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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Reproductive success and environmental contaminants among bald eagles in Placentia and Bonavista Bays, Newfoundland /

Dominguez, Laura, January 1999 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 90-105.
12

The breeding biology and status of the bald eagle on the Chippewa National Forest

Fraser, James Dempsey. January 1981 (has links)
Thesis (Ph. D.)--University of Minnesota, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 223-235).
13

Reproductive success and environmental contaminants among bald eagles in Placentia and Bonavista bays, Newfoundland

Dominguez, Laura, January 1999 (has links) (PDF)
Thesis (M.S.)--Memorial University of Newfoundland, 1999. / Includes bibliographical references (leaves 90-105).
14

Diagenetic modifications of the Eagle Ford Formation : implications on chemical and physical properties

Mcallister, Richard January 2017 (has links)
This thesis investigates the impacts of diagenesis on the Late-Cretaceous Eagle Ford Formation (Fmn) in south-west Texas. This was achieved utilising many techniques such as of outcrop and core analysis, standard petrographic techniques (including cathodoluminescence [CL] and scanning electron microscopy [SEM]), and geochemical analysis (x-ray diffraction [XRD], stable isotope analysis of C and O within inorganic minerals and Rock Eval pyrolysis). The bulk of diagenetic products and textures were identified via petrographic techniques, with geochemical analysis confirming interpretations based on visual observations. This thesis shows the Eagle Ford Fmn is a calcareous, organic-rich mudstone containing eight distinct lithofacies, which have all been directly impacted by burial diagenesis. The Lower Eagle Ford Fmn mainly comprises of dark organic and clay-rich lithofacies which represent a classic source rock with interbedded carbonate rich lithofacies. The Upper Eagle Ford Fmn is organic and clay-poor, with the bulk of lithofacies carbonate dominated and heavily cemented. An initial anoxic, open marine depositional environment which transitions into an oxic deepening environment is inferred during deposition of the Eagle Ford Fmn. Early, microbial derived redox reactions have precipitated authigenic calcite and pyrite within the Eagle Ford Fmn. Authigenic calcite infills and preserves biogenic debris (mainly planktonic and benthic foraminifera), with pyrite framboids post-dating the carbonate cements. Kaolinite infilling biogenic debris is also a common occurrence indicating it is also an early diagenetic product. Smectite is converted to mixed layer I/Sand illite during deep burial processes at similar depths and temperatures to hydrocarbon generation and expulsion. Authigenic quartz cements precipitate within primary porosity and on top of carbonate cements. Chlorite is observed as the last mineral precipitated in the Eagle Ford Fmn, often pseudomorphed from kaolinite within the micritic matrix. Diagenesis has had the greatest impact on porosity distribution in the Eagle Ford Fmn. The organic, clay-rich lithofacies contain little intra/inter-crystalline porosity with the bulk observed as clay-held or organic porosity. Meanwhile the carbonate-rich lithofacies contain mainly intra-crystalline porosity. Concretions are a common feature observed in the Lower Eagle Ford Fmn outcrops. Four concretion types were identified and studied using a variety of petrological and geochemical techniques. Diagenesis plays a major role in all concretions types. However, primary factors such as sea level fluctuation, sediment input and tectonic activity also have key impacts on the formation of concretions.
15

The influence of perch tree distribution and abundance on bald eagle distribution on the northern Chesapeake Bay, Maryland /

Chandler, Sheri Kay. January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 49-55). Also available via the Internet.
16

Behavior and age class structure of wintering northern bald eagles (Haliaeetus leucocephalus alascanus) in western Utah

Joseph, Ronald A. 16 July 1977 (has links)
Bald Eagles in Cedar and Rush Valleys of western Utah were studied from 1975 to 1977. Arriving in mid-November, the eagles departed in mid-March. A statewide Bald Eagle census revealed 200 to 300 birds. Wintering eagle populations have remained stable for the past 10 years. Immatures comprised 35% of the population in 1975-76 and 33% in 1976-77. While Black-tailed jackrabbits are the primary food source of wintering eagles in western Utah, other mammalian carrion serve as supplementary food items. Eagles utilized 4 communal night roosts. Three day communal roosts were located on south facing slopes. The social existence of Bald Eagles on the wintering grounds may have survival value for immatures.
17

Reproductive success and nesting periodicity of a pair of African Crowned Eagles breeding in KwaZulu-Natal

Malan, G January 2005 (has links)
The African Crowned Eagle, Stephanoaetus coronatus, is a large raptor with a particularly long breeding cycle, even considering its size (Newton 1979). The incubation period is 49–51 days, the nestling period is 104–115 days and the length of the post-fledging period is contentious and varies considerably within its distribution in Africa (Steyn 1982). In some regions where the bird breeds biennially, this period is up to 350 days (Brown and Amadon 1989, Shultz 2002), whereas in other regions the post-fledging period is shorter as pairs bred annually, even for nine years in succession (Vernon 1984). The reason for this discrepancy has been ascribed to environmental quality and seasonal variability, and differences in the main prey base, densities and mortalities between populations (Newton 1979, Jarvis et al. 1980, Steyn 1982, Vernon 1984, Boshoff et al. 1994, Shultz 2002). Furthermore, it is unclear if the fledglings disperse from the nesting area of their own free will or are evicted by the parents (Brown 1966, Oatley 1970).
18

