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The origin of compositional variations in kimberlites based on comparative petrology and geochemistry of samples from four cratonsNARA Subscribed
The term ‘kimberlite’ describes rocks that span a large mineralogical variety including enrichments in mica, carbonates, perovskite, spinel and/or ilmenite. The origin of these compositional variations is addressed here by comparing the petrography, mineral chemistry and bulk-rock as well as groundmass geochemistry of seven representative kimberlite samples (from Wesselton in South Africa; Karowe in Botswana; Diavik and Gahcho...
Experimental differentiation of kimberlitic to carbonatitic melts: crystallization sequence and liquid line of descentNARA Subscribed
Kimberlites are volatile-rich, silica-undersaturated, mantle-derived magmas with an important role in studying mantle geochemistry, yet their compositional evolution during crystallization remains poorly constrained. This study defines the crystallization sequence and liquid line of descent of a reconstructed kimberlitic melt, using high-pressure experiments at 1–3 GPa and 1100–1400 °C. Early crystallization is dominated by ol...
Previous paleolimnological studies demonstrated that the sediments of Garba Guracha, situated at 3950 m asl in the afro-alpine zone of the Bale Mountains of Ethiopia, provide a complete Late Glacial and Holocene paleoclimate and environmental archive. We revisited Garba Guracha in order to retrieve new sediment cores and to apply new environmental proxies, e.g. charcoal, diatoms, biomarkers, and stable isotopes. Our chronology...
The Central Andes play a pivotal role for glacier and climate reconstruction along the American Pole–Equator–Pole transect. Nevertheless, knowledge about late Quaternary palaeoenvironmental changes in this region is extremely limited. With the advent and application of surface exposure dating during the last few years, the establishment of more detailed glacial chronologies could provide important insights into forcings and me...
Land-use effects on phosphorus fractions in Cerrado oxisolsNARA Subscribed
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