Earth Sciences Commons^™

Origins Of Stable Isotopic Variations In Late Pleistocene Horse Enamel And Bone From Alberta, Nicolle S. Bellissimo

University of Western Ontario - Electronic Thesis and Dissertation Repository

Oxygen and carbon isotopic measurements of coevally formed bone and tooth enamel bioapatite from a modern equid show that these tissues record drinking water and diet isotopic signals in an identical fashion. Hence, data for both tissues can be combined to track movement, dietary changes, and seasonal variability over the animal’s lifetime, and climatic variability over longer time periods. This tool was tested for horses using ten paired tooth and bone samples to reconstruct conditions in Alberta during the Late Pleistocene. While post-mortem isotopic alteration confounded interpretation of the results, two key findings emerged: (i) pre- and post-Last Glacial ...

Comparison Of Topographic Surveying Techniques In Streams, Sara G. Bangen

All Graduate Theses and Dissertations

Fine-scale resolution digital elevation models (DEMs) created from data collected using high precision instruments have become ubiquitous in fluvial geomorphology. They permit a diverse range of spatially explicit analyses including hydraulic modeling, habitat modeling and geomorphic change detection. Yet, the intercomparison of survey technologies across a diverse range of wadeable stream habitats has not yet been examined. Additionally, we lack an understanding regarding the precision of DEMs derived from ground-based surveys conducted by different, and inherently subjective, observers. This thesis addresses current knowledge gaps with the objectives i) to intercompare survey techniques for characterizing instream topography, and ii) to characterize ...

Applications Of Bayesian Statistics In Fluvial Bed Load Transport, Mark L. Schmelter

All Graduate Theses and Dissertations

Fluvial sediment transport is a process that has long been important in managing water resources. While we intuitively recognize that increased flow amounts to increased sediment discharge, there is still significant uncertainty in the details. Because sediment transport---and in the context of this dissertation, bed load transport---is a strongly nonlinear process that is usually modeled using empirical or semi-empirical equations, there exists a large amount of uncertainty around model parameters, predictions, and model suitability. The focus of this dissertation is to develop and demonstrate a series of physically- and statistically-based sediment transport models that build on the scientific knowledge of ...

Exploring Greenhouse Gas Emissions From Beaver Ponds In Southern Rhode Island, Molly K. Welsh, Arthur J. Gold, Kelly Addy, Julia Lazar

Senior Honors Projects

Climate change is one of the largest environmental issues facing humanity today, having the potential to alter fresh water availability, agricultural yields, forest productivity, and global sea levels. As climate change is likely to increase the intensity of extreme weather events, the potential for massive human and financial consequences is of further concern. The Intergovernmental Panel on Climate Change asserts that climate change is due to anthropogenic alterations of the atmosphere’s composition, with additional contributions from natural biochemical processes. In particular, the rapid increase in the concentrations of greenhouse gases (GHGs) in the atmosphere can trigger atmospheric warming as ...

Suspended Sediment Concentrations In Three Tributaries Of The Little River, Chaney Swiney

University of Tennessee Honors Thesis Projects

No abstract provided.

Project Learning In Science: 6th Graders’ Scientific Investigations, Mary Shea Ph. D., Brian Shea

Journal of Inquiry and Action in Education

This article describes the rationale for an enhanced inquiry approach to science education that authentically integrates content knowledge and application skills in a middle school science curriculum. Such pedagogy ensures students’ attainment of national and state standards for learning science and multiple literacies (e.g. language arts and technology) recognized as tools for science achievement; it also provides developmentally appropriate instruction aligned with characteristics of young adolescent learners. Two projects are described; in both, students research, experiment, construct, create, compose, and report, integrating multiple complex skills in ways that simulate real world science investigation. Results demonstrate that students recognize their ...

Shear-Wave Imaging And Birefringence In A Complex Near-Surface Geological Environment, Ali Z. Almayahi

Theses and Dissertations--Earth and Environmental Sciences

Multiple geophysical and geological data sets were compiled, reprocessed, and interpreted using state-of-the-art signal processing and modeling algorithms to characterize the complex post-Paleozoic geology that overlies the southwestern projection of the Fluorspar Area Fault Complex (FAFC) in western Kentucky. Specific data included 21.5 km of SH-wave seismic reflection, 1.5 km of P-wave seismic reflection, 2 km of electrical resistivity, vertical seismic profiles, Vp and Vs sonic-suspension logs, and 930 lithologic borehole logs. The resultant model indicates three general northeast–southwest-oriented fault zones pass through the study area as southwestern extensions of parts of the FAFC. These fault zones ...

