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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.
1

Geomorphology of the Green River in Dinosaur National Monument

Grams, Paul E. 01 May 1997 (has links)
Longitudinal profile, channel cross-section geometry, and depositional patterns of the Green River in its course through the eastern Uinta Mountains are each strongly influenced by river -level geology and tributary sediment delivery processes. We surveyed channel cross sections at 1-km intervals, mapped surficial geology, and measured size and characteristics of bed material in order to evaluate the geomorphic organization of the 70- km study reach. Canyon reaches that are of high gradient and narrow channel geometry are associated with the most resistant lithologies exposed at river level and the most frequent occurrences of tributary debris fans. Meandering reaches that are characterized by low gradient and wide channel geometry are associated. with river-level lithology that is of moderate to low resistance and very low debris fan frequency. The channel is in contact with bedrock or talus along only 42 percent of the bank length in canyon reaches and there is an alluvial fill of at least 12 m that separates the channel bed from bedrock at three borehole sites. The influence of lithology primarily operates through the presence of resistant boulders in debris fans that are delivered by debris flows from steep tributaries. The depositional settings created by debris fans consist of (1) channel-margin deposits in the backwater above the debris fan, (2) eddy bars in the zone of recirculating flow below the constriction, and (3) expansion gravel bars in the expansion below the zone of recirculating flow. These fan-eddy complexes are the storage location of about 70 percent. by area, of all fine- and coarse-grained alluvium contained within the canyons above the low-water stage. Immediately adjacent meandering reaches contain an order of magnitude more alluvium by area but have no debris fan-created depositional settings. This study also describes the flood-plain and terrace stratigraphy of the Green River in the eastern Uinta Mountains and changes due to the operations of Flaming Gorge Dam, upstream from the study area. These landforms are vertically aggrading deposits that are longitudinally correlative throughout the 65-km study reach. The suite of surfaces identified includes a terrace that is inundated by rare pre- or post-dam floods, an intermediate bench that is inundated by rare post-dam floods, and a post-dam flood plain that is inundated by the post-dam mean annual flood. Analysis of historical photographs in the study reach shows that both the intermediate bench and post-dam flood plain are landforms that were not present in any of the 6 years for which photographs were examined between 1871 and 1954. Photographic replications also show that gravel bars consisting of bare gravel in 1922 and earlier photographs are now covered by fine-grained alluvium and vegetation . Decreased gravel-bar mobility is indicated by estimates of critical and average boundary shear stress. Comprehensive surficial geologic mapping of the study area indicates that the bankfull channel has decreased in width by an average of about 20 percent.
2

DIVERSITY IN HUNTER-GATHERER LANDSCAPES IN THE NORTH AMERICAN MIDCONTINENT

Thompson, Victor Dominic 01 January 2001 (has links)
The thesis examines changes in hunter-gatherer land-use along lower Cypress Creek, atributary of the Green River located in west-central Kentucky. Presented, are the results of the firstthree years of site survey and museum work conducted by the Cypress Creek Archaeological Project.Analysis of site location and hafted bifaces suggests that, throughout the Holocene, increasingemphasis was placed on certain locations and areas of the landscape. Comparison of the CypressCreek study area with other areas of Archaic research indicate that land-use was highly variable inboth space and time across the North American midcontinent.
3

