Entries by Gelu Costin

Science Advances: Crustal thickening and endogenic oxidation of magmatic sulfur

Ming Tang, Cin-Ty Lee, Wei-Qiang Ji, Rui Wang, Gelu Costin Abstract Porphyry ore deposits, Earth’s most important resources of copper, molybdenum, and rhenium, are strongly associated with felsic magmas showing signs of high-pressure differentiation and are usually found in places with thickened crust (>45 kilometers). This pattern is well-known, but unexplained, and remains an outstanding […]

Nature Communications: Molecular hydrogen in minerals as a clue to interpret ∂D variations in the mantle

B. N. Moine, N. Bolfan-Casanova, I. B. Radu, D. A. Ionov, G. Costin, A. V. Korsakov, A. V. Golovin, O. B. Oleinikov, E. Deloule & J. Y. Cottin Abstract Trace amounts of water dissolved in minerals affect density, viscosity and melting behaviour of the Earth’s mantle and play an important role in global tectonics, magmatism […]

Mineralium Deposita: Hybrid norite and the fate of argillaceous to anhydritic shales assimilated by Bushveld melts

Yudovskaya, M. A., Costin, G., Sluzhenikin, S. F., Kinnaird, J. A., Ueckermann, H., & Abramova, V. D.   Mafic sills of the Marginal Zone are widespread within the footwall of the Bushveld Complex with some of them being enclosed in later Bushveld intrusions. In the central sector of the northern limb of the Bushveld Complex […]

J Petrol: Non-sequential injection of PGE-rich ultramafic sills in the Platreef Unit at Akanani, Northern Limb of the Bushveld Complex: Evidence from Sr and Nd isotopic systematics

Roger N Scoon, Gelu Costin, Andrew Mitchell, Bertrand Moine Abstract The Platreef Unit is a deceptively complex sequence of layered cumulates located in the northern limb of the 2.055 Ga-old Bushveld Complex. The unit includes the Platreef, a thick, richly mineralized stratabound PGE orebody which differs markedly from the comparatively thin, predominantly stratiform Merensky Reef found in the […]

Scientific Reports: Monomineralic anorthosites in layered intrusions are indicators of the magma chamber replenishment by plagioclase-only-saturated melts

Rais Latypov, Sofya Chistyakova, Gelu Costin, Olivier Namur, Steve Barnes & Willem Kruger Abstract The formation of some Earth’s monomineralic igneous rocks appears to be prohibited by constraints imposed by liquidus phase-equilibria on the evolution of mantle-derived magmas. Yet, these rocks exist as stratiform layers in many mafic-ultramafic intrusions. One conspicuous example is monomineralic anorthosites […]

CMP: Bushveld symplectic and sieve textured chromite is a result of coupled dissolution reprecipitation: a comparison with xenocrystic chromite reactions in arc basalt

Marina A. Yudovskaya, Gelu Costin, Vladimir Shilovskikh, Ilya Chaplygin, Matthew McCreesh, Judith Kinnaird Abstract Textures of Bushveld chromite from thin seams and accessory disseminations in the Platreef and the northernmost Waterberg Project area