Modeling Of Co2-Water-Rock Interactions In A Mississippian Sandstone Reservoir Of Kentucky, Anne M. Schumacher

Theses and Dissertations--Earth and Environmental Sciences

This study examined CO₂-water-rock interactions occurring during a carbon sequestration pilot test into a Mississippian oil reservoir in western Kentucky. New samples (n=62) and archived data, both collected from oil wells, were used to characterize the chemistry of formation waters from the Sugar Creek field in Hopkins County. In addition, core and cuttings samples (n=17) from the reservoir and overlying cap-rocks in, or near, the field were analyzed for bulk and clay mineralogy using X-ray diffraction. Electric logs were used to select sample intervals within the overlying cap-rocks and the center of the producing zones in ...

The Greenhouse Effect At The Molecular Level, Michael Monce

Physics, Astronomy and Geophysics Faculty Publications

The greenhouse effect is generally modeled on a macro scale by designating energy balance for the planetary system. This involves the incoming solar radiation, reflected solar energy, absorbed solar energy at the ground, and subsequent re-radiation at longer wavelengths from the ground. The reradiated energy is then either transmitted out of the system or absorbed by the greenhouse gases and thus changing the overall energy balance.

However, the entire notion of the effects of so-called greenhouse gases hinges on the absorption and reemission of radiation at the individual molecular level. This paper presents an evaluation of that process by utilizing ...

Detecting Geyser Activity With Infrasound, Jeffrey B. Johnson, J. F. Anderson, R. E. Anthony, M. Sciotto

Geosciences Faculty Publications and Presentations

We monitored geyser activity in the Lower Geyser Basin (LGB) of Yellowstone National Park with dual four-element microphone arrays separated by ~ 600 m. The arrays were independently used to identify incident coherent plane wave energy, then conjoint cross beam back-azimuths from the two arrays were used to precisely locate signal sources. During a week in August 2011 we located repeating infrasound events, peaked in energy between 1 and 10 Hz, originating from at least five independent geothermal features, including the episodically erupting Great Fountain, Fountain and Kaleidoscope Geysers, as well as periodic infrasound from nearby Botryoidal and persistent sound from ...

Lava Discharge Rate Estimates From Thermal Infrared Satellite Data At Pacaya Volcano, Guatemala , Hilary A. Morgan

Theses and Dissertations

Time-averaged discharge rates (TADR) were calculated for five lava flows at Pacaya Volcano (Guatemala), using an adapted version of a previously developed satellite-based model. Imagery acquired during periods of effusive activity between the years 2000 and 2010 were obtained from two sensors of differing temporal and spatial resolutions; the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Geostationary Operational Environmental Satellites (GOES) Imager. A total of 2873 MODIS and 2642 GOES images were searched manually for volcanic “hot spots”. It was found that MODIS imagery, with superior spatial resolution, produced better results than GOES imagery, so only MODIS data were used ...

Slope Stability Analysis Of The Pacaya Volcano, Guatemala, Using Limit Equilibrium And Finite Element Method , Patrick. Manzoni

Theses and Dissertations

The Pacaya volcanic complex is part of the Central American volcanic arc, which is associated with the subduction of the Cocos tectonic plate under the Caribbean plate. Located 30 km south of Guatemala City, Pacaya is situated on the southern rim of the Amatitlan Caldera. It is the largest post-caldera volcano, and has been one of Central America’s most active volcanoes over the last 500 years. Between 400 and 2000 years B.P, the Pacaya volcano had experienced a huge collapse, which resulted in the formation of horseshoe-shaped scarp that is still visible. In the recent years, several smaller ...

Comparing Satellite And Ground-Based Observations Of Paroxysmal Degassing Events At Etna Volcano, Italy, Céline L. Mandon

Theses and Dissertations

Mount Etna, Italy, is one of the most active volcanoes in the world, and is also regarded as one of the strongest volcanic sources of sulfur dioxide (SO₂) emissions to the atmosphere. Since October 2004, an automated ultraviolet (UV) spectrometer network (FLAME) has provided ground-based SO₂ measurements with high temporal resolution, providing an opportunity to validate satellite SO₂ measurements at Etna. The Ozone Monitoring Instrument (OMI) on the NASA Aura satellite, which makes global daily measurements of trace gases in the atmosphere, was used to compare SO₂ amount released by the volcano during paroxysmal lava-fountaining events ...

