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An Elemental Highway: Investigation Of A High Nickel Anomaly In Olivine From The Island Of Niihau, Hawaii, Alexander James Valentine 2017 University of Nevada, Las Vegas

An Elemental Highway: Investigation Of A High Nickel Anomaly In Olivine From The Island Of Niihau, Hawaii, Alexander James Valentine

UNLV Theses, Dissertations, Professional Papers, and Capstones

The study of volcanic geochemistry is one of the main gateways for investigating the Earth’s mantle. One important topic in the field is that of nickel (Ni) in the mineral olivine. While Ni is a compatible element in olivine, its high concentration at a given MgO content is not well understood. A variety of hypotheses have been proposed, including attributing presence of Ni to pyroxenite source melting, contribution from the core, or variation in peridotite source melting. In addition to the other hypotheses, chemical diffusion may also be a mechanism for enriching olivine Ni concentration. Magnesium-iron (Mg-Fe) isotopic measurements ...


Late Cretaceous Extensional Collapse Of The Southern Cordillera: Evidence From The Bristol And Granite Mountains, Se California, Lee Hess 2017 University of Nevada, Las Vegas

Late Cretaceous Extensional Collapse Of The Southern Cordillera: Evidence From The Bristol And Granite Mountains, Se California, Lee Hess

UNLV Theses, Dissertations, Professional Papers, and Capstones

Demonstrating the regional extent of Late Cretaceous extensional collapse of western North America’s southern Cordillera is important to understanding the tectonic evolution of the Sevier-Laramide orogens, and the geodynamics of ancient and modern orogens and synconvergent extension. Documenting Late Cretaceous extension in the southern Cordillera requires looking through the extensive overprint by Cenozoic structures. Late Cretaceous extension in the eastern Mojave region has been inferred from geochronology and thermochronology studies, which document Late Cretaceous cooling of Mesozoic granitoid rocks, some of which were emplaced in the middle crust. Cooling histories from these rocks have also been interpreted to be ...


Terroir Studies In Washington And Wisconsin American Viticultural Areas, Snejana Karakis 2017 University of Wisconsin-Milwaukee

Terroir Studies In Washington And Wisconsin American Viticultural Areas, Snejana Karakis

Theses and Dissertations

The concept of terroir has been evaluated since the 12th century, when Cistercian monks from Burgundy realized that the physical environment in which grapes are grown has a major influence on the character and quality of the resulting wine. These environmental conditions affecting grape and wine quality are known as terroir in viticulture and have become increasingly important in the grape growing and wine industry. In this dissertation, three studies investigating the terroir of vineyards located in Washington and Wisconsin American Viticultural Areas (AVAs), which are defined by the Alcohol and Tobacco Tax and Trade Bureau (TTB) as delimited grape-growing ...


Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi 2017 Clark University

Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi

International Development, Community and Environment (IDCE)

This paper is a description of our internship with Clark Labs in the summer of 2016. We worked as research assistants in the Deforestation Risk Prediction project for Ecosystem Services team. This goal of the project was to predict deforestation at global, continental and national level. Our responsibilities were to choose the variables that may influence the deforestation and to use Land Change Modeler in TerrSet to test the variables and create the deforestation prediction maps. We highly recommend this internship with Clark Labs to other GISDE students who are interested in land change analysis.


Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott 2017 Clark University

Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott

International Development, Community and Environment (IDCE)

This project paper details the activities carried out as a Geologist/GIS Specialist in the Gateway National Recreation Area as a part of the Geoscientists-In-The-Park internship program. The focus of this position was on supporting the geomorphological monitoring efforts of the National Park Service. This was accomplished through a combination of field data collection, GIS analysis, report writing, and project work. By the end of the internship, substantial progress was made to the formation of Gateway’s Annual 1D and 2D report for 2015-2016, field data were collected for the 2016 summer season, changes in geomorphology were explored and summarized ...


Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey 2017 University of Arkansas, Fayetteville

Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey

Theses and Dissertations

The dynamics of channel mouth bifurcations on river deltas can be understood using theory developed in tributary channel networks. Bifurcations in groundwater-fed tributary networks have been shown to evolve dependent on diffusive ground water flow patterns

directly adjacent to the channel network, producing a critical angle of 72°. We test the hypothesis that bifurcation angles in distributary channel networks are likewise dictated by a diffusive external flow field, in this case the shallow surface water surrounding the subaqueous portion of distributary channels in a deltaic setting. We measured 25 unique distributary bifurcations in an experimental delta and 197 bifurcations in ...


Lost Names In The Paleozoic Lithostratigraphy Of Arkansas, Noah Morris 2017 University of Arkansas, Fayetteville

Lost Names In The Paleozoic Lithostratigraphy Of Arkansas, Noah Morris

Theses and Dissertations

The geology of Arkansas has been studied for nearly 160 years, and our understanding of it is continually evolving. Part of this ever-changing study is the nomenclature of the stratigraphy. From the early reports to today, several lithostratigraphic names have been proposed and abandoned to improve the accuracy and clarity of the understanding of Arkansas’ geology. Over these 160 years of study, 214 names have been proposed for the Paleozoic beds of Arkansas, with nearly 80 of them currently in use today. These names are a testimony and legacy of the history of Arkansas’ natural resource development and Arkansas’ geologists ...


Using Cross-Sets For Paleodischarge Estimation And Paleocurrent Vectors In The Parthenon Sandstone, Northwest Arkansas, Sean Robert Parry 2017 University of Arkansas, Fayetteville

Using Cross-Sets For Paleodischarge Estimation And Paleocurrent Vectors In The Parthenon Sandstone, Northwest Arkansas, Sean Robert Parry

Theses and Dissertations

In this thesis, set thicknesses are used to estimate the paleohydraulics (paleodischarge and give magnitudes for paleocurrent directions) of the ancient river system which deposited the Parthenon Sandstone in northwest Arkansas. Set thickness is the vertical thickness of a group of strata conformable series (Mckee and Weir, 1953); set thickness represents truncated dunes. The goal of this thesis is to: 1) obtain paleodischarge estimates of the Parthenon sandstone via cross-sets and compare the results with previously calculated discharge estimates which use basin area to discharge collation techniques and 2) use paleodischarge estimates calculated within this thesis to give magnitude to ...


Exploring The Calvert Cliffs: Interpreting Classic Miocene Sequences Through The Application Of Strontium Isotope Stratigraphy And Paleoecology, Joshua B. Zimmt 2017 College of William and Mary

Exploring The Calvert Cliffs: Interpreting Classic Miocene Sequences Through The Application Of Strontium Isotope Stratigraphy And Paleoecology, Joshua B. Zimmt

Undergraduate Honors Theses

The Calvert Cliffs (Maryland, USA) is a classic condensed Miocene sequence that has attracted much scientific attention for its laterally extensive and highly condensed fossil beds (Kidwell, 1982a). Several meters thick and up to 70% shell material, the period of formation of these major complex shell beds has been debated for decades. Kidwell (1989) and associated studies have demonstrated that the major complex shell beds possess certain characteristics that suggest the beds formed as a succession of condensed parasequences during a transgressive systems tract. However, no quantitative analysis has calculated the period of formation of the major complex shell beds ...


The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard 2017 University of Nebraska - Lincoln

The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard

Conservation and Survey Division

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Richardson County that has not been published in readily accessible formats previously. Many of the maps presented herein are based on data from registered well logs and test hole logs that are publicly available on-line, which become more valuable when compiled, analyzed, and discussed as a whole. The focus of the maps presented in this report is the accessibility of groundwater for pumping.


