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 10 of 10 for “"sub-continental lithospheric mantle"”.
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The nature and co-behaviour of volatile and non-volatile elements in the sub-continental lithospheric mantle
The lithospheric mantle represents a critical interface in global volatile cycles because it separates Earth’s convecting mantle from the rigid crust. Nevertheless, the source, abundance and flux of volatiles stored in this reservoir are poorly constrained. In this work, the concentrations of …
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Tracing mantle degassing along the East African Rift using He and C isotopes: a geospatial approach
… fluids and lavas were used as tracers to detect mantle-degassing across the East African Rift. From the literature, a database of R/Ra and δ13C-CO2 values was produced with accompanying isotopic and geochemical data. The data was filtered, removing samples of ambiguous origin, and samples heavily …
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Magmatic And Tectonic Evolution Of Southern Tibet And The Himalaya
… orogen has become the paradigm for continental collision and is central to deciphering continental tectonics. Neogene extension in the orogen is not predicted by plate tectonic theory, and its significance is widely debated.<br></br><br></br>In the Himalaya, north-south extension is …
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Magma genesis beneath active continental rifts
… Rift System (WARS) are two of the largest continental rift systems on Earth, but the processes governing rift dynamics remain controversial. The large volume and distinct chemistry of Cenozoic rift-related lavas, combined with geophysical evidence for low-density mantle underlying both …
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The petrogenesis of Liberian diamondiferous rocks, Man Craton, West Africa
… originate from the convective asthenosphere and sub-continental lithospheric mantle, respectively, however, the genetic link between these rock types is still a debate among researchers. Recently, it has been shown (e.g., in the Dharwar Craton, India) that both kimberlites and lamproites may be …
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Nominally volatile-free mantle minerals: a reservoir for water and fluorine in the Kaapvaal Craton
The extent to which Earth’s sub-cratonic lithospheric mantle acts as a major repository for volatile elements is poorly constrained. This study presents the first systematic investigation into water, fluorine and chlorine storage in nominally volatile-free mantle minerals from sub-cratonic mantle. …
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Geochemical fractionation during melting of sulfide and sulfate bearing mantle lithologies
… at convergent margins, where, crust and oceanic lithospheric mantle subducts beneath an overriding plate and transporting sulfur and other materials from the surface to the deep Earth. A part of the subducted sulfur gets released from the subducting slab to the surrounding mantle at sub-arc …
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Petrology and geochemistry of the diamondiferous K-richteriteand leucite-bearing Kareevlei Kaapvaal lamproite
… believed to be non-diamondiferous or at least sub-economic and as a result, their petrogenesis has remained poorly constrained as the exploration programs focused mainly on the unevolved subvarieties of Kaapvaal lamproites, such as at the Finsch mine. To further assist with the petrogenesis of …
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Classification and petrogenesis of the Tongo dike-01 from the Tongo-Tongoma cluster, Sierra Leone: constraints from bulk rock geochemistry
… the world derive from the same asthenospheric mantle reservoir and their major element chemistry is controlled by the compositions/mineralogy of the lithospheric mantle assimilated during kimberlite evolution. The similarity of the trace element ratios and Sr-Nd-Pb isotopes of the Tongo dike-01 …
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A geochemical study of metasomatised peridotite and marid nodules from the Kimberley pipes, South Africa
… of enrichment processes operating in the sub-continental lithospheric mantle. The metasomatised peridotite suite is divided into garnet peridotites (GP), which contain no texturally equilibrated or primary phlogopite, garnet phlogopite peridotites (GPP), which constitute the most abundant …