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Morphology And Morphometry Of Double Layered Ejecta Craters On Mars, Ryan Schwegman 2015 The University of Western Ontario

Morphology And Morphometry Of Double Layered Ejecta Craters On Mars, Ryan Schwegman

Electronic Thesis and Dissertation Repository

Double layered ejecta (DLE) craters display two distinct layers of ejecta that appear to have been emplaced as a mobile, ground-hugging flow. While volatile content within the target, atmosphere, or some combination of the two is generally considered a major variable enhancing the mobility of ejecta, the presence of unconsolidated surface materials may also have some effect. This statement is studied further here, aiming to determine whether bulk target lithology and/or attributes of the surface have any effect on morphometric properties between DLEs situated on sedimentary targets to those on volcanic ones. Results suggest that ejecta mobility (the distance ...


High Resolution Stratigraphy And Paleoenvironmental Reconstruction Of The Upper Devonian Kettle Point Formation, Southwestern Ontario, Canada, Nikole E. Bingham-Koslowski 2015 The University of Western Ontario

High Resolution Stratigraphy And Paleoenvironmental Reconstruction Of The Upper Devonian Kettle Point Formation, Southwestern Ontario, Canada, Nikole E. Bingham-Koslowski

Electronic Thesis and Dissertation Repository

The Upper Devonian Kettle Point Formation of southwestern Ontario consists of interbedded organic-rich black shales and organic-poor greyish green mudstones and red beds, the distribution of which were controlled by water depth, primary productivity, paleoclimate, and tectonism associated with the concurrent Acadian orogeny. Black shales were deposited under anoxic conditions and represent the background deposition. Less abundant organic-poor lithologies were formed under dysoxic to oxic conditions caused by a drop in relative sea level (either eustatic or related to subsidence or uplift). Sulphur isotope data shows a largely consistent background value for the black shales around -20‰ δ34S ...


Ecology And Morphology Of The Late Miocene Musk Deer, Longirostromeryx Wellsi (Artiodactyla: Moschidae: Blastomerycinae), Katheryn Y. C. Chen 2015 University of Nebraska-Lincoln

Ecology And Morphology Of The Late Miocene Musk Deer, Longirostromeryx Wellsi (Artiodactyla: Moschidae: Blastomerycinae), Katheryn Y. C. Chen

Dissertations & Theses in Earth and Atmospheric Sciences

Longirostromeryx wellsi, one of the latest surviving members of the extinct clade Blastomerycinae (Artiodactyla: Moschidae), possesses highly derived craniodental morphology that deviates from typical musk deer form. Previous work suggests that the unique anatomy of L. wellsi represents adaptations for occupying open savannas. To test this hypothesis I conduct principal components analysis on five postcranial bones of L. wellsi, comparing them to that of several extant ruminant artiodactyls, which are divided among seven habitat categories. These elements are also compared with the postcrania of other blastomerycines. These analyses indicate that L. wellsi anatomy is most similar to that of other ...


Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman 2015 Truman State University

Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman

STAR (STEM Teacher and Researcher) Program Posters

NASA Web World Wind (Web WW) is designed to visualize and manage geographical data. As a first implementation of visualization and analysis, we designed an application to map earthquake data onto the globe. Portions of this code were merged with application monitoring magnetic field anomalies possibly associated with earthquake precursor activity. Web WW enabled the visualization of the directional vectors from this data to point to the source location of the earthquake. We also developed a prototype urban management application which utilizes OpenStreetMaps to provide simple features such as route navigation, geographical and services information in an area of interest ...


Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman 2015 California Polytechnic State University

Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman

STAR (STEM Teacher and Researcher) Program Posters

The primary purpose of this study is to better understand how climate affects river dynamics. It is also important to understand the relationship between glaciers and the transportation of sediments, as this allows us to study changes in transport through time. The studied sediments were gathered from outcrops located in Fresno Ca, off of Friant road. The origin of these sediments are the Sierra Nevada Mountains. Mesozoic metasedimentary and metavolcanic sediments are derived from the foothills, while the granitic sediments are derived from higher up in the mountains. The sediments are characterized by both their degree of rounding, and their ...


The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn 2015 Utah State University

The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn

All Graduate Theses and Dissertations

This dissertation encompasses two studies: one developing virtual field trips for mobile devices for an innovative approach to lower-division geoscience education, and the other examining the role of rock strength in river erosion and landscape evolution.

