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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.
111

A Water Budget and Solute Flux Budget for Waimea River Watershed, Kauai, HI, U.S.A.

Tolworthy, Joseph Harold 21 December 2020 (has links)
Waimea Canyon is a deep V-shaped canyon on the island of Kauai, Hawaii in which the Waimea River and its tributaries flow. The shape and size of the canyon are noteworthy and unusual compared to its contemporary canyons on the Hawaiian Islands which are usually U-shaped or flat bottomed. This could be because there is significantly more physical erosion in Waimea Canyon compared to others. A water budget was created using ArcGIS Pro and data from the University of Hawaii’s rainfall and evapotranspiration atlases, as well as from the United States Geological Survey’s stream gage data. A mass flux was estimated using ArcGIS pro by creating a paleosurface from the ridge points and then finding the mass difference between todays watershed and the watershed with the paleosurface. Weathering reactions were made to model the processes in the watershed. The reactants were found from using oxide percentages of Kauai basalts and inputting them into MELTs to estimate mineralogy. The products were found by analysis of soil and water samples in the area of the Canyon. In the Waimea River watershed approximately 159 t/km2 /yr is removed, of which 56% is by physical erosion. This was compared to the V-shaped Makaweli river watershed where approximately 12% is removed by physical erosion and in the U-shaped Hanalei watershed ≈ 68% is removed. While these differences could be explained by vegetation cover, precipitation, and slope steepness it shows that there is not more physical erosion in Waimea Canyon compared to the others. Thus, the origin of the V-shape of Waimea Canyon remains unexplained.
112

Geomorphic Features and History of the Lower Part of Logan Canyon, Utah

Williams, Edmund J. 01 May 1964 (has links)
Logan Canyon is located east of Logan, Utah, in the Bear River Range. The lower part of Logan Canyon is considered that section of the canyon from its mouth upstream to Tony Grove Canyon, a distance of 22 miles, Figure 1 Some tributary canyons of the lower part of Logan Canyon have been included in this investigation because of their relationship to Logan Canyon. Grassy Flat Canyon, a south tributary of Logan Canyon 4.4 miles from Logan, exhibits several geomorphic features related to the geology of Logan Canyon. Because of its extensive use and close association with Logan Canyon, Tony Grove Canyon is also included. Tony Grove Canyon extends from Logan Canyon northwestward to the crest of the Bear River Range, a distance of about six miles. More than 20,000 feet of Paleozoic rocks ranging in age from Cambrian to Pennsylvanian are exposed in Logan Canyon . Cenozoic deposits are widespread in and near the canyon. The crest of the Bear River Range near Naomi Peak and Tony Grove Canyon was the center of glacial activity during the Pleistocene. During the glaciations of Tony Grove Canyon, Lake Bonneville extended into Logan Canyon and influenced the geomorphic development near the mouth of the canyon. Logan Canyon is vital to the economy of Cache Valley. The canyon is a large part of the Logan River watershed. Logan River passes through three hydroelectric plants in Logan Canyon and supplies culinary and irrigation water for the valley below. Animals and plants of a wide variety are abundant, providing fishing , hunting, and a harvest of forest products. U.S. highway 89 traverses the canyon and carries a large volume of traffic to points within the canyon, as well as to other areas. Logan Canyon is entirely within the Cache National Forest. Improved campsites and recreational facilities, which were used by almost 1.5 million visitors during 1963; according to the U. S. Forest Service, are located throughout the Canyon. Increased recreational and travel use of the canyon has resulted in a demand for more geologic work in this area .
113

Geology of the Summer Ranch and North Promontory Mountains, Utah

Adams, O. Clair 01 May 1962 (has links)
General Statement The Summer Ranch and North Promontory Mountains have not been studied in detail geologically, although the surrounding mountains have been extensively investigated. Within the limits of this area, sedimentary rocks of Mississippian through Permian crop out. Sedimentary and volcanic rocks of Tertiary age are also exposed. Extensive Lake Bonneville deposits underlie the valleys and overlap the foothills. The purposes of this study are: (1) to describe the structure, stratigraphy, and geologic history of the area, (2) to prepare a geologic map of the area, and (3) to relate the stratigraphic features of this area to those of the surrounding region. Location of Area The area studied is bordered on the north by the Utah-Idaho state line and on the east by Blue Creek Valley. Utah State Highway 83 and Great Salt Lake form the southern boundary and Curlew Valley, south-southwest from Snowville, Utah, defines the western limit (Figure 1). The mapped area lies completely .within Box Elder County and covers a total of about 529 square miles. The Utah division of the Thiokol Chemical Corporation is located near the southeast corner of the mapped area. Field Work Initial field work was begun in August of 1960. Investigation of the 3 mapped area plus near-by areas was carried on continuously through September of that year and intermittently until June, 1961. Access roads are mainly unimproved but are passable by passenger car. Water is available at most of the ranches in the adjoining valleys and at several springs in the North Promontory and Summer Ranch Mountains. Structural and stratigraphic details were plotted on vertical aerial photographs in the field. Information was subsequently transferred to a topographic map at a scale of 1:62, 500, which was enlarged from a U. S. Geological Survey map, then traced on a transparent overlay. Stratigraphic sections were measured with a Brunton compass or with a steel tape. Previous Investigations No previous complete geologic investigation has been made of the area covered by this report. Various local features within the mapped area have been studied. Walter (1934, p. 178-195) describes the structural relations of the Hansel Valley earthquake of 1934. Additional investigation concerning the structure of Hansel Valley was conducted by Adams (1938). Tertiary stratigraphy of Cache Valley was studied by Adamson (1955). Adamson reported the occurrence of tuffaceous rocks, similar to those in Cache Valley, in association with basalt flows near Snowville, Utah. Smith (1953, p. 74) diagrams the southern limit of the Snake River basalt flows and showed that they covered the northern part of the area concerned in the present investigation.
114

