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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 ...


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 ...


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 ...


A Quarter Century Of Geology At The Gulf Coast Research Laboratory (1948-1973), Ervin G. Otvos Jr. 2015 Gulf Coast Research Laboratory

A Quarter Century Of Geology At The Gulf Coast Research Laboratory (1948-1973), Ervin G. Otvos Jr.

Gulf and Caribbean Research

Overview of the history of geology courses and research at the Gulf Coast Research Laboratory in Ocean Springs, Mississippi.


A Study On Photodegradation And The Fate Of Pyrogenic Carbon, John T. Howell 2015 University of Southern Mississippi

A Study On Photodegradation And The Fate Of Pyrogenic Carbon, John T. Howell

Master's Theses

Accounting for all possible sources of atmospheric CO2 is a pressing issue today due to the increasing effects of climate change. Estimates suggested that on the order of 1.3 million tons of dissolved pyrogenic carbon (pyDOC) could be entering the northern Gulf of Mexico annually. Assessing the fate of pyDOC in aquatic systems is crucial to understanding ecosystem impacts and potential feedback to climate change. Current research indicates that despite a generally lower susceptibility to biodegradation than their unpyrolyzed equivalents, pyrogenic carbon is not environmentally inert. While the role of microorganisms on the fate and transformation ...


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

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 ...


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

Dissertations & Theses in Earth and Atmospheric Sciences

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 ...


Geological Object Recognition In Extraterrestrial Environments, Gregory M. Elfers 2015 The University of Western Ontario

Geological Object Recognition In Extraterrestrial Environments, Gregory M. Elfers

University of Western Ontario - Electronic Thesis and Dissertation Repository

On July 4 1997, the landing of NASA’s Pathnder probe and its rover Sojourner marked the beginning of a new era in space exploration; robots with the ability to move have made up the vanguard of human extraterrestrial exploration ever since. With Sojourners landing, for the rst time, a ground traversing robot was at a distance too far from earth to make direct human control practical. This has given rise to the development of autonomous systems to improve the e?ciency of these robots,in both their ability to move,and their ability to make decisions regarding their environment ...


Marine Transgression And Vegetation Environments In St. Catherines Island, Georgia, Rachel Luu 2015 Georgia State University

Marine Transgression And Vegetation Environments In St. Catherines Island, Georgia, Rachel Luu

Georgia State Undergraduate Research Conference

No abstract provided.


On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan 2015 Clemson University

On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan

Journal of the South Carolina Academy of Science

Models which can estimate environmental transport of radioactive contaminants in natural and engineered systems are required to 1) deploy effective remediation strategies for contaminated sites, 2) design waste repositories for future waste streams, and 3) ensure protection of human and environmental health in all cases. These models require accurate transport parameters in order to correctly predict how these contaminants will move in the subsurface. This work aimed to determine more accurately the distribution coefficients for radium and strontium sorption to Savannah River Site (SRS) soils. Radium and strontium sorption to the soils was found to be highly dependent upon ionic ...


Relationship Of Surrounding Geology To Well Recovery Properties For Selected Cedarville University Water Supply Wells, Kaitlyn Sturm 2015 Cedarville University

Relationship Of Surrounding Geology To Well Recovery Properties For Selected Cedarville University Water Supply Wells, Kaitlyn Sturm

The Research and Scholarship Symposium

This study was conducted to ascertain the relationship between geology and recovery rates of three selected Cedarville University water supply wells. In order to determine the recovery rates, the three selected wells were individually pumped down and then water level measurements were taken as the water levels rose in the well bore. The collected field data was analyzed and compared to the drillers’ well logs from when the wells were originally drilled. The geologic conditions that were examined for the area immediately surrounding the wells included: bedrock lithology, glacial drift characteristics (type and thickness), ground-surface topography, and bedrock topography. The ...


Buildup And Infill Rates Of Sediment Behind Cedarcliff Falls Dam, Tyler K. Dix 2015 Cedarville University

Buildup And Infill Rates Of Sediment Behind Cedarcliff Falls Dam, Tyler K. Dix

The Research and Scholarship Symposium

Cedarcliff Falls Dam is a small man-made masonry dam that was constructed around 1869. The dam impounds a pool of water that is a half-mile long on Massie’s Creek near Cedarville, Ohio. This project’s goal was to ascertain the infill rate and character of the sediment that had built up since 1869. The field work involved the measurement of water depth through the length of the pool in order to create a bottom-contour map. In addition, the sediment type was examined throughout the pool. This work was accomplished by use of a boat, stadia rod, handheld GPS unit ...