Geomorphology of the Green River in Dinosaur National Monument

Grams, Paul E. 01 May 1997 (has links)
Longitudinal profile , channel cross-section geometry, and depositional patterns of the Green River in its course through the eastern Uinta Mountains are each strongly influenced by river-level geology and tributary sediment delivery processes. We surveyed channel cross sections at 1-km intervals, mapped surficial geology , and measured size and characteristics of bed material in order to evaluate the geomorphic organization of the 70- km study reach . Canyon reaches that are of high gradient and narrow channel geometry are associated with the most resistant lithologies exposed at river level and the most frequent occurrences of tributary debris fans. Meandering reaches that are characterized by low gradient and wide channel geometry are associated with river-level lithology that is of moderate to low resistance and very low debris fan frequency. The channel is in contact with bedrock or talus along only 42 percent of the bank length in canyon reaches and there is an alluvial fill of at least 12 m that separates the channe l bed from bedrock at three borehole sites. The influence of lithology primarily operates through the presence of resistant boulders in debris fans that are delivered by debris flows from steep tributaries. The depositional settings created by debris fans consist of (1) channel-margin deposits in the backwater above the debris fan, (2) eddy bars in the zone of recirculating flow below the constriction, and (3) expansion gravel bars in the expansion below the zone of recirculating flow. These fan-eddy complexes are the storage location of about 70 percent, by area, of all fine- and coarse-grained alluvium contained within the canyons above the low-water stage. Immediately adjacent meandering reaches contain an order of magnitude more alluvium by area but have no debris fan-created depositional settings. This study also describes the flood-plain and terrace stratigraphy of the Green River in the eastern Uinta Mountains and changes due to the operations of Aarning Gorge Dam, upstream from the study area. These landforms are vertically aggrading deposits that are longiuidinally correlative throughout the 65-km study reach. The suite of surfaces identified includes a terrace that is inundated by rare pre- or post-dam floods, an intermediate bench that is inundated by rare post-dam floods, and a post-dam flood plain that is inundated by the post-dam mean annual flood. Analysis of historical photographs in the study reach shows that both the intermediate bench and post-dam flood plain are landforms that were not present in any of the 6 years for which photographs were examined between 1871 and 1954. Photographic replications also show that gravel bars consisting of bare gravel in 1922 and earlier photographs are now covered by fine-grained alluvium and vegetation. Decreased gravel-bar mobility is indicated by estimates of critical and average boundary shear stress. Comprehensive surficial geologic mapping of the study area indicates that the bankfull channel has decreased in width by an average of about 20 percent.
4

Fishes of The Mammoth Cave Region

Jackson, John Sterling 01 August 1933 (has links)
Extensive surveys of the ichthyological fauna have been made for states bordering Kentucky. An investigation of the literature pertaining to the ichthyology of Kentucky discloses the fact that no detailed investigation has been made of fish life in this state, especially western Kentucky. No record is available of any survey having been made in the section known as the Mammoth Cave Region. The purpose of this survey was to make a species and ecological study of the fishes of the Mammoth Cave Region. Extensive opportunity for ecological studies exists in this region, but only the most important factors were included in this study. A study was made of the species distribution as affected by altitude; the type of water, i.e., whether the water was a river, a lake, a pond, or a sink; and the type of current, i.e., whether a rapidly moving stream, a stream of moderate movement, a still but clear body of water, or stagnant water. Most of the large lakes are of the clear type, while the ponds are of the stagnant type. As the region is naturally divided by Green River into two regions of different geological formations, a study of the species distribution both north and south of the river was made.
5

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.
6

Characterization and interwell connectivity evaluation of Green Rver reservoirs, Wells Draw study area, Uinta Basin, Utah

Abiazie, Joseph Uchechukwu 15 May 2009 (has links)
Recent efforts to optimize oil recovery from Green River reservoirs, Uinta Basin, have stimulated the need for better understanding of the reservoir connectivity at the scale of the operational unit. This study focuses on Green River reservoirs in the Wells Draw study area where oil production response to implemented waterflood is poor and a better understanding of the reservoir connectivity is required to enhance future secondary oil recovery. Correlating the sand bodies between well locations in the area remains difficult at 40-acre well spacing. Thus, interwell connectivity of the reservoirs is uncertain. Understanding the reservoir connectivity in the Wells Draw study area requires integration of all static and dynamic data for generation of probabilistic models of the reservoir at the interwell locations. The objective of this study is two-fold. The first objective was to determine reservoir connectivity at the interwell scale in the Wells Draw study area. To achieve this goal, I used well log and perforation data in the Wells Draw study area to produce probabilistic models of net-porosity for four producing intervals: (1) Castle Peak, (2) Lower Douglas Creek, (3) Upper Douglas Creek, and (4) Garden Gulch. The second objective was to find readily applicable methods for determining interwell connectivity. To achieve this goal, I used sandstone net thickness and perforation data to evaluate interwell connectivity in the Wells Draw study area. This evaluation was done to: (1) assess and visualize connectivity, (2) provide an assessment of connectivity for validating / calibrating percolation and capacitance based methods, and (3) determine flow barriers for simulation. The probabilistic models encompass the four producing intervals with a gross thickness of 1,900 ft and enable simulation assessments of different development strategies for optimization of oil recovery in the Wells Draw study area. The method developed for determining interwell connectivity in Wells Draw study area is reliable and suited to the four producing intervals. Also, this study shows that the percolation based method is reliable for determining interwell connectivity in the four producing intervals.
7

