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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

Distribution of Macroinvertebrates in the Green River Below Flaming Gorge Dam, 1963-1965

Pearson, William D. 01 May 1967 (has links)
This study was undertaken to determine the effects of rotenone applied during a fish control operation in September 1962 and the installation of Flaming Gorge Dam in November 1962 upon the distribution of invertebrates in the Green River. Since these two events, the river has changed from a warm, turbid stream to a cold, clear trout stream for about 45 miles below the dam. Totals of 234 bottom samples and 394 drift samples were collected between the dam and Ouray, Utah (166 miles below the dam). The species composition of the fauna above Carr Ranch was much simpler during 1964-65 than the reported pre-impoundment composition. Below Carr Ranch the species composition of the invertebrate fauna has changed little. Bottomfauna densities were highest near the dam (max. 6347/ft. 2) and decreased with increasing distance below the dam. Population densities below Carr Ranch (42.7 miles below the dam) appeared to be similar to reported pre-impoundment densities. Drift rates of Baetis nymphs and Simuliidae larvae were highest near the dam. Illumination, population density. of other organisms, and water temperature had significant effects on drift-net catches of Baetis and Simuliidae. Turbidity and water - level fluctuations had important effects under certain circumstances, while date, dissolved oxygen, and depth of water had little effect on drift - net catches.
12

The origins of rapids in the lower New River Gorge, West Virginia

Moore, Dawn Anne. January 1999 (has links)
Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains ix, 61 p. : ill. (some col.), maps (some col.) Includes abstract. Includes bibliographical references (p. 55-59).
13

Development of Recreational use Patterns at Flaming Gorge Reservoir, 1963-1965

Hewston, John Guthrie 01 May 1966 (has links)
Three major occurrences in recent years have emphasized a need for new data concerning reservoir-based recreation patterns. These occurrences were: (1) the increased rate of construction of new, large reservoirs by federal agencies; (2) the increasing demand for recreation space and fishing water; and (3) the establishment of large national recreation areas around federal reservoirs.
14

Simplified Framework Evaluation of Large Water Resource Project Impacts

Clowes, Brian Woodbridge 01 January 1988 (has links)
The document most frequently used to support a water resource project's economic feasibility is the commercial benefit-cost analysis, which quantifies tangible and direct project consequences. The objective of this type of analysis is simply to maximize net monetary benefits. This analysis assigns an arbitrary monetary value to ecological and social disruptions, if it does not ignore these effects entirely. An improvement on this method is the social benefit-cost analysis, which assesses sane intangible costs such as air and noise pollution. Unfortunately, even the social analysis usually neglects the sometimes profound effects that a large water resource project has upon quality of life, particularly with regards to massive relocations. The purpose of this dissertation is to resolve these problems by presenting a method by which a water resource study team may use five unique viewpoints - technical, organizational, personal, social, and environmental - to quantify and compare the true benefits and costs of project construction and operation. The study team begins by rigorously documenting the three general categories of project consequence (economic, social and environmental) and assigning each benefit or cost a relative value within category according to perceived positive or negative effects. The second step is to use these quantifications to produce three impact vs. dam height curves. The final and most difficult step in this study process is to assign a relative weight to the respective economic, social, and enviromental impact clusters, depending on national priorities and the biases and personal viewpoints of the decisiomaker (s). The final product of this procedure is a single curve which is used to further investigate and assess the overall feasibility of a water resource project and the 'optimum' range of dam heights. All of the possible impacts of a large water resource project, whether they be tangible or intangible, should be investigated in order to produce an authentic indicator of project efficiency. The only way to insure that all impacts are properly accounted for is to perform an exhaustive examination of a water resource project from the five perspectives mentioned above. The body of this dissertation is an example analysis based upon the proposed Three Gorge Dam and Reservoir on the Yangtze River in the People's Republic of China. This project will be the world's largest power plant at 13,000 megawatts. Because of its size, anticipated impacts, and the interest it has generated all over the world, the Three Gorge project is considered the ideal subject of a comprehensive multiple perspective analysis as described in this study.
15