The education study involves the development of three virtual field trip modules (Geologic Time, Geologic Structures, and Hydrologic Processes, all free on iTunes and Google Play) that lead students down a virtual Colorado River through Grand Canyon by physically moving around their campus quad, football field or other location, using their GPS-equipped smart phone or tablet. As students reach each location in the scaled ...


Strength Study Of Zircon Under High Pressure, Ievgeniia Morozova 2015 The University of Western Ontario

Strength Study Of Zircon Under High Pressure, Ievgeniia Morozova

University of Western Ontario - Electronic Thesis and Dissertation Repository

Zircon (ZrSiO4) is a strong accessory mineral that can retain U, Th and Hf within its structure. This makes zircon an important material in geochemical and geochronological studies. In addition, the strong thermal shock resistance of zircon allows for dating the formations of melt and impact events and to separate shocked and potentially shocked country rocks. However, the deformation mechanism and microstructure behavior of zircon at high pressure is poorly understood. Therefore, this work aims to study the deformation and texture of zircon in situ at high pressure and room temperature, and also to examine the microstructure of samples ...


Quantitative Hermeneutics: Counting Forestructures On A Path From W.M. Davis To The Concept Of Multiple-Permeability Karst Aquifers, H. L Vacher, Lee J. Florea 2015 University of South Florida

Quantitative Hermeneutics: Counting Forestructures On A Path From W.M. Davis To The Concept Of Multiple-Permeability Karst Aquifers, H. L Vacher, Lee J. Florea

International Journal of Speleology

Hermeneutics is the theory of interpretation. One of its major components is recognizing prejudgments, or forestructures, that we bring to our objects of study. In this paper, we construct a historical narrative of the evolution of thinking about the role of caves in relation to groundwater flow in limestone, and we tabulate forestructures as they appear in the story. This account consists of three overlapping time periods: the before and after of an incident that repelled hydrogeologists and students of karst from each other in the middle of the 20th century; a period, up to around the turn of ...


Preliminary Geophysical Characterization Of The Karst Within A Transverse Glade In The Atlantic Coastal Ridge, Miami-Dade County Florida, Usa, Lee J. Florea, Jeff Ransom, Dallas Hazelton 2015 Ball State University

Preliminary Geophysical Characterization Of The Karst Within A Transverse Glade In The Atlantic Coastal Ridge, Miami-Dade County Florida, Usa, Lee J. Florea, Jeff Ransom, Dallas Hazelton

Lee J Florea, PhD, P.G.

In this paper we present results of two DC Electrical Resistivity Tomography surveys at Deering Estate at Cutler in the Atlantic Coastal Ridge of Miami-Dade County, Florida. This County Natural Area encompasses Deering Glade and hosts one of the largest remaining tropical hardwood-hammock ecosystems in the USA. A canal extension, wetland restoration, and pump station recently constructed at Deering Estate by the South Florida Water Management District is designed to re-hydrate Deering Glade to pre-development conditions thus helping to sustain the hammock ecosystem and reverse trends in salt-water intrusion in this portion of the Biscayne aquifer.

For these transects, we ...


Anomalous Thermal Indicators From Authigenic Minerals In Upper Paleozoic Strata Of The Michigan Basin, Kyle Cox 2015 Western Michigan University

Anomalous Thermal Indicators From Authigenic Minerals In Upper Paleozoic Strata Of The Michigan Basin, Kyle Cox

Master's Theses

Indications of anomalous paleo-temperatures exist in strata of the Michigan basin, USA. The thermal history of the basin was investigated through identification and analysis of authigenic components in two Upper Paleozoic strata, the Devonian Dundee Formation and Mississippian Marshall Sandstone. Formation conditions for diagenetic phases in both units were estimated through a variety of means and compared to conditions expected for a simple burial model. Authigenic clays identified in the Marshall via X-ray diffraction are expected to have formed at temperatures above what would have been produced by burial alone. Stable isotope and fluid inclusion analysis indicate the same for ...


Lithologic Properties Of The Upper Ordovician Utica Formation, Michigan Basin, Usa: A Geological Characterization And Assessment Of Carbon Dioxide Confinement Potential, Frank Richard Sattler 2015 Western Michigan University

Lithologic Properties Of The Upper Ordovician Utica Formation, Michigan Basin, Usa: A Geological Characterization And Assessment Of Carbon Dioxide Confinement Potential, Frank Richard Sattler

Master's Theses

The Utica/Maquoketa Shale is considered to be the primary confining layer for Cambro-Ordovician CO2 sequestration targets in the Midwest in the Michigan and Illinois basins, respectively. Prospective regional geologic seals in mudrock formations possess a combination of lithologic properties including nanometer scale pore space, elevated breakthrough pressures for non-wetting fluid phases and ductile mechanical deformation. Mineralogical composition is related to and typically controls these properties.

