Search Results - "Viljoen, K.S."

Eclogite xenoliths from the Lace kimberlite, Kaapvaal craton: From convecting mantle source to palaeo-ocean floor and back by Aulbach, S., Viljoen, K.S.

“…•Trends in REE, HFSE, Eu⁎ suggest low-P picrite protoliths for Lace mantle eclogites.•Protoliths formed by spinel peridotite melting at P∼2.5 GPa and moderate…”
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Ultramafic Carbonated Melt‐ and Auto‐Metasomatism in Mantle Eclogites: Compositional Effects and Geophysical Consequences by Sonja Aulbach, Malcolm Massuyeau, Joshua M. Garber, Axel Gerdes, Larry M. Heaman, K.S. Viljoen

“…Abstract The mineralogy, chemical composition, and physical properties of cratonic mantle eclogites with oceanic crustal protoliths can be modified by…”
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Methane-related diamond crystallization in the Earth's mantle: Stable isotope evidences from a single diamond-bearing xenolith by Thomassot, E., Cartigny, P., Harris, J.W., (Fanus) Viljoen, K.S.

“…Mineralogical studies of deep-seated xenoliths and mineral inclusions in diamonds indicate that there is significant variability in oxygen fugacity within the…”
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Unique chemistry of a diamond-bearing pebble from the Libyan Desert Glass strewnfield, SW Egypt: Evidence for a shocked comet fragment by Kramers, Jan D., Andreoli, Marco A.G., Atanasova, Maria, Belyanin, Georgy A., Block, David L., Franklyn, Chris, Harris, Chris, Lekgoathi, Mpho, Montross, Charles S., Ntsoane, Tshepo, Pischedda, Vittoria, Segonyane, Patience, Viljoen, K.S. (Fanus), Westraadt, Johan E.

“…We have studied a small, very unusual stone, here named “Hypatia”, found in the area of southwest Egypt where an extreme surface heating event produced the…”
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Mineral chemistry and thermobarometry of inclusions from De Beers Pool diamonds, Kimberley, South Africa by Phillips, D., Harris, J.W., Viljoen, K.S.

“…Silicate and oxide mineral inclusions in diamonds from the geologically and historically important De Beers Pool kimberlites in Kimberley, South Africa, are…”
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The trace element composition of silicate inclusions in diamonds: a review by Stachel, Thomas, Aulbach, Sonja, Brey, Gerhard P., Harris, Jeff W., Leost, Ingrid, Tappert, Ralf, Viljoen, K.S.(Fanus)

“…On a global scale, peridotitic garnet inclusions in diamonds from the subcratonic lithosphere indicate an evolution from strongly sinusoidal REE N, typical for…”
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Diamondiferous and barren eclogites and pyroxenites from the western Kaapvaal craton record subduction processes and mantle metasomatism, respectively by Aulbach, Sonja, Viljoen, K.S., Gerdes, Axel

“…Mineral major and trace elements combined with Sr isotopes of clinopyroxene are used to unravel the origins and evolution of mantle eclogite and pyroxenite…”
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Ages and sources of mantle eclogites: ID-TIMS and in situ MC-ICPMS Pb-Sr isotope systematics of clinopyroxene by Aulbach, Sonja, Heaman, Larry M., Jacob, Dorrit E., Viljoen, K.S.

“…Strontium and Pb isotopic compositions of clinopyroxene (cpx) in selected samples from three well-characterised eclogite suites with oceanic crustal protoliths…”
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Effects of low-pressure igneous processes and subduction on Fe3+/ΣFe and redox state of mantle eclogites from Lace (Kaapvaal craton) by Aulbach, S., Woodland, A.B., Vasilyev, P., Galvez, M.E., Viljoen, K.S.

“…Reconstructing the redox state of the mantle is critical in discussing the evolution of atmospheric composition through time. Kimberlite-borne mantle eclogite…”
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Formation of diamondiferous kyanite–eclogite in a subduction mélange by Aulbach, S., Gerdes, A., Viljoen, K.S.