Assessment of the Mexican Eagle Ford Shale Oil and Gas Resources

Morales Velasco, Carlos Armando 16 December 2013 (has links)
According to the 2011 Energy Information Agency (EIA) global assessment, Mexico ranks 4th in shale gas resources. The Eagle Ford shale is the formation with the greatest expectation in Mexico given the success it has had in the US and its liquids-rich zone. Accurate estimation of the resource size and future production, as well as the uncertainties associated with them, is critical for the decision-making process of developing shale oil and gas resources. The complexity of the shale reservoirs and high variability in its properties generate large uncertainties in the long-term production and recovery factors of these plays. Another source of uncertainty is the limited production history. Given all these uncertainties, a probabilistic decline-curve analysis approach was chosen for this study, given that it is relatively simple, it enables performing a play-wide assessment with available production data and, more importantly, it quantifies the uncertainty in the resource size. Analog areas in the US Eagle Ford shale were defined based on available geologic information in both the US and Mexico. The Duong model coupled with a Markov Chain Monte Carlo (MCMC) methodology was used to analyze and forecast production of wells located in the previously defined analog sectors in the US Eagle Ford shale. By combining the results of individual-well analyses, a type curve and estimated ultimate recovery (EUR) distribution for each of the defined analog sectors was obtained. These distributions were combined with well-spacing assumptions and sector areas to generate the prospective-resources estimates. Similar probabilistic decline-curve-analysis methodology was used to estimate the reserves and contingent resources of existing wells. As of March 2013, the total prospective resources (P90-P50-P10) for the Eagle Ford shale in Mexico (MX-EFS) are estimated to be 527-1,139-7,268 MMSTB of oil and 17- 37-217 TSCF of gas. To my knowledge, this is the first oil estimate published for this formation in Mexico. The most attractive sectors based on total estimated resources as well as individual-well type curves are located in the southeast of the Burgos Basin and east-west of the Sabinas basin. Because there has been very little development to date, estimates for reserves and contingent resources are much lower than those for prospective resources. Estimated reserves associated with existing wells and corresponding offset well locations are 18,375-34,722-59,667 MMSCF for gas and zero for oil. Estimated contingent resources are 14-64-228 MSTB of oil and 8,526-13,327- 25,983MMSCF of gas. The results of this work should provide a more reliable assessment of the size and uncertainties of the resources in the Mexican Eagle Ford shale than previous estimates obtained with less objective methodologies.
19

The ecology and conservation of Mackinder's eagle owls (Bubo capensis mackinderi) in central Kenya in relation to agricultural land-use and cultural attitudes /

Ogada, Darcy L. January 2007 (has links)
Thesis (Ph.D. (Zoology & Entomology)) - Rhodes University, 2008.
20

A model of contaminant transport, Saline Valley Aquifer, Gallatin County Illinois

Cox, Ryan William 01 December 2013 (has links)
The Saline Valley Conservancy District (SVCD) formed in 1980 to provide a stable source of water to many communities in Southern Illinois. The SVCD well field located in the thickest, most productive region of the Saline Valley Aquifer lies directly adjacent to a reclaimed coal mine. Subsurface movement and surface discharge from the mine has been shown to be responsible for deterioration of water quality in the surrounding area, including the aquifer. Previous studies conducted in the region have addressed water supply issues and simulated contaminant transport from the reclaimed mine. The limited scope of these models did not extend to natural hydrogeological boundaries. This study extended the model boundaries to natural boundaries including the Saline River to the south, the Wabash and Ohio Rivers to the east, and the bedrock high pinch-out and fining valley textures to the west. The flow model uses parameters from each study as a base then calibrated to 18 discrete head measurements. Initial contaminant transport runs using values from previous studies show successful mine reclamation except for surface discharge to a nearby ditch from well pumping. An analysis was performed that varied parameters to determine if any likely scenarios may cause the plume to travel farther than anticipated. These scenarios include things such as cessation of surface discharge, increasing contaminant source load, and altering recharge and hydraulic conductivity. In all cases sulfate concentrations in the SVCD production wells modeled up to 155mg/L which is under the EPA drinking water guideline for sulfate. Three wells in particular, SVCD-1, SVCD-4, and SVCD-7 never model higher than 7mg/L indicating that several wells lie outside the influence of the sulfate plume. Based on the results of the scenario analysis, the mine can shut off remediation pumping without overly contaminating the SVCD water supply.

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