Characterization and interwell connectivity evaluation of Green Rver reservoirs, Wells Draw study area, Uinta Basin, Utah

Abiazie, Joseph Uchechukwu 15 May 2009 (has links)
Recent efforts to optimize oil recovery from Green River reservoirs, Uinta Basin, have stimulated the need for better understanding of the reservoir connectivity at the scale of the operational unit. This study focuses on Green River reservoirs in the Wells Draw study area where oil production response to implemented waterflood is poor and a better understanding of the reservoir connectivity is required to enhance future secondary oil recovery. Correlating the sand bodies between well locations in the area remains difficult at 40-acre well spacing. Thus, interwell connectivity of the reservoirs is uncertain. Understanding the reservoir connectivity in the Wells Draw study area requires integration of all static and dynamic data for generation of probabilistic models of the reservoir at the interwell locations. The objective of this study is two-fold. The first objective was to determine reservoir connectivity at the interwell scale in the Wells Draw study area. To achieve this goal, I used well log and perforation data in the Wells Draw study area to produce probabilistic models of net-porosity for four producing intervals: (1) Castle Peak, (2) Lower Douglas Creek, (3) Upper Douglas Creek, and (4) Garden Gulch. The second objective was to find readily applicable methods for determining interwell connectivity. To achieve this goal, I used sandstone net thickness and perforation data to evaluate interwell connectivity in the Wells Draw study area. This evaluation was done to: (1) assess and visualize connectivity, (2) provide an assessment of connectivity for validating / calibrating percolation and capacitance based methods, and (3) determine flow barriers for simulation. The probabilistic models encompass the four producing intervals with a gross thickness of 1,900 ft and enable simulation assessments of different development strategies for optimization of oil recovery in the Wells Draw study area. The method developed for determining interwell connectivity in Wells Draw study area is reliable and suited to the four producing intervals. Also, this study shows that the percolation based method is reliable for determining interwell connectivity in the four producing intervals.
8

Hydraulic geometry of Green and Birkenhead rivers: Southwestern Coast Mountains, British Columbia

Ponton, John Robert January 1972 (has links)
Green and Birkenhead Rivers are located in the southwestern Coast Mountains of British Columbia, and the drainage in both basins is still strongly controlled by glacial features left after the retreat of the Vashon ice sheet. River slopes are imposed on the upland streams while the slope of the main valley streams is at least partly imposed by the glacial topography. Discharge in the streams is dominated by snowmelt during the summer though peak daily discharges frequently occur in autumn during autumn storms. At-a-station hydraulic geometry curves were determined by least square regression analysis for five sections from Water Survey of Canada gauging records. Velocity shows a more rapid than usual rate of adjustment, and resistance decreases more rapidly than the average as discharge increases. Residual values appear to be distributed about the regression lines in a systematic manner suggesting that the channel form fluctuates systematically over time. Similar results were found for ten other sections in the southwestern Coast Mountains. Downstream hydraulic geometries were determined for Green River and Birkenhead River. Bankfull discharge was assumed to have a constant recurrence interval of 2.33 years for both basins. Channel width shows a greater than usual increase in the downstream direction while velocity appears to remain constant or decrease. / Arts, Faculty of / Geography, Department of / Graduate
9

Biotic and taphonomic response to lake level fluctuations in the Greater Green River Basin (Eocene), Wyoming

Ingalls, Brian R. 05 October 2006 (has links)
No description available.
10

Using Ostracode Dynamics to Track Ecosystem Response to Climatically and Tectonically Induced Lake-Level Fluctuations in Fossil Basin, Green River Basin, Wyoming, USA

McFarland, Andrew J. 06 November 2012 (has links)
No description available.

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