Creating A Scaling Relationship Between Peak Discharge And Drainage Area To Identify Tile Drainage Inputs Into An Agricultural Stream, Ryan Plath 2017 Illinois State University

Creating A Scaling Relationship Between Peak Discharge And Drainage Area To Identify Tile Drainage Inputs Into An Agricultural Stream, Ryan Plath

Theses and Dissertations

Tile drains have been shown to contribute to high levels of nitrate in agricultural streams. Locations of tile drains on a watershed scale, however, are often unknown due to tile drains being located on many separate parcels of private property. This study evaluates the ability of a methodology, using scaling relationships between discharge and drainage area, for locating areas of large tile drainage contribution to Money Creek, in McLean County, Illinois. Additionally, this study examines the difference in scaling relationships and physical stream hydrology between tileflow and no-tileflow conditions. Eight stream sites were created in the watershed, that recorded stage ...


Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. DiBiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth 2017 Pennsylvania State University

Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. Dibiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth

Geology Faculty Publications and Presentations

Existing hillslope sediment transport models developed for low-relief, soil-mantled landscapes are poorly suited to explain the coupling between steep rocky hillslopes and headwater channels. Here we address this knowledge gap using a series of field and numerical experiments to inform a particle-based model of sediment transport by dry ravel—a mechanism of granular transport characteristic of steep hillslopes. We find that particle travel distance increases as a function of the ratio of particle diameter to fine-scale (1m) topographic variability associated with rocky landscapes. Applying a 2-D dry-ravel-routing model to lidar-derived surface topography, we show how spatial patterns of local and ...


Vegetation Habitat Mapping Of Mammoth Cave National Park Using Multi-Date Landsat-8 Imagery And Lidar Data, Hongli Yang 2017 Murray State University

Vegetation Habitat Mapping Of Mammoth Cave National Park Using Multi-Date Landsat-8 Imagery And Lidar Data, Hongli Yang

Steeplechase

Vegetation habitat mapping can be regarded as a model predicting the geographic distribution of plant cover types from mapped environmental variables. This paper discusses three environmental factors- slope, aspect and bedrock geology that determined different habitat types in Mammoth Cave National Park. The variation of aspect and slope can largely determine the amount of solar radiation and water available to vegetation, which influences the contrasting habitat types formed in a long term. Bedrock geology, one of the most influential factor in the study area, primarily controls the soil types and drainage conditions that support the various habitat types. The habitat ...


Karst Sub-Basin Delineation Via Dye Trace Study Near Turnhole Bend, Mammoth Cave National Park, Jake Tholen 2017 Western Michigan University

Karst Sub-Basin Delineation Via Dye Trace Study Near Turnhole Bend, Mammoth Cave National Park, Jake Tholen

Honors Theses

Establishing watershed boundaries is a critical stage in understanding the local water cycle. Drainage basins are typically identified by topographic divides; water flows to successively lower locations along the most direct path available. The karst terrain in Mammoth Cave National Park, however, presents additional challenges in identifying the boundaries of these basins. Underground drainages in the form of caves or conduits often do not correspond with surface topography. These passages can redirect water far from the most immediate surface release.

A dye trace study is designed to identify flow paths from the surface to springs along the Green River. Three ...


Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow 2017 University of new mexico

Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow

Earth and Planetary Sciences ETDs

A dense array of ~1,000 continuously recording, short-period geophones was deployed in the summer of 2014 within ~15 km of Mount St. Helens. Two earthquake catalogs created using reverse time imaging and template detection techniques, increase the detection rate and completeness of the earthquake catalog when compared to the permanent network, Pacific Northwest Seismic Network, catalog. An investigation into event type for ~200 of the earthquake detections leads to the discrimination of two major classification groups, volcano-tectonic and long period. Previous to this study, long period earthquakes had not been identified in the upper crust during a volcanically inactive ...


