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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

Distribution, abundance, and population characteristics of shoal bass in tributaries of the Chattahoochee River, Alabama

Stormer, David G. January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Includes bibliographic references (ℓ. 74-84)
2

Developing a domestic water supply for Winnipeg from Shoal Lake and Lake of the Woods: the Greater Winnipeg Water District Aqueduct, 1905 – 1919

Ennis, David 07 April 2011 (has links)
The water source for The City of Winnipeg is Shoal Lake near the Manitoba-Ontario border, 145km east of the city, and is delivered by a gravity powered system known as the Winnipeg Aqueduct. It was built during World War 1. The system is 150km in length, primarily in an enclosed conduit operating under open channel flow, and crosses eight rivers. The project was built by the Greater Winnipeg Water District. The concept of the Water District, is administration, the design of the aqueduct’s components, the contract administration, and the construction procedures employed in implementing the system are explained. The purchase and topographical modification of land belonging to the First Nation residents of Shoal Lake Band 40 was essential to the development of the project. There are ongoing issues for this First Nation arising from that purchase.
3

Developing a domestic water supply for Winnipeg from Shoal Lake and Lake of the Woods: the Greater Winnipeg Water District Aqueduct, 1905 – 1919

Ennis, David 07 April 2011 (has links)
The water source for The City of Winnipeg is Shoal Lake near the Manitoba-Ontario border, 145km east of the city, and is delivered by a gravity powered system known as the Winnipeg Aqueduct. It was built during World War 1. The system is 150km in length, primarily in an enclosed conduit operating under open channel flow, and crosses eight rivers. The project was built by the Greater Winnipeg Water District. The concept of the Water District, is administration, the design of the aqueduct’s components, the contract administration, and the construction procedures employed in implementing the system are explained. The purchase and topographical modification of land belonging to the First Nation residents of Shoal Lake Band 40 was essential to the development of the project. There are ongoing issues for this First Nation arising from that purchase.
4

Salt Control on Sedimentary Processes in Early Pleistocene: Ship Shoal South Addition Blocks 349-358, Gulf of Mexico.

Syarif, Munji 30 September 2004 (has links)
The interpretation of 3D seismic data from Ship Shoal South Addition Blocks 349-358, Gulf of Mexico shows a complex interaction between salt, faults, and sedimentary strata. Reconstruction of the geometry of early Pliestocene (about 3.65 Ma) through recent salt and associated sediments reveals the evolution of a supralobal basin in the study area. The basin depocenter shifted from the northeastern part to the center of the study area through time. A small, bulb-shaped, salt-stock structure occurs in the northwest, and a salt sheet structure is present in the southeastern part of the study area. Those structures are part of a pennant-shaped structure bounded by counter regional faults trending northeastward. Salt movements created instability and triggered extensive faulting of the overlying strata. Three-dimensional reconstruction suggests that salt blocked the sediment during the early Pleistocene. The sediment was diverted around the salt high on both east and west sides of the salt body to the southwest and southeast. Stratigraphic interpretation of the interval between 1.35 Ma and 1.95 Ma led to the identification of a highstand systems tract (HST), a transgressive systems tract(TST), and two lowstand systems tracts (LST). The strata are developed normally in the depocenter area, whereas the strata at the basin margin were deformed by salt movement and faulting. Each systems tract is uniquely associated with a certain seismic facies. Three seismic facies were identified associated with LST, TST, and HST. Additionally, seismic sections reveal channel geometries in the LST. Seismic attribute analysis elucidates facies distribution in the systems tracts. Because of its ability to move, to divert sediment, to create instability, and to block sediment transport pathways, salt exercises the main control on the sedimentary processes in the study area.
5

Taxonomy and diversity of the sponge fauna from Walters Shoal, a shallow seamount in the Western Indian Ocean region