Sublime, Contemplation and Repose: Reawakening Nuttallburg from West Virginia’s Industrial Descent

Blake, Benjamin R. 18 June 2019 (has links)
No description available.
16

A Petrographic and Diagenetic Study of the Whirlpool Sandstone from Outcrops in the Hamilton and Niagara Gorge Areas

Calow, Russell W. 04 1900 (has links)
<p> Four measured sections of the Whirlpool Sandstone were prepared from outcrops in the Niagara Gorge and Hamilton areas. Sedimentary structures and constituents present in the lower two-thirds of the unit are consistent with the sandy braided fluvial depositional model. proposed by Salas [1983]. The upper one-third of the unit has been deposited in a near shore, shallow marine environment. All samples have been classified as Quartzarenites, or Sublitharenites after Folk [1974] and the source of the Whirlpool lies to the southeast in primarily pre-existing sediments, with some input from low grade metamorphic and hydrothermally veined terrains. </p> <p> Cathodoluminescent microscopy has proven to be a safe, relatively inexpensive, easy to use method, that offers a great deal of new information. The technique's only drawback is the gradual destruction of thin sections by the electron beam. The CL study demonstrated that pressure solution was not the source of the massive, pore occluding, mesodiagenetic quartz cement. Since very low diagenetic temperatures have been calculated for the Whirlpool in the study area [360C]; the local generation of silica would be impossible. Instead, it has been suggested that silica was carried in by saturated pore fluids that had migrated up-dip from source areas deep within the depositional basin to the southeast. Similarly, pyrite was precipitated as H2S bearing fluids migrated through the unit. These reducing fluids also produced the reduced zone at the top of the Queenston Formation. The H2S was produced during the maturation of hydrocarbons. Calcite cement is more abundant in the upper marine units of the Whirlpool. This suggests that the source of the calcite was local detrital carbonate in the upper marine units. Quartz cementation ceased when the porosity had been reduced sufficiently to inhibit the passage of the migrating pore fluids. Thus, the calcite cement precipitated from static pore fluids. The local detrital carbonate was dissolved by the acidic fluids that carried in the silica. This Ca+2 rich fluid was prevented from mixing with the bulk porewater and calcite precipitation occurred due to an increase in C02 by the decay of organic detritus in the upper marine units. The major proportion of secondary porosity was formed during mesodiagenesis by the dissolution of calcite. The pore fluids became undersaturated with respect to calcite when local intershale water was released into the porewater. The formation of dolomite cement was in response to a decrease in the amount of available iron relative to magnesium due to the precipitation of ferroan calcite. The zonation of the dolomite reflects rapid changes in porewater composition. Four morphologies of illite have been identified: two represent direct precipitation from alkaline, K+ rich solution; one may be detrital in origin, or it could represent illite that has been mechanically infiltrated down into the sand after deposition; and the fourth is a mixed layer assemblage that has been formed by the replacement of earlier clays by illite. The oil and gas found in the Whirlpool Sandstone in the Lake Erie area have probably migrated up-dip from source areas deep within the depositional basin to the southeast. </p> / Thesis / Bachelor of Science (BSc)
17

Sourcing Oldowan and Acheulean Stone Tools at Oldupai Gorge (Tanzania)

