Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 11 of 11 for “"GEOTHERM"”.
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A comparison of melt depletion, thermal structure and metasomatism of proterozoic mantle lithosphere in the Namaqua-Natal and Rehoboth Provinces of Southern Africa
… Rietfontein) lie on or very near the Kaapvaal geotherm and between the 40mWm⁻² and 45mWm⁻² conductive geotherms, demonstrating that the lithospheric mantle in the Rehoboth Province was thermally similar to that of the Kaapvaal craton during the Late Cretaceous. In contrast, peridotites from the …
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Some aspects of the mineral chemistry of the peridotite xenolith suite from the Bultfontein Diamond Mine, Kimberley, South Africa
… have been calculated using three different geothermometers and three geobarometers, and the uncertainties involved in their application have been discussed. Some of the deformed xenoliths appear to have equilibrated at marginally higher temperatures and pressures than the undeformed …
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Elasticity of single-crystal iron-bearing pyrope to 20 GPa and 750 K
… and piclogite, along Earth’s upper mantle geotherm. These velocity models show Vs profiles consistent with seismic observations, although Vp profiles are slightly lower than in seismic models.
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Paleogeothermal Conditions in the Illinois Basin During Late Paleozoic Coalification
… reflectance in deep wells suggests that the paleogeotherm of the basin contain an inflection at the Mississippian-Pennsylvanian boundary. These observations suggest that topographically driven regional flow of hydrothermal fluids through the Upper Paleozoic Lower Paleozoic aquifers raised the …
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The rheology and dynamics of the Precambrian lithosphere – insights from the British Isles
… to post- subduction metamorphic event. Using geotherm modelling, I infer that this event led to partial melting in the mid-to-lower crust, resulting in the development of the microcraton as a strong region. In Chapter Four, I compare the characteristics of the mantle on and off the microcraton …
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Investigation of the upper mantle as a source for contribution to magnetic anomalies
… to magnetic anomalies. Alternatively, the high geotherm and sulfide-rich mantle near the Rio Grande Rift precludes this area from mantle contribution to magnetic anomalies. As first author I prepared samples, ran experiments, processed data, produced figures, wrote the manuscript and applied for …
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Thermobarometry and geochemistry of peridotite xenoliths from the southwestern margin of the Kaapvaal craton, South Africa
… Proterozoic NamaquaNatal Province record geothermal gradients akin to those of cratonic terranes. In contrast, xenoliths sampled during the younger Group I kimberlite magmatism (~ 80 Ma) within the Namaqua-Natal Province record equilibration temperatures which are displaced to higher …
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A detailed investigation into diamond-bearing xenoliths from Newlands Kimberlite, South Africa
… (depending on the classification scheme used). Geothermometry yields temperatures between 920 to 1080 °C, equivalent to pressures between 42 and 58 kbar (based on a 37-38 mW/m 2 geotherm), which lies within the diamond stability field. Re-Os systematics for the diamond-bearing eclogites are …
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High-temperature metamorphism in the western Namaqua-Natal Metamorphic Province (South Africa): implications for low-pressure granulite terranes
… slow, largely isobaric cooling to an ambient geotherm with no significant attending exhumation, are consistent with a long-lived evolution in a continental back-arc mobile belt setting.
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High-temperature metamorphism in the western Namaqua-Natal Metamorphic Province (South Africa): implications for low-pressure granulite terranes
… slow, largely isobaric cooling to an ambient geotherm with no significant attending exhumation, are consistent with a long-lived evolution in a continental back-arc mobile belt setting.
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ΘΕΡΜΟΜΗΧΑΝΙΚΗ ΣΥΜΠΕΡΙΦΟΡΑ ΤΗΣ ΛΙΘΟΣΦΑΙΡΑΣ ΣΤΟΝ ΕΛΛΗΝΙΚΟ ΧΩΡΟ
… MEASUREMENTS AND ESTIMATED HEAT FLOW, PALEOGEOTHERMAL INDICATORS, DEEP GEOPHYSICAL DATA RELATED TO THE CRUST STRUCTURE, RHEOLOGICAL MODELS FOR THE STRENGTH OF THE LITHOSPHERE. OFFSHORE AND WEST OF PARGA THE VERTICAL PRINCIPAL STRESS (ΣΝ) IS INTERMEDIATE BETWEEN ΣΗ AND ΣΗ, IN NW PELOPONNESE …