Payne, Robyn Pauline January 2015 (has links)
>Magister Scientiae - MSc / Seamounts are poorly understood ubiquitous undersea features, with less than 4% sampled for scientific purposes globally. Consequently, the fauna associated with seamounts in the Indian Ocean remains largely unknown, with less than 300 species recorded. One such feature within this region is Walters Shoal, a shallow seamount located on the South Madagascar Ridge, which is situated approximately 400 nautical miles south of Madagascar and 600 nautical miles east of South Africa. Even though it penetrates the euphotic zone (summit is 15 m below the sea surface) and is protected by the Southern Indian Ocean Deep-Sea Fishers Association, there is a paucity of biodiversity and oceanographic data. Thus, a multidisciplinary cruise was initiated in May 2014 on the FRS Algoa as a component of the African Coelacanth Ecosystem Programme. The research presented here focuses exclusively on the diversity, bathymetric distribution patterns and biogeographic affiliations of the sponge fauna of this seamount. Sponges were sampled using SCUBA and a roughed epibenthic sled, from the peak and down two opposing slopes of the seamount, to a depth of 500 m. Two hundred and fifty-five sponge specimens were collected, comprising 78 operational taxonomic units (OTU’s), 23 of which are known to science, 26 which are possibly new, 16 that could only be identified to higher taxonomic levels and 13 that could only be designated as morphospecies. Thirteen OTU’s are formally described here, four which are known, and nine possibly new to science. Sponge assemblages demonstrated no significant difference according to location on the shoal, with several species shared by both the western and eastern flanks. In contrast, sponge assemblages differed significantly according to depth, with the mesophotic zone (31 – 150 m) acting as a transition between the shallow (15 – 30 m) and submesophotic (> 150 m) zones. Species richness and the number of putative new species was highest in the submesophotic zone. Biogeographical affiliations were found with both the Western Indo-Pacific and Temperate Southern African realms based on the 23 known species recorded. No affiliations were found with the West Wind Drift Island Province, as has been documented previously for the fish fauna of this seamount, possibly due to the incomplete nature of the online database (World Porifera Database) used to assess affinities. Thirty-nine percent of the known sponge species found at Walters Shoal Seamount are widely distributed in the Indian Ocean, 35% are found exclusively within the Western Indian Ocean region, with this study representing the southernmost distribution record for several of these, and 26% have a restricted distribution around South Africa. / National Research Foundation (NRF)
6

The glacial geomorphology of the Shoal Lake area, Labrador /

Cowan, William Richard January 1967 (has links)
No description available.
7

The glacial geomorphology of the Shoal Lake area, Labrador /

Cowan, William Richard January 1967 (has links)
No description available.
8

Understanding factors that control seagrass reproductive success in sub-tropical ecosystems

Darnell, Kelly Marie 22 October 2014 (has links)
Seagrasses are submerged marine plants that provide essential ecosystem functions, but are declining in abundance worldwide. As angiosperms, seagrasses are capable of sexual reproduction, but also propagate asexually through clonal rhizome growth. Clonal growth was traditionally considered the primary means for seagrass propagation. Recent developments in genetic techniques and an increasing number of studies examining seagrass population genetics, however, indicate that sexual reproduction is important for bed establishment and maintenance. Few studies have investigated the reproductive biology and ecology of sub-tropical seagrass species, although this information is necessary for effective management and restoration. This work investigates the influence of pore-water nutrients on flowering, water flow on seed dispersal, consumption on seed survival, and describes the reproductive phenology in Texas for the two dominant seagrass species in the Gulf of Mexico: turtle grass (Thalassia testudinum) and shoal grass (Halodule wrightii). These species exhibit distinctive reproductive seasons that span summertime months, but reproductive output varies spatially and temporally. Results of an in situ nutrient enrichment experiment indicate that turtle grass produces fewer flowers (but more somatic tissue) when exposed to high pore-water ammonium than when exposed to low pore-water ammonium, suggesting that nutrient loading has the potential to reduce seagrass reproductive output. Seed consumption may also limit reproduction and recruitment in some areas, as laboratory feeding experiments show that several local crustaceans consume shoal grass and turtle grass seeds and seedlings, which do not survive consumption. Dispersal experiments indicate that seed movement along the substrate depends on local water flow conditions, is greater for turtle grass than shoal grass, and is related to seed morphology. Under normal water flow conditions in Texas, turtle grass secondary seedling dispersal is relatively minimal (< 2.1 m d⁻¹) compared to primary dispersal, which can be on the order of kilometers, and shoal grass secondary seed dispersal can be up to 1.1 m d⁻¹, but seeds are likely retained in the parent meadow. Results from this work can be used when developing seagrass management, conservation and restoration actions and provide necessary information concerning a life history stage whose importance was historically under-recognized. / text
9