Petrographic Analysis Of The Oriskany Sandstone (Lower Devonian) From The Ellisburg Storage Pool, Potter County, Northcentral Pennsylvania, Emily R. Jackson 2017 Cedarville University

Petrographic Analysis Of The Oriskany Sandstone (Lower Devonian) From The Ellisburg Storage Pool, Potter County, Northcentral Pennsylvania, Emily R. Jackson

The Research and Scholarship Symposium

Three Lower Devonian Oriskany Sandstone cores, EW-216 (core 1), EW-415 (core 2), and EW-706 (core 3), were obtained from Dominion Transmission’s Ellisburg Storage Pool, located in Potter County, northcentral PA. The goal of the project was to create a petrographic analysis and description of the cores, with special attention given to any deformational features associated with stress/strain indicators. Extended Range Helium Porosimeter measurements, XRD analysis, and thin section production were completed by Calgary Rock and Materials. The cores were then analyzed using a petrographic microscope; a complete description from the analysis was written for each core. Photographs were ...


Genuine Or Reproduction: A Comparision Of 3d Imaging Techniques, Erica A. Loughner, Jordan C. Oldham 2017 Cedarville University

Genuine Or Reproduction: A Comparision Of 3d Imaging Techniques, Erica A. Loughner, Jordan C. Oldham

The Research and Scholarship Symposium

Advancements in technology associated with 3D imaging for both print and digital applications are transforming many aspects of geology. Museums, researchers, and educators are now using 3D models to depict and reproduce fossils, minerals, and crystals for study, thereby reducing the risk of damage to valuable original specimens. This project examined which of the two processes available to Cedarville University geology program produces the best quality digital image and, subsequently, the best 3D printed object of a macroscopic-sized specimen. The first method utilizes the camera on a smartphone to take overlapping photos of the entire specimen (fossil or mineral) – top ...


The Relationship Between Static Water Levels, Bedrock Topography, And Glacial Drift Thickness For The Cedarville, Greene County, Ohio Area, Joel G. Twinem 2017 Cedarville University

The Relationship Between Static Water Levels, Bedrock Topography, And Glacial Drift Thickness For The Cedarville, Greene County, Ohio Area, Joel G. Twinem

The Research and Scholarship Symposium

Cedarville, Ohio, is an area covered in glacial deposits from the Pleistocene age. During this time, the Silurian dolomitic bedrock was exposed and worn down. Glacial till composed of sand and gravel was deposited atop the dolomite in wake of the glaciers retreat. The combination of vuggy bedrock and permeability of the overlying sediments cause the area to be very conducive to aquifer storage and movement. This study attempts to determine the relationship between bedrock topography, till thickness, and static water level, as well as the implications for future drilling. 26 static water levels were measured in the field using ...


Algal Blooms At Lake Erie, Crychelle Portis-Hurlbert 2017 Kent State University

Algal Blooms At Lake Erie, Crychelle Portis-Hurlbert

Student Showcase for Research, Scholarship & Creativity

Harmful algal blooms are a large amount of microscopic photosynthesizing aquatic organisms that produce biotoxins. This type of vibrant green algae contains cyanobacteria and eukaryotic taxa. It also produces a visible algal scum on the surface of the water and causes taste and odor issues in drinking water. Cyanobacteria found in this algae can contribute to human health problems, such as, skin irritations from contact, gastrointestinal, respiratory, and neurological issues. It is also harmful to animals, mainly canines and livestock. The main causes of these algal blooms are fertilizers used in agricultural practices, urban runoff, and improper treatment of wastewater ...


Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard 2017 Stephen F. Austin State University

Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard

International Journal of Speleology

Evaporite karst throughout the Gypsum Plain of west Texas is complex and extensive, including manifestations ranging from intrastratal brecciation and hypogene caves to epigene features and suffosion caves. Recent advances in hydrocarbon exploration and extraction has resulted in increased infrastructure development and utilization in the area; as a result, delineation and characterization of potential karst geohazards throughout the region have become a greater concern. While traditional karst surveys are essential for delineating the subsurface extent and morphology of individual caves for speleogenetic interpretation, these methods tend to underestimate the total extent of karst development and require surficial manifestation of karst ...


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