Favreau, Julien January 2024 (has links)
Hominins habitually moved across landscapes to forage for resources, which can be investigated by the probabilistic attribution of stone tools to raw material sources. The sources that were available to Pleistocene hominins at the UNESCO World Heritage Site of Oldupai Gorge (Tanzania) have been studied for over a half-century. However, limited reference collections have prevented detailed investigations on the degree to which hominins transported stone tools. The primary goal of this dissertation was to identify the locations and distances over which Oldowan and Acheulean hominins transported raw materials at Oldupai Gorge and interpret the results in the context of the human evolutionary record. Fieldwork consisted of sampling metamorphic and volcanic outcrops to supplement an existing reference collection. An equally important fieldwork component consisted of conducting excavations at four occupation sites, including, from oldest to youngest, Ewass Oldupa (Oldowan), Elang’ata Oljurusi (Acheulean), Engaji Nanyori (Acheulean), and Emurutoto (Acheulean). Laboratory work consisted of studying artefact collections to obtain general information about toolmaking practices, and characterising geological samples and stone tools at the macroscopic and geochemical levels for comparative analyses using computational statistics. The overarching aim of this dissertation was to investigate whether the shift from Oldowan to Acheulean toolmaking was accompanied by equally more complex landuse strategies amidst progressive aridification. Informed by probabilistic sourcing results, the evidence presented herein indicates that the Oldowan to Acheulean transition in the Oldupai basin was accompanied by more focalised landuse. Yet, both Oldowan and Acheulean hominins altered their mobility to variable environments ranging from woodlands to steppe deserts. These behavioural responses represent possible explanations for the adaptive radiation of hominin populations across, and out of, Eastern Africa during the Early and Middle Pleistocene. / Dissertation / Doctor of Philosophy (PhD) / Hominins habitually moved across landscapes to forage for resources, which can be investigated by sourcing the raw materials that were fashioned into stone tools. The raw material sources at the UNESCO World Heritage Site of Oldupai Gorge (Tanzania) have been studied for over a half-century. However, limited reference collections have prevented thorough investigations on the degree to which hominins transported tools during the Pleistocene. Informed by the systematic sampling of metamorphic and volcanic outcrops, macroscopic and geochemical data were used to source Oldowan and Acheulean artefacts excavated from four occupation sites across the Oldupai Gorge study area. The evidence presented herein indicates that the shift from Oldowan to Acheulean toolmaking was accompanied by more focalised landuse amidst growing aridity. Yet, both Oldowan and Acheulean hominins altered their mobility to variable environments. This represents a plausible explanation for the adaptive radiation of hominin populations into increasingly diverse biogeographic zones through time.
18

A geochemical study of the Eagle Creek Formation in the Columbia River Gorge, Oregon

Carlin, Rachel Ann 01 January 1988 (has links)
The Early Miocene Eagle Creek Formation, a series of volcanic mudflows and debris flows, is exposed in the Columbia River Gorge about 64 kilometers east of Portland, Oregon. Eighty-seven samples were analyzed using instrumental neutron activation analysis for trace element concentrations. Eleven samples were analyzed by Dr. Peter Hooper at Washington State University using X-ray Fluorescence for major element chemistry. These data were used to determine that the Eagle Creek Formation compositionally ranges from andesite to dacite.
19

Defining the Terroir of the Columbia Gorge Wine Region, Oregon and Washington, USA Using Geographic Information Systems (GIS)