Derivation Of Correction Coefficients For Stream Velocities, Upper Little Miami River Basin, Oh, Matthew S. Cheney 2015 Cedarville University

Derivation Of Correction Coefficients For Stream Velocities, Upper Little Miami River Basin, Oh, Matthew S. Cheney

The Research and Scholarship Symposium

The simplest method of determining stream velocity involves measuring how long it takes a floating object or material to move a certain distance downstream. This study tested a dog toy (mini tennis ball), a 2 inch diameter piece of pumice, a playing card, a full 16.9 oz. water bottle, and milk. The floats were released where the maximum velocity of the stream was found through the use of profiling with a simple flowmeter. The real-time data from a USGS-gaged stream only shows discharge and gage height (stage); it does not show velocity. However, the historic USGS-technician stream-flow-verification data for ...


Chitinozoan Biodiversity In The Ordovician Of Gondwana: An Interval-Free Approach Using The Quantitative Stratigraphic Correlation Program Conop9, Rachel Sales 2015 University of Dayton

Chitinozoan Biodiversity In The Ordovician Of Gondwana: An Interval-Free Approach Using The Quantitative Stratigraphic Correlation Program Conop9, Rachel Sales

Honors Theses

The purpose of this study is to examine the biodiversity patterns of a group of fossil organisms called chitinozoans. Chitinozoans are organic-walled, planktonic microfossils that first appear in the Early Ordovician Period (488 million years ago) and diversify rapidly through the Paleozoic Era. The Ordovician Period was a time of great global climate change, and by studying this group of fossil plankton, we hope to better understand how modern plankton, which are the base of the marine food chain, might respond to climate change. We used a method called constrained optimization (CONOP9) to construct a composite range chart of 152 ...


Core Evolution Driven By Mantle Global Circulation, Peter Olson, Renaud Deguen, Maxwell L. Rudolph, Shijie Zhong 2015 Johns Hopkins University

Core Evolution Driven By Mantle Global Circulation, Peter Olson, Renaud Deguen, Maxwell L. Rudolph, Shijie Zhong

Geology Faculty Publications and Presentations

Reconstructions of the Phanerozoic history of mantle global circulation that include past plate motions are used to constrain the thermochemical evolution of the core. According to our mantle global circulation models, the present-day global average heat flux at the core-mantle boundary lies in the range 80-90 mW.m-2, with peak-to-peak, long wavelength lateral variations up to 100 mW.m-2 associated with compositional and thermal heterogeneity in the D”-layer. For core thermal conductivity in the range k=100-130 W.m-1.K-1 we infer that the present-day outer core is thermally unstable beneath the high seismic velocity ...


Strain Accomodation In The Footwall Of The Rubys Inn Thrust Fault, Hillsdale Canyon, Southern Utah, Claire Cleveland, Rhiannon M. Garrard, Devin M. McLemore, Jeff C.E. Yon, Genevieve Kidman, John S. MacLean 2015 Southern Utah University

Strain Accomodation In The Footwall Of The Rubys Inn Thrust Fault, Hillsdale Canyon, Southern Utah, Claire Cleveland, Rhiannon M. Garrard, Devin M. Mclemore, Jeff C.E. Yon, Genevieve Kidman, John S. Maclean

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Rubys Inn thrust fault in southern Utah has produced several styles of deformation in its footwall. This project describes four exceptionally well exposed examples of strain accommodation, including a mountain-scale, ductile footwall drag fold, cataclastic flexural slip between bedding surfaces of differing competencies, plastically deformed petrified wood within the zone of flexural slip, and cataclastic shear expressed as deformation bands. Such examples show how various lithologies can be deformed into a wide array of structures during a single deformation event. Furthermore, some of these structures result in changes in permeability, which are important for those interested in subsurface fluid ...


Karst Porosity Estimations From Archive Cave Surveys - Studies In The Buda Thermal Karst System (Hungary), Gáspár Albert, Magdolna Virág, Anita Erőss 2015 Eötvös Loránd University, Budapest

Karst Porosity Estimations From Archive Cave Surveys - Studies In The Buda Thermal Karst System (Hungary), Gáspár Albert, Magdolna Virág, Anita Erőss

International Journal of Speleology

The Buda Thermal Karst System is located under the densely populated hills of Budapest. One of its caves (Pál-völgy Cave System) is the longest cave of Hungary with 30.1 km. The research was done in this area as a methodological study to estimate karst porosity parameters of aquifers or hydrocarbon reservoirs. In this study two modeling methods are demonstrated. The volumetric modeling method was primarily aimed to determine the macro-scale (>0.5 m) conduit porosity (referred as macroporosity) of the study area as percentage of the incorporating limestone and marl. This method is based on archive survey data (maps ...


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