The objective of this study is to investigate the geological controls on stratigraphic and lithologic variability in the Utica/Collingwood in the Michigan basin. Twelve conventional cores and hundreds of modern well logs ...


Using Declassified Satellite Imagery To Quantify Geomorphic Change: A New Approach And Application To Himalayan Glaciers, Joshua Michael Maurer 2015 Brigham Young University - Provo

Using Declassified Satellite Imagery To Quantify Geomorphic Change: A New Approach And Application To Himalayan Glaciers, Joshua Michael Maurer

All Theses and Dissertations

Himalayan glaciers are key components of earth's cryosphere, acting as hydrological reservoirs vital to many human and natural systems. Most Himalayan glaciers are shrinking in response to changing climate, which will potentially impact water resources, natural hazards, sea level rise, and many other aspects. However, there is much uncertainty regarding the state of these glaciers, as direct field data are difficult to obtain. Accordingly, long-timespan remote sensing techniques are needed to measure changing glaciers, which have memory and often respond to climate on decadal timescales. This study uses declassified historical imagery from the Hexagon spy satellite database to fulfill ...


Analysis And Comparison Of Physical Properties And Morphology Of Impact Melt Flows On Venus And The Moon To Determine Atmospheric Controls, Christine Elizabeth Dong 2015 Bates College

Analysis And Comparison Of Physical Properties And Morphology Of Impact Melt Flows On Venus And The Moon To Determine Atmospheric Controls, Christine Elizabeth Dong

Geology Theses

Impact melt flows form when target material melted by an impact breaches the rim of the impact crater. The melt flows out and away from the crater, forming a lava flow. Such flows have been identified on Venus and the Moon by previous studies. This study aims to document impact melt flows on these two bodies to determine the differences, if any, between them, and to ascertain whether these differences are due to atmospheric conditions. Previously recorded morphological data from Robert Herrick of the Lunar and Planetary Institute and Neish et al. (2014) are used in conjunction with S-band (12 ...


Deformation Post-Doming: New Mapping Of The Oliverian Jefferson Dome, Mt. Dartmouth 7.5' Quadrangle, New Hampshire, Michelle Devoe 2015 Bates College

Deformation Post-Doming: New Mapping Of The Oliverian Jefferson Dome, Mt. Dartmouth 7.5' Quadrangle, New Hampshire, Michelle Devoe

Honors Theses

The Mt. Dartmouth 7.5’ Quadrangle, west of the Presidential Range, contains the southeastern portion of the Jefferson Dome, the largest of the Oliverian Domes. As part of a USGS NHGS EdMap StateMap project, the purpose of this study was to remap this part of the Jefferson Dome and perform a structural and mineralogical analysis of its rock units to develop a better understanding of the tectonic history of the Northeast. Structural analyses show dextral shear zones and folded foliation which suggest at least three phases of deformation post-doming. Literature claims shear zones exist throughout the Northeast, and this analysis ...


Petrogenesis And Paleostress Analysis Of The Mesozoic Mill Brook Dike Zone In The Mount Dartmouth 7.5' Quadrangle, New Hampshire, Graham Grear Oxman 2015 Bates College

Petrogenesis And Paleostress Analysis Of The Mesozoic Mill Brook Dike Zone In The Mount Dartmouth 7.5' Quadrangle, New Hampshire, Graham Grear Oxman

Honors Theses

Field mapping linked with petrogenetic and brittle structural studies of Mesozoic basalt dikes was performed in the Mount Dartmouth 7.5' Quadrangle, adjacent to the Presidential Range, NH. This was done in hopes of creating a better understanding of the intrusion setting and brittle deformational history of the basalt dikes, particularly in relation to the regional tectonic context. Field work done during the summer of 2014 revealed a 100 meter wide, 7.8 km long zone containing multiple mafic dikes that are exceptionally well exposed at the junction of NH Rt. 115 and the Cherry Mountain road. The largest dike ...