Studies on The Coastal Changes in Southwestern Taiwan Since The 17 Century

Hsu, Shih-Hsiang 02 June 2011 (has links)
The main purpose of this research is to investigate the scouring effect on the west coast of Taiwan that has been caused by the natural disasters and the human activities since 17 centuries. The studies consist of the depicting of maritime topography, the data collection of sea meteorology, and the data mapping with the use of Google Earth software. The present research employed the satellite image data and the achieve maps from literature for accurately quantifying the coastal changes in south-western Taiwan. The changing process of coastal line around the south-western Taiwan including the influences of natural and artificial factors of long and short period is also investigated. The surveys has divided the coastal changes into three periods, 17th century to 1904 A.D., 1940 A.D. to 1945 A.D., and 1945 A.D. to present. In the first period, the isotope dating and historical data we used to identify the coastal line. The results of this research showed that the main element of coastal line shift in the west coast between 17th ~20th century is caused by the sink-transport of enriched river-based sources. During the second period, the data collection with the use of better precision instruments from colonial government, the sea area of Yunlin produced series of shoal from 1904 to 1945. The coast area expanded outward 26 km. On the contrary, the shoals in the sea area of Tainan were shifted inward due to lacking of sink-transport source, but the coasts remained less deposited in this period because the influence of artificial facilities construction. By artificial development, the coast was seriously corroded frequently since 1945 that leaded to the shoals reduction and disappearance. The coast was no longer to receive the sink transport source because of highly artificial coastal development, such as land reclamation, fishing port construction, and coastal protection measures to prevent from further continuously erosion around the coasts. It is necessary to emphasize that the theorem, practical and research aspect can be applied to integrate the coastal plan and development in the future. It is imperative for government to initiative on the aspects of monitoring the topography, river basin, ecology area, and sea meteorology with the use of GIS system to establish database. Moreover, the government should evaluate the feasibility of coast construction, revise the laws to protect coast and provide the guidelines on the coast plan and development in the marine environment. Finally, this research addresses the need of precautionary approach against the natural disaster.
10

Investigation of time-lapse 4D seismic tuning and spectral responses to CO₂-EOR for enhanced characterization and monitoring of a thin carbonate reservoir

Krehel, Austin January 1900 (has links)
Master of Science / Department of Geology / Abdelmoneam Raef / Advancements, applications, and success of time-lapse (4D) seismic monitoring of carbonate reservoirs is limited by these systems’ inherent heterogeneity and low compressibility relative to siliciclastic systems. To contribute to the advancement of 4D seismic monitoring in carbonates, an investigation of amplitude envelope across frequency sub-bands was conducted on a high-resolution 4D seismic data set acquired in fine temporal intervals between a baseline and eight monitor surveys to track CO₂-EOR from 2003-2005 in the Hall-Gurney Field, Kansas. The shallow (approximately 900 m) Plattsburg ‘C Zone’ target reservoir is an oomoldic limestone within the Lansing-Kansas City (LKC) supergroup – deposited as a sequence of high-frequency, stacked cyclothems. The LKC reservoir fluctuates around thin-bed thickness within the well pattern region and is susceptible to amplitude tuning effects, in which CO₂ replacement of initial reservoir fluid generates a complex tuning phenomena with reduction and brightening of amplitude at reservoir thickness above and below thin-bed thickness, respectively. A thorough analysis of horizon snapping criteria and parameters was conducted to understand the sensitivity of these autonomous operations and produce a robust horizon tracking workflow to extend the Baseline Survey horizon data to subsequent Monitor Surveys. This 4D seismic horizon tracking workflow expedited the horizon tracking process across monitor surveys, while following a quantitative, repeatable approach in tracking the LKC and maintaining geologic integrity despite low signal-to-noise ratio (SNR) data and misties between surveys. Analysis of amplitude envelope data across frequency sub-bands (30-80 Hz) following spectral decomposition identified geometric features of multiple LKC shoal bodies at the reservoir interval. In corroboration with prior geologic interpretation, shoal boundaries, zones of overlap between stacked shoals, thickness variation, and lateral changes in lithofacies were delineated in the Baseline Survey, which enhanced detail of these features’ extent beyond capacity offered from well log data. Lineaments dominated by low-frequency anomalies within regions of adjacent shoals’ boundaries suggest thicker zones of potential shoal overlap. Analysis of frequency band-to-band analysis reveals relative thickness variation. Spectral decomposition of the amplitude envelope was analyzed between the Baseline and Monitor Surveys to identify spectral and tuning changes to monitor CO₂ migration. Ambiguity of CO₂ effects on tuning phenomena was observed in zones of known CO₂ fluid replacement. A series of lineaments highlighted by amplitude brightening from the Baseline to Monitor Surveys is observed, which compete with a more spatially extensive effect of subtle amplitude dimming. These lineaments are suggestive of features below tuning thickness, such as stratigraphic structures of shoals, fractures, and/or thin shoal edges, which are highlighted by an increased apparent thickness and onset of tuning from CO₂. Detailed analysis of these 4D seismic data across frequency sub-bands provide enhanced interpretation of shoal geometry, position, and overlap; identification of lateral changes in lithofacies suggestive of barriers and conduits; insight into relative thickness variation; and the ability of CO₂ tuning ambiguity to highlight zones below tuning thickness and improve reservoir characterization. These results suggest improved efficiency of CO₂ -EOR reservoir surveillance in carbonates, with implications to ensure optimal field planning and flood performance for analogous targets.

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