Investigations Into The Degassing And Eruption Mechanisms Of Nyamuragira Volcano, Democratic Republic Of The Congo (Africa) , Elisabet Marie Head

Theses and Dissertations

One of two active volcanoes in the western branch of the East African Rift, Nyamuragira (1.408ºS, 29.20ºE; 3058 m) is located in the D.R. Congo. Nyamuragira emits large amounts of SO2 (up to ~1 Mt/day) and erupts low-silica, alkalic lavas, which achieve flow rates of up to ~20 km/hr. The source of the large SO₂ emissions and pre-eruptive magma conditions were unknown prior to this study, and 1994-2010 lava volumes were only recently mapped via satellite imagery, mainly due to the region’s political instability. In this study, new olivine-hosted melt inclusion volatile (H ...

Remote Sensing Of Volcanic Plumes Using The Advanced Spaceborne Thermal Emission And Reflection Radiometer (Aster). , Lorna Alison Henney

Theses and Dissertations

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) has been used to quantify SO₂ emissions from passively degassing volcanoes. This dissertation explores ASTER’s capability to detect SO2 with satellite validation, enhancement techniques and extensive processing of images at a variety of volcanoes. ASTER is compared to the Mini UV Spectrometer (MUSe), a ground based instrument, to determine if reasonable SO₂ fluxes can be quantified from a plume emitted from Lascar, Chile. The two sensors were in good agreement with ASTER proving to be a reliable detector of SO₂. ASTER illustrated the advantages of imaging a ...

Comparison Of Magnetic Properties And Petrography Between Dykes And Lava Flows From La Cienega, New Mexico And Thunder Bay Area, Canada, Elise A. Desplas

Theses and Dissertations

Data on the evolution of geomagnetic paleointensity are crucial for understanding the geodynamo and Earth’s thermal history. Although basaltic flows are preferred for paleointensity experiments, quickly cooled mafic dykes have also been used. However, the paleointensity values obtained from the dykes are systematically lower than those from lava flows. This bias may originate from the difference in cooling histories and resultant magnetic mineralogies of extrusive and intrusive rocks. To explore this hypothesis, the magnetic mineralogy of two feeder dyke-lave flow systems, from Thunder Bay (Canada) and La Cienega (New-Mexico), has been studied using magnetic and microscopy methods. Within each ...

Geophysical And Geological Analysis Of The Collingwood Member Of The Trenton Formation , Ryan M. Banas

Theses and Dissertations

The Collingwood Member is a mid to late Ordovician self-sourced reservoir deposited across the northern Michigan Basin and parts of Ontario, Canada. Although it had been previously studied in Canada, there has been relatively little data available from the Michigan subsurface. Recent commercial interest in the Collingwood has resulted in the drilling and production of several wells in the state of Michigan.

An analysis of core samples, measured laboratory data, and petrophysical logs has yielded both a quantitative and qualitative understanding of the formation in the Michigan Basin. The Collingwood is a low permeability and low porosity carbonate package that ...

Analysis Of California Coastal Dune And Beach Sand Samples, Dylan J. Mckevitt

The Research and Scholarship Symposium

No abstract provided.

Shellfish Harvest On The Coast Of British Columbia: The Archaeology Of Settlement And Subsistence Through High-Resolution Stable Isotope Analysis And Sclerochronology, Meghan Burchell

Open Access Dissertations and Theses

In many interpretations of hunter-gatherer settlement systems, archaeologists have assumed implicitly or explicitly that a pattern of mobilitybased on seasonally-scheduled movements between different site locations waspracticed. This pattern of mobility is often characterized as a seasonal round, where different locations are used during specific times of the year for different purposes. An implication of this pattern of mobility is that short-term occupation sites are visited annually, approximately at the same time each year and longer-term residential sites can span multiple seasons. To interpret seasonality, indirect indicators are often used but the high-resolution methods presented in this study provide direct evidence ...

Interpreting Stable Carbon And Nitrogen Isotope Ratios In Archaeological Remains: An Overview Of The Processes Influencing The Δ13c And Δ15n Values Of Type I Collagen, Alexander J. Leatherdale

Totem: The University of Western Ontario Journal of Anthropology

The application of isotopic ratio mass spectrometry to archaeological science has produced many important contributions to the study and understanding of ancient human and animal populations. Paleodietary reconstruction through the analysis of stable isotope ratios in skeletal, dental, and soft tissue remains presents another avenue for interpreting the past. The methodology employed to obtain isotopic data from archaeological remains directly influences the types of questions that can be addressed and the interpretation of the data. Furthermore, there are fundamental idiosyncrasies of archaeological specimens and their ante- and post-mortem environments that may influence the results of an isotopic study. This paper ...