Mitigation, Monitoring, and Geomorphology Related to Gully Erosion of Archaeological sites in Grand Canyon

Petersen, Paul A. 01 May 2003 (has links)
Gully erosion has been damaging archaeological sites in Grand Canyon during the last several decades, and there is a need to protect these features through mitigation, monitoring, and better geomorphic understanding. The purpose of this study was to assess the effectiveness of erosion-control structures , determine the accuracy and utility of aerial photogrammetry for monitoring gullies , and understand the geomorphology of the erosion . We performed total-station surveys and other data collection during February and October , 2002, at nine study sites in eastern and western Grand Canyon. Erosion-control structures are more prone to be damaged by flow when they are placed in reaches of very high local gradient. Treatments are generally successful in slowing erosion or causing deposition of sediment, but damaged erosion-control structures were shown to be less effective than intact structures, and actually increase local erosion in cases. Aerial photogrammetry was performed on four eroding archaeological sites in western Grand Canyon in March and October 2002 in order to assess the accuracy and change-detection utility of this tool. Accuracy was assessed on several different levels by comparing photogrammetry data to ground-survey data, and mean absolute vertical error ranged from 6-10 cm. Error of manual photogrammetry digital terrain models (DTMs) increased with topographic ruggedness and decreased with greater photogrammetric point density. Mean error reached a minimum of 5 cm for March and 6.5 cm for October when the ratio of point density to topographic ruggedness was ~40. Ground surveys and repeat photography indicated that two study gullies eroded or aggraded during the study period by 10-20 cm, but these changes were mostly undetected in the photogrammetry DTMs. Repeat ground surveys showed that gullies erode most at knickpoints and in steep reaches , and that new knickpoints tend to form in relatively steep reaches of a given channel. An area-slope erosion threshold was identified for the study sites and applied in a GIS-based model at four sites to show areas that exceed the threshold and are sensitive to gully erosion . Overall results show an upcatchment control of gully erosion and suggest that baselevel changes due to Glen Canyon Dam operation are subordinate controls.
115

Fuel Load and Plant Community Dynamics of Bryce Canyon National Park

Wight, Doug W. 01 May 1994 (has links)
A comprehensive fuel load assessment of all plant communities in Bryce Canyon National Park is provided. Fuel loads by community type are pooled into "fuel type associations" based on similarity in predicted fire behavior, and the fuel type associations are mapped throughout the Park. For each fuel type association, a series of fire behavior simulations is presented describing expected rates of spread and intensities for typical conditions in each month of the fire season and for a worst-case scenario. These fire behavior predictions provide guidelines for writing prescribed burning prescriptions or for quickly assessing the need for possible fire suppression and the amount of effort required to suppress particular fires.
116

Geologic Feasibility of Dam and Reservoir Sites, Blacksmith Fork Canyon, Utah

Buenaventura, Alfredo Capistrano 01 May 1968 (has links)
Two areas along the Blacksmith Fork River, in the Bear River Range southeast of Logan, Utah, were studied as sites for a storage dam and reservoir. An earth dam, 150-200 feet high, and a reservoir of 15,000-20,000 acre-feet are contemplated by the Bureau of Reclamation, U.S. Department of Interior. The lower area, located about 7 miles east of the mountain front, involves two possible dam sites on limestone. Thick overburden is present in the canyon bottom and on the right abutments. The upper area, located about 2 miles south of the headquarters of the Hardware Ranch, includes two possible dam sites on quartzite. The quartzite at the upstream site was found, by drilling and testing, to be extensively fractured; the downstream site has not been drilled. Acceptable topographic settings are present at both of these sites. Geological factors, as well as a difficult road relocation necessitated by the reservoir, exclude the lower area. It is recommended that the downstream site of the upper area be explored by means of a drilling program. A systematic evaluation of constructio materials near this site, based on appropriate excavations, is also required. (58 pages)
117