Nanodiamond Extraction At A Potential Impact Location, Joel Kathan 2015 DePaul University

Nanodiamond Extraction At A Potential Impact Location, Joel Kathan

DePaul Discoveries

Meteoritic or cometary impacts create the temperature and pressure conditions necessary to form nanodiamonds (NDs). The presence of extracted NDs from rocks of the time and locations of extinctions, fires, or known environmental changes are commonly used to confirm that a theorized cosmic impact occurred to trigger those events. Samples were obtained from an archeological site described in the Old Testament of the Bible as having been destroyed by the God of the Old Testament. To see if the historical description of Biblical events might have been triggered by a cometary impact or explosion, an attempt was made to isolate ...


Insights Into The Evolution Of The Great Plains Grassland Ecosystem Over The Last 5 Million Years From Paleotemperature And Paleovegetation Records, Anne Fetrow 2015 University of Puget Sound

Insights Into The Evolution Of The Great Plains Grassland Ecosystem Over The Last 5 Million Years From Paleotemperature And Paleovegetation Records, Anne Fetrow

Honors Program Theses

Over the last 10 million years, the Great Plains transitioned to the modern C4 grass dominated ecosystem. Well-preserved late Miocene to Holocene fossils and paleosols make the Meade Basin in southwest Kansas, USA a unique place to determine how paleoenvironmental conditions changed during C4 grassland evolution. δ18O values of paleosol carbonates (δ18Ocarb) in the Meade Basin decreased from the Miocene to Holocene while δ13C values increased; these trends were interpreted as an increase in temperature and/or in aridity coincident with an increase of C4 grass biomass on the landscape ...


Geothermobarometry And Petrographic Interpretations Of Christensen Ranch Meta- Banded Iron Formation From The Ruby Range, Montana, Jacob Hughes 2015 Western Kentucky University

Geothermobarometry And Petrographic Interpretations Of Christensen Ranch Meta- Banded Iron Formation From The Ruby Range, Montana, Jacob Hughes

Honors College Capstone Experience/Thesis Projects

The Ruby Range in southwestern Montana was tectonically uplifted during the mountain-building event of the Big Sky orogeny. Contained within the Christensen Ranch Formation, made up of sedimentary units metamorphosed during the Big Sky orogeny, are a small number of metamorphosed banded iron formations (BIFs). It is the presence and composition of these BIFs which is the focus of this research, principally their depositional origin, relationship to surrounding sedimentary packages, elemental and mineral compositions, and lastly, peak metamorphic conditions. Samples were collected, cut into thin sections, and powdered for textural and compositional analyses employing polarized light microscopy, Raman microscopy, scanning ...


Paleoenvironmental Reconstruction Of An Upper Ordovician Rocky Shoreline: The Lindsay Formation Of Heywood And Partridge Islands, Ontario, Hiba-tul Naseer Maheen 2015 The University of Western Ontario

Paleoenvironmental Reconstruction Of An Upper Ordovician Rocky Shoreline: The Lindsay Formation Of Heywood And Partridge Islands, Ontario, Hiba-Tul Naseer Maheen

University of Western Ontario - Electronic Thesis and Dissertation Repository

The islands of Heywood and Partridge, located northeast of Manitoulin Island in Georgian Bay, Ontario, preserve a major unconformity between the Paleoproterozoic Bar River and Lorrain Formation quartz arenite and Upper Ordovician Lindsay Formation carbonate and mudrock. The Lindsay Formation strata record two transgressive pulses of an epeiric sea that flooded the North American continent during the Late Ordovician. During this time, mountain building processes associated with the Taconic Orogeny were taking place to the present east, and the tectonic effects of this orogeny resulted in subsidence of the Michigan Basin. The Lindsay Formation of the Trenton Group was deposited ...


Nwa 8614: The Least Heated Winonaite, Karla Farley, Alex Ruzicka, Katherine Armstrong 2015 Portland State University

Nwa 8614: The Least Heated Winonaite, Karla Farley, Alex Ruzicka, Katherine Armstrong

Student Research Symposium

Northwest Africa 8614 is classified as a winonaite on the basis of oxygen isotope ratios, mineralogy, and highly reduced chemistry. Unlike other winonaites, it contains numerous and readily apparent chondrules. Here we discuss various features of NWA 8614 and the possible significance of the meteorite.

Petrological and chemical analyses were performed using optical microscopy with a DM2500 Leica petrographic microscope and a Zeiss Sigma VP-FEG scanning electron microscope (SEM) with a high-efficiency energy dispersive spectrometer (EDS). Oxygen isotopes were analyzed by Karen Ziegler at the University of New Mexico on acid-washed samples to remove terrestrial weathering products.

Owing to the ...


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