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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

The Mississippi River as a political factor in American history, 1784-1788

Tyler, Bruce Marshall. January 1964 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: 8 l. at end.
12

An approach to evaluation of scenic and aesthetic qualities of the Namekagon-St. Croix National Scenic River of Wisconsin

Powell, David Alexander Talbot, January 1975 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1975. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
13

Rainfall and runoff in the Wolf River Basin, Wisconsin

Law, Albert G., January 1960 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1960. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 83-84).
14

Sedimentation on the continental margin off the Orange River and the Namib Desert

Rogers, John 27 September 2023 (has links) (PDF)
This study is the first detailed reconnaissance survey of the bathymetry, bedrock geology and the superficial sediments of the continental margin off the Orange River and the Namib Desert. The study area is bounded by latitudes 25° and 3o0 s. The Orange shelf is up to 100 km wide and 200 m deep, and the Walvis shelf off Lllderitz is up to 80 km wide and 400 m deep, the inner shelf is underlain by. Precambrian bedrock and is usually less than lOi km wide and shallower than 100 m. Tripp Seamount penetrate the upper slope in a depth of 1000 m and rises to within 150 m of sea level, the level of the Orange Banks on the outer orange shelf. South of the Orange River unfossiliferous ferruginous sandstones and mudstones crop out as seaward-dipping scarps on the middle shelf. North of the Orange River, similar scarps are composed of quartzose lime wackestones, identical to a Palaeogene suite on the Agulhas Bank. The shallow outer orange shelf is underlain in places by Upper Middle Miocene nummulitic _limestones, which are overlain by glauconitic conglomeratic phosphorites. Quartz-free algal limestones are found both on the Orange Banks and on the tip of Tripp Seamount. Authigenic pyrite and gypsum were found in two samples of semi-consolidated Neogene clay on the slope off Lüderitz. Pyrite is formed by combining teErigen-. ous adsorbed iron with sulphur released by anaerobic reduction of sea-water sulphate. The dissolution of planktonic foraminiferal tests provides calcium ions which combine with sulphate to form gypsum, once the calcium/sulphate solubility product is exceeded. On the Walvis shelf off LUderitz residual glauconite was reworked from older Neogene sediments, particularly on Lllderitz Bank. North of latitude 26°S residual phosphorite pellets were probably formed in Neogene diatomaceous oozes and then concentrated during a Late-Tertiary regression. Erosion of semi-consolidated .Neogene clays and ?Palaeogene quartzose' limestones. on ·the middle and outer Walvis shelf led to deposition of very fine residual quartz sand south of LUderitz. Coarse quartz ~and was reworked from littoral sandstones on the middle shelf south of the Orange River. The effect on sedimentation in the hinterland of poleward shifts of climatic belts during Quaternary interglacials and the reverse movement during glacials is assessed. Recent terrigenous sediments are derived by erosion of poorly consolidated Karoo sediments in the catchment of the Upper Orange. Erratic but powerful floods transport the sediments to the coast in suspension each summer. At the mouth in tense wave action dominates the submarine delta of the Orange River and fractionates the sediment load. Sand is transported equatorwards by littoral drift and is blown off beaches towards the Namib Sand Sea during violent Trade-Wind gales each sunnner. In contrast, silt and clay are transported polewards by a countercurrent, particularly during westerly winter storms. Recent biogenic sedimentation is controlled by upwelling in the B~nguela Current System, which is most intense off the wind dominated Sperrgebiet, south of LUderitz. Weaker upwelling off the Orange River allows oceanic planktonic foraminifera to penetrate to the middle shelf, whereas on the Walvis shelf in the study area they only reach the outer shelf. Towards latitude 25°s the Benguela Current System decays and interacts with poleward-flowing warm oxygen-poor water. Periodic mass mortalities of oxygen-starved phytoplankton lead to some of the most organic-rich sediments in the world.
15

The keelboat age on western waters

Baldwin, Leland D. January 1941 (has links)
Originally submitted as a doctoral dissertation at the University of Michigan. / "This book is one of a series from the Western Pennsylvania Historical Survey sponsored jointly by The Buhl Foundation, the Historical Society of Western Pennsylvania, and the University of Pittsburgh." Bibliography: p. 237-252.
16

The keelboat age on western waters

Baldwin, Leland D. January 1941 (has links)
Originally submitted as a doctoral dissertation at the University of Michigan. / "This book is one of a series from the Western Pennsylvania Historical Survey sponsored jointly by The Buhl Foundation, the Historical Society of Western Pennsylvania, and the University of Pittsburgh." Bibliography: p. 237-252.
17

Post-flood channel adjustments in the Upper Kickapoo River, Southwest Wisconsin

James, L. Allen. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 237-247).
18

The keelboat age on western waters

Baldwin, Leland D. January 1941 (has links)
Originally submitted as a doctoral dissertation at the University of Michigan. / "This book is one of a series from the Western Pennsylvania Historical Survey sponsored jointly by The Buhl Foundation, the Historical Society of Western Pennsylvania, and the University of Pittsburgh." Includes bibliographical references (p. 237-252). Also available in print ed.
19

Assessing the impact of urbanization on White River water and sediment geochemistry in an agricultural watershed

Snidow, Dean C. January 2009 (has links)
Increased urbanization in the United States and the rest of the world, has led to more research on the effects it has on the local ecology. Urbanization can be defined as the creation of impervious cover in areas previously covered by natural vegetation (forest, grassland or farmland) as well as the potential influence of sewage treatment plants. Small increases in impervious cover can cause noticeable changes in stream chemistry. The goal of this study is to quantify the impact of smaller industrial cities on water and sediment geochemistry in a largely agricultural watershed. The study area is in east-central Indiana along the west fork of the White River and includes the cities of Winchester, Muncie and Anderson. This area is dominated by agriculture and the impact of cities in the region on water chemistry has not been studied. To evaluate this impact, sampling sites were selected up- and downstream of the three cities to characterize White River water chemistry before and after it flows through the cities as well as sewage treatment plants. Sampling was done over the course of one year to obtain samples characteristic of high and low flow river conditions. Samples were analyzed for major cation and anion concentrations as well as total suspended solids. Metals data was also obtained in sediments, although sampled only twice throughout the study. Results show that sediment load, on average, increases on the downstream side as the river flows through urbanized areas. Chemical analyses show that major cations and anions, Na, K, SO4 and Cl, have distinct spikes in concentration on the downstream side of the cities, as well. Na and Cl are specifically linked to human and urbanized activity, and were up to four times higher downstream of urbanized cities. The concentration of other major ions, including Ca, Mg and NO3, was mostly due to agricultural land use and local bedrock geology. Trace metals characteristic of pollution from automobiles, including Cd, Cr and Zn, showed large increases downstream of urban areas as well. This indicates that even in an area that is largely dominated by agriculture, smaller cities have a quantifiable impact to White River water quality. / Department of Geology
20

Abundance of nonprescription pharmaceuticals in central Indiana streams and effects on sediment microbial activity

Bunch, Aubrey R. January 2009 (has links)
Access to abstract permanently restricted to Ball State community only / Indirect effects of human population growth on stream ecosystem function : sediment respiration and nutrient uptake response to nonprescription pharmaceuticals -- Frequency and distribution of nonprescription pharmaceuticals in central Indiana streams. / Access to thesis permanently restricted to Ball State community only / Department of Biology

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