Quaternary Geology and Landscape Evolution of Eastern Grand Canyon, Arizona

Anders, Matt D. 01 May 2003 (has links)
Tectonics and drainage evolution are controlling overall landscape incision in eastern Grand Canyon. Superimposed on downcutting are dynamic responses of hillslopes, tributary streams, and the Colorado River to glacial-interglacial climate cycles. Five tributary stream fill terraces have been identified, and luminescence dating indicates aggradation was occurring 50- 34 ka {S3), 12-7 ka (S2), and 5-3.5 ka (S1). Seven Colorado River fill terraces have been identified, and luminescence and U-series dating indicate deposition was occurring 343-322 ka (M5), 151-118 ka (M4), and 71-64 ka (M3). Aggradation by the Colorado River in eastern Grand Canyon begins during glacial advances and continues into the subsequent climate reversals. It appears to be driven by increases in sediment yield associated with glacial advances in headwater areas and glacial conditions elsewhere in the Colorado River drainage basin. Local catchments have buffered responses to climate change, with stream aggradation being driven by changes in sediment yield and hydrology of hillslopes. Tributary stream aggradation during full-glacial conditions (S3) is caused by a decrease in precipitation intensity and an increase in bedrock weathering. Aggradation during glacial-interglacial transitions (S2) and interglacial conditions (S1) is the result of increased erosion of older surficial deposits and decreases in vegetation cover. In the context of the current working model for the response of drylands to climate change, eastern Grand Canyon is distinct in that significant tributary stream aggradation occurs during full-glacial climate conditions and throughout the tributary drainage networks. This suggests that landscape response to climate change in semiarid environments may be slightly different than in arid settings. Bedrock incision by the Colorado River has been occurring at a rate of 0.13 mm/yr over middle-late Quaternary time. The technique used to make this calculation involves comparing snapshots of the river at analogous positions within its aggradation-incision cycles. The most accurate calculation results from tracing the elevation of the valley bottom through time. This method requires robust age control, but is advantageous because true bedrock incision is calculated and possible error associated with the use of short time intervals and thick fill deposits is eliminated.
118

Comparative Analysis of Ceramics from Three Great Houses and One Small House Site in Southeast Utah

Harris, Rachel Marie 01 December 2014 (has links) (PDF)
Ceramics from three Utah great houses, Bluff, Cottonwood Falls, and Edge of the Cedars, were analyzed and compared with ceramics from Three Kiva Pueblo, which is not a great house site but was occupied contemporarily. Data on jar and bowl rim diameters were considered to understand great house feasting dynamics. Cooking jars with large rim diameters were more common at Three Kiva than they were at the great houses. This suggests that Three Kiva residents prepared large batches of food more frequently than great house residents. Distributions of Mancos Black-on-white bowl diameters were very similar at great houses and Three Kiva, but Three Kiva had bowls with larger diameters than those found at the great houses. Jar sizes suggest it is possible that feasting at great houses took place with a potluck model; however, bowl sizes suggest that Three Kiva also hosted feasts. Data on ceramic origins were considered to look for direction and strength of relationships with outside regions. All of the great houses had higher proportions of imported ceramics than Three Kiva, suggesting that great house residents interacted with people from other regions more frequently. All sites had large proportions of imported ceramics from the Kayenta region. All great house sites had Chuskan and Cibolan sherds, suggesting interaction with Chaco Canyon. Proportions of imported ceramics and the regions from which they came varied for each site, indicating that site residents maintained independent connections to people living in other regions.
119

The Economic and Social History of Bingham Canyon, Utah, Considered With Special Reference to Mormon-Gentile Synthesis

Addy, George M. 01 January 1949 (has links) (PDF)
This paper will be confined to the northern portion of the range though it might be noted that the topographical descriptions of the Bingham district apply in a general way to the southern district also. The northern Oquirrhs contain a number of sizeable canyons running either east or west from a central ridge seven thousand to eight thousand feet in altitude. Bingham Canyon, one of the largest of these, is located on the eastern slope of the range and drains into Salt Lake Valley.
120

GIS and Satellite Visibility: Viewsheds from Space

Germroth, Matthew Ryan 24 May 2005 (has links)
The Global Positioning System (GPS) has recently become the significant mapping tool for millions of customers worldwide, providing its users with accurate terrestrial positions almost instantaneously. The functionality of a GPS receiver depends on the number of satellites to which it can establish an unobstructed line of sight. Current satellite availability prediction tools perform satellite visibility predictions without considering terrain or structures that block GPS signals, a major issue in mountainous and urban areas. This paper describes a new Geographic Information Systems (GIS) tool, a customization of ArcGIS named Satellite Viewsheds, which predicts satellite visibility for any place and time while considering line of sight obstructions. Satellite Viewsheds requires a raster surface model, the test date and time, and the orbital properties of the satellites. It produces grids depicting the number of visible satellites and optimal viewing time for every cell in the grid. Satellite Viewsheds allows users to avoid areas of signal loss and choose the best time to map using their GPS receivers. The field test of Satellite Viewsheds proved that the tool performs satellite visibility predictions consistently and accurately. The research outlined in this paper indicates that Satellite Viewsheds is the first tool of its kind. / Master of Science

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