Whitney, Hilary 30 June 2015 (has links)
The Columbia Gorge Wine Region (CGWR) is an emerging wine producing area that extends for about 100km along the Columbia River in Oregon and Washington State in which the number of vineyards, wineries and physical terroir conditions have yet to be defined. To better understand the physical factors affecting Oregon and Washington wine, this project analyzes climate, topography, geology and soil at vineyards in the CGWR. This was accomplished using Geographic Information Systems, existing earth science databases and field work. The region, which includes the Columbia Gorge American Viticulture Area (AVA) and the southwest portion of the Columbia Valley AVA, is home to 82 vineyards, 513 hectares (1268 acres), 37 wineries and 41 different varieties of Vitus Vinifera. Vineyards range in elevation from 29 to 548 meters (95 to 1799 feet). Vintner responses to a grower's survey suggest that twenty-eight grape varieties account for 98% of the estimated grape variety acreage, with Pinot Noir being the most widely planted grape variety in both AVAs. The boundaries of each climatic regime were mapped based on 1981-2010 PRISM data, the Winkler Index (Amerine and Winkler, 1944) updated by Jones et al. (2010) and climatic maturity groupings designed for Oregon (Jones et al., 2002; Jones et al., 2010). Three Winkler climate regimes are represented within the CGWR, including regions Ia, Ib, and II from the Winkler Index (Jones et al., 2010). The diversity in regimes allows for a diversity of grape varieties to be planted within the regime. The average growing season temperatures and growing degree days, respectively, from 1981-2010 calculated for vineyards ranges from 13.7°C (55.7°F) to 17.7°C (63.9°F) and 871 for °C (1567 for °F) to 1664 for °C (2994 for °F) respectively. 58% of the vineyards are characterized in an intermediate climatic regime, 29% are within a cool climatic regime, 9% are within a warm climatic regime and 4% are on the boundaries between a cool, intermediate or warm regime. 80% of the vineyards are within Regions Ia and Ib characterized by the Winkler Index, and 20% are within Region II. The growing degrees days calculated for the CGWR are similar those measured in the Willamette Valley, Oregon, Burgundy, France, Umpqua Valley AVA in Oregon and Bordeaux wine region in France. All of the soils currently being used to grow grapes are well-drained and within a xeric moisture regime, which are favorable conditions for viticulture. 30 soil series are represented among the vineyard sites, with the Chemawa Series (Underwood Mountain) and Walla Walla Series (eastern portions) being the dominant soil series used to grow grapes. Majority of the soils contain a silt loam texture. Soil Survey data for Oregon and Washington suggest that loess is extensive in the CGWR, with 46.5% of the total vineyard acreage planted on soils formed in loess. The Missoula Floods also greatly influenced the texture and age of the soil in this region, with skeletal textures being close to the Columbia River. Other common geological deposits at vineyards in the CGWR include, Quaternary Basalt (19.6%), Missoula Flood deposits (9.1%), The Dalles Formation (8.0%), Columbia River Basalt Group (7.5%), Pliocene Basalt (3.0%), Quaternary Surficial deposits (3.0%), lahars (2.3%) and Quaternary Basaltic Andesite and Andesite (0.9%). Common geological deposits, soil series, and climate conditions at vineyard sites vary spatially in the region, and therefore it is suggested that future work focus on separating the region into separate climatic sub-AVA regimes to better reflect the diversity in terroir conditions.
20

A Location Analysis of Vandalism to the Rock Art of the Columbia River Gorge National Scenic Area

Wilt, Julia J. 26 May 1993 (has links)
Archaeological sites in the New World are the fragile and non-renewable remains of cultures which flourished for thousands of years prior to European contact and displacement. Sites which escape the effects of erosion and development often fall victim to vandalism. Cultural resources, including rock art and other archaeological sites, are protected by state and federal laws which prohibit the removal or disturbance of the sites, whether from development or from vandalism. Vandalism is frequently seen as a problem for law enforcement rather than a problem for cultural resource management. Management plans which include cultural resource protection provisions and guidelines often focus on threats to cultural resources from development, and omit planning which targets vandalism. The rock art sites of the Columbia River Gorge National Scenic Area ("Scenic Area") have been affected by developments such as The Dalles Dam and by the vandalism. In this study, the nature and degree of vandalism to the rock art sites in the Scenic Area is considered in the context of public awareness of, and access to, these sites. Rock art sites which are easily located and which have been the focus of public awareness are hypothesized to be the most severely vandalized. To test this hypothesis, fifteen of the 44 rock art sites in the Scenic Area were selected for study, and were assessed for kind and degree of vandalism, and means and ease of access. The results of analysis yielded two statistically significant associations of variables which support the hypothesis: an association between vandalism and public awareness of sites, and an association between vandalism and the primary means of access. The analysis suggests that public awareness is one of the most important issues which land managers must address when designing cultural resource protection plans.

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