“…Diamond- and kyanite-bearing eclogites from the Lace kimberlite on the Kaapvaal craton have common picritic to gabbroic oceanic protoliths with bimineralic…”
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An unusual suite of eclogitic, websteritic and transitional websteritic-lherzolitic diamonds from the Voorspoed kimberlite in South Africa: Mineral inclusions and infrared characteristics by Viljoen, K.S., Perritt, S.H., Chinn, I.L.

“…A study of the morphology, mineral inclusions, nitrogen content, and nitrogen aggregation state of diamonds from the Voorspoed kimberlite, was conducted. The…”
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Eclogite xenoliths from Orapa: Ocean crust recycling, mantle metasomatism and carbon cycling at the western Zimbabwe craton margin by Aulbach, S., Jacob, D.E., Cartigny, P., Stern, R.A., Simonetti, S.S., Wörner, G., Viljoen, K.S.

“…Major- and trace-element compositions of garnet and clinopyroxene, as well as 87Sr/86Sr in clinopyroxene and δ18O in garnet in eclogite and pyroxenite…”
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Re-healing cratonic mantle lithosphere after the world's largest igneous intrusion: Constraints from peridotites erupted by the Premier kimberlite, South Africa by Zhang, Qiwei, Morel, Melanie L.A., Liu, Jingao, Legros, Hélène, Luguet, Ambre, Viljoen, K.S., Davies, Gareth R., Pearson, D. Graham

“…Constraining the processes that drive the disruption and re-healing of cratonic mantle roots is essential in understanding how cratons evolve. A striking…”
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Stable and radiogenic isotope study of eclogite xenoliths from the Orapa kimberlite, Botswana by Viljoen, K.S., Smith, Craig B., Sharp, Z.D.

“…Eclogite xenoliths from Orapa can be accurately classified as Group I or Group II on the basis of Na 2O in garnet and K 2O in clinopyroxene. Group I xenoliths…”
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Eclogite xenoliths from Kimberley, South Africa — A case study of mantle metasomatism in eclogites by Jacob, D.E., Viljoen, K.S., Grassineau, N.V.

“…Eclogite xenoliths from the Kimberley diamond mine dumps were studied for major, trace elements and oxygen isotopes. The suite consists of typical garnet and…”
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Characterization of fibrous cryptomelane from the todorokite-cryptomelane mineral assemblage at the Sebilo Mine, northern Cape Province, South Africa by Vafeas, Nicholas Andrew, Viljoen, K. S, Blignaut, Lauren Cher

“…A 30-cm hand sample was obtained from the lowermost manganese ore bed, directly below the Kalahari unconformity within the supergene zone, at the Sebilo…”
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Influence of mineralogy and ore texture on pentlandite flotation at the Nkomati nickel mine, South Africa by Mishra, G., Viljoen, K.S., Mouri, H.

“…The influence of ore mineralogy and ore texture on flotation response was studied for 29 samples from the main mineralised zone at Pit 3 of the Nkomati Ni…”
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Trace element chemistry of peridotitic garnets in diamonds from the Premier (Cullinan) and Finsch kimberlites, South Africa: Contrasting styles of mantle metasomatism by Viljoen, K.S., Harris, J.W., Ivanic, T., Richardson, S.H., Gray, K.

“…The purpose of this paper is to provide, discuss, and interpret a comprehensive set of geochemical data (involving major elements as well as Ni, Ti, Sr, Y, Zr,…”
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Geometallurgical characterisation of Merensky Reef and UG2 at the Marikana Mine, Bushveld Complex, South Africa by Dzvinamurungu, T., Viljoen, K.S., Knoper, M.W., Mulaba-Bafubiandi, A.

“…•We conducted milling and flotation experiments on Bushveld ores.•We examined the influence of mineralogy on grinding and flotation.•Abundant plagioclase…”
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The Pipe-15 kimberlite: A new addition to the Wajrakarur cluster of the Wajrakarur kimberlite field, Eastern Dharwar craton, Southern India by Dongre, Ashish N., Viljoen, K. S., Malandkar, M.

“…This paper serves to report, for the first time, on the chemical composition of primary groundmass minerals occurring in a newly discovered kimberlite located…”
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