, significant differences in Microtus species proportions were found. Specifically, showing the deposit has a larger proportion of M. xanthognathus than previously reported; resulting in a …


Using Kriging, Cokriging, And Gis To Visualize Fe And Mn In Groundwater, Crystal Johnson 2015 East Tennessee State University

Using Kriging, Cokriging, And Gis To Visualize Fe And Mn In Groundwater, Crystal Johnson

Electronic Theses and Dissertations

For aesthetic, economic, and health-related reasons, allowable concentrations of iron (Fe) and manganese (Mn) found present in drinking water are 0.3 mg/L and 0.05 mg/L, respectively. Water samples taken from private drinking wells in the rural communities within Buncombe County, North Carolina contain amounts of these metals in concentrations higher than the suggested limits. This study focused on bedrock geology, elevation, saprolite thickness, and well depth to determine factors affecting Fe and Mn. Using ArcGIS 10.2, spatial trends in Fe and Mn concentrations ranges were visualized, and estimates of the metal concentrations were interpolated to unmonitored areas. Results from this …


Determining Crustal Structure Beneath Seismic Stations Overlying A Low-Velocity Sedimentary Layer Using Receiver Functions, Youqiang Yu, Jianguo Song, Kelly H. Liu, Stephen S. Gao 2015 Missouri University of Science and Technology

Determining Crustal Structure Beneath Seismic Stations Overlying A Low-Velocity Sedimentary Layer Using Receiver Functions, Youqiang Yu, Jianguo Song, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The receiver function (RF) technique has been widely applied to investigate crustal and mantle layered structures using P-to-S converted (Ps) phases from velocity discontinuities. However, the presence of low-velocity (relative to that of the bedrock) sediments can give rise to strong reverberations in the resulting RFs, frequently masking the Ps phases from crustal and mantle boundaries. Such reverberations are caused by P-to-S conversions and their multiples associated with the strong impedance contrast across the bottom of the low-velocity sedimentary layer. Here we propose and test an approach to effectively remove the near-surface reverberations and decipher the Ps phases associated with …


A Chronostratigraphic Record Of Arroyo Entrenchment And Aggradation In Kanab Creek, Southern Utah, Kirk F. Townsend 2015 Utah State University

A Chronostratigraphic Record Of Arroyo Entrenchment And Aggradation In Kanab Creek, Southern Utah, Kirk F. Townsend

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to explore the processes that lead to the formation of arroyos. Arroyos are entrenched stream channels with steep sides that form by incision into valley-fill sediment, and are common features throughout the southwest United States. Many of these systems formed during the late AD 1800s and early 1900s in one of the most significant historic geomorphic events in the region. At this time, former river floodplains were abandoned, creating terraces. This caused a decline in local water tables and associated changes in stream discharge, vegetative communities, and the ability to irrigate once fertile floodplains. …


Sequence Stratigraphy, Depositional Environments And Geochemistry Of The Middle Cambrian Bloomington Formation In Northern Utah, Christopher Ryan Jensen 2015 Utah State University

Sequence Stratigraphy, Depositional Environments And Geochemistry Of The Middle Cambrian Bloomington Formation In Northern Utah, Christopher Ryan Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bloomington Formation (~425 m thick) is a latest Middle Cambrian (~506.5-505 Ma.), mixed warm water, carbonate and shale unit on the Cordilleran passive margin in northern Utah and southern Idaho. The Hodges Shale and Calls Fort Shale Members are shale dominated and the Middle Limestone Member is a thick carbonate. Fossil diversity and abundance is surprisingly low for a Middle Cambrian carbonate/shale formation. Present, however, are 10-50 cm thrombolite mud mounds, associated with Girvanella oncoliths. These mud mounds represent shallow water carbonates that experienced a small flooding event that gives the mud mounds time and proper conditions to build …


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