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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.
31

Deep-Basinal Lithium-Rich Brines

Palmer, Timothy 04 May 2018 (has links)
The hydrocarbon producing rocks of the Upper Jurassic in the northern Gulf of Mexico are known to contain lithium-rich brines. However, the genesis of the lithium-rich water is not very well understood. Analysis of hydrogeochemical data indicates that the brines are enriched in bromide, Calcium, Lithium, and sodium, and depleted in potassium, magnesium, and sulfate. Considering this, hydrogeochemical, petrographic, and X-ray Powder Diffraction (XRD) data shows that the brines have been significantly altered relative to the original composition of the water, by salt dissolution, freshwater mixing, and dolomitization. Based on the results of this study, the ore-grade lithium brine is being enhanced by the same stratigraphic and geochemical controls that is depositing dolomite in the Upper Jurassic reservoirs of the northern Gulf of Mexico.
32

Hydrocarbon Content of the Manitoulin Dolomite on Manitoulin Island

Cameron, John A. 05 1900 (has links)
<p> The Manitoulin Formation on Manitoulin Island consists of a lower biostrome extending across the island and an upper biohermal accumulation just south of Manitowaning. </p> <p> Viscible hydrocarbon accumulations occur in the bioherm, mostly contained in the more porous framework corals Paleofavosites and Palaeophyllum. Hydrocarbons found in other sample sites across the island show a very low bulk weight per cent and are of no economic significance. </p> <p> The bulk of the hydrocarbon was likely formed in lower carbonates near the centre of the Michigan Basin. Petroleum is also thought to have been introduced with solutions which formed calcite deposits. </p> / Thesis / Bachelor of Science (BSc)
33

Petrology of Hydrothermal Zebra Dolomite at the Cove Mine, McCoy Mining District: Northern Fish Creek Mountains, Lander County, Nevada

Schnell, Andrew J. 09 June 2014 (has links)
No description available.
34

The implementation of a geo-environmental decision support system for development on dolomite / Pieter Pretorius

Pretorius, Pieter January 2012 (has links)
Due to the inherent hazardous characteristics associated with dolomite and development on dolomite, quantification of the stability attributes related to dolomite is essential. In large parts of South Africa, development on dolomite is inevitable due to the location thereof. The purpose of this study is to define an implementation framework for decision-making with regards to development on dolomite. The decision-making process is based on a dolomite stability investigation conducted by AGES North West (AGES, 2012) within Sarafina, Ikageng. The results from this study are interpreted by means of a decision support system that is based on the geo-environmental setting of the study area and the geotechnical properties related to the subsurface profile. This includes but is not limited to: Geo-environmental site conditions: • Drainage • Topography • Geophysical conditions • Regional geological conditions • Local geological conditions • Regional groundwater conditions • Local groundwater conditions Geotechnical stability of the dolomite based on the hazard characterisation and evaluation procedures: • Percussion drilling data • Receptacle development • Mobilisation agencies • Potential surface manifestation development space • Nature and mobilisation potential of the blanketing layer • The bedrock morphology These parameters are all inter-related and affect each other in various ways. During the study the importance of site specific observations and interpretations are emphasized. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013
35

The implementation of a geo-environmental decision support system for development on dolomite / Pieter Pretorius

Pretorius, Pieter January 2012 (has links)
Due to the inherent hazardous characteristics associated with dolomite and development on dolomite, quantification of the stability attributes related to dolomite is essential. In large parts of South Africa, development on dolomite is inevitable due to the location thereof. The purpose of this study is to define an implementation framework for decision-making with regards to development on dolomite. The decision-making process is based on a dolomite stability investigation conducted by AGES North West (AGES, 2012) within Sarafina, Ikageng. The results from this study are interpreted by means of a decision support system that is based on the geo-environmental setting of the study area and the geotechnical properties related to the subsurface profile. This includes but is not limited to: Geo-environmental site conditions: • Drainage • Topography • Geophysical conditions • Regional geological conditions • Local geological conditions • Regional groundwater conditions • Local groundwater conditions Geotechnical stability of the dolomite based on the hazard characterisation and evaluation procedures: • Percussion drilling data • Receptacle development • Mobilisation agencies • Potential surface manifestation development space • Nature and mobilisation potential of the blanketing layer • The bedrock morphology These parameters are all inter-related and affect each other in various ways. During the study the importance of site specific observations and interpretations are emphasized. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013
36

Microbially mediated porosity enhancement in carbonate reservoirs experiments with samples from the Salem, Sligo, and Smackover formations /

Coffey, Melody Roy, January 2004 (has links)
Thesis (M.S.) -- Mississippi State University. Department of Geosciences. / Title from title screen. Includes bibliographical references.
37

Structural Geology of Eastern Part of the Malad Summit Quadrangle, Idaho

Shearer, Jay Nevin 01 May 1975 (has links)
The mapped area represents the eastern three-fourths of the Malad Summit Quadrangle, Idaho. It lies mainly in the Bannock Range of southeastern Idaho. The northern and southern margins of the area are 25.5 miles and 17.0 miles, respectively, north of the Idaho-Utah State Line. The Caddy Canyon Formation of Late Precambrian age is the oldest exposed stratigraphic unit. The youngest unit, exclusively of Precambrian age, is the Mutual Formation. The Brigham Formation is considered to be of Late Precambrian to Early Cambrian(?) age. Younger formations of Cambrian to Silurian age are present. The Precambrian units, as well as the Brigham, consist chiefly of quartzite. Younger Paleozoic units are primarily limestone and dolomite. The Precambrian and Paleozoic units are unconformably overlapped by the Wasatch and Salt Lake Formations of Tertiary age. A major thrust fault is widely exposed in the mapped area. It places various formations of early Paleozoic age in thrust contact with the Brigham Formation. Several minor thrust faults are also present. The thrust faulting is related to the Laramide orogeny which was active in western United States from late Jurassic into Eocene. Normal faults, in the mapped area, trend generally north-south x and east-west. The north-south faults, characteristic of the Basin and Range province, are responsible f or most of the relief in the area. The normal faulting began as early as Oligocene and has continued intermittently to the present.
38

Study on the dissolution of lime and dolomite in converter slag

Deng, Tengfei January 2012 (has links)
In the present study, the dissolution mechanism and rate of lime, limestone and dolomite in converter slag was studied. Lime dissolution in stagnant slag was studied first and dissolution of lime, limestone and dolomite under forced convection were carried out by new experimental setup. Dissolution of different CaO samples into stagnant converter slags was carried out in a closed tube furnace at 1873K. In the case of CaO-‘FeO’-SiO2 slag, the dissolution of CaO rod in the stagnant slag was retarded after the initial period (2 minutes). A dense layer of 2CaO∙SiO2 was found to be responsible for the total stop of the dissolution. It could be concluded that constant removal of the 2CaO∙SiO2 layer would be of essence to obtain high dissolution rate of lime. In this connection, it was found necessary to study the dissolution of lime in moving slag. In order to obtain reliable information of lime dissolution under forced convection, the commonly used rotating rod method was examined. Both CFD calculation and cold model experiments showed evidently that the mass transfer due to radial velocity introduced by forced convection was zero if the rod was centrally placed in a cylindrical container. A new experimental design was therefore developed. A cube was placed in the crucible and stirred by Mo rod along with slag. The whole system could be quenched in order to maintain the state of the system at high temperature. A linear relationship between normalized length and time was obtained for lime dissolution. Different lime samples showed big difference in dissolution rate. It was found that the main mechanism of CaO dissolution in slag was due to the removal of 2CaO∙SiO2 layer. Decomposition and dissolution of limestone and dolomite in slag at 1873 K were studied. The decomposition was carried out both in argon and in slag under argon atmosphere. The decomposition process was simulated using Comsol. The results showed evidently that the decomposition of limestone and dolomite was controlled mostly by heat transfer. It was also found that the decomposition of limestone product: CaO had very dense structure, no matter the sample was decomposed in slag or in argon. The slow decomposition and the dense CaO layer would greatly hinder the dissolution of lime in the slag. The present results clearly indicate that addition of limestone instead of lime would not be beneficial in converter process. Discontinuous 2CaO∙SiO2 layer along with MgO∙Fe2O3 particles was found on the surface of the dolomite sample. Some 2CaO∙SiO2 islands were found in the vicinity of the sample in the slag, which revealed therefore that the dissolution was dominated by the peeling-off of the layer of 2CaO∙SiO2-MgO∙Fe2O3 mixture. 2CaO∙SiO2, (Mg, Fe)Oss along with super cooled liquid phases were found inside dolomite sample close to the surface. 2CaO∙SiO2 phase was replaced gradually by 3CaO∙SiO2 towards the centre of the decomposed sample. / <p>QC 20120829</p>
39

Milankovitch orbital forcing control on shallow-water carbonate cyclicity and early dolomitization: insights from the lower Cretaceous Cupido platform, NE Mexico

Altobi, Younis Khamis 28 August 2008 (has links)
Not available / text
40

Milankovitch orbital forcing control on shallow-water carbonate cyclicity and early dolomitization : insights from the lower Cretaceous Cupido platform, NE Mexico

Altobi, Younis Khamis, 1977- 18 August 2011 (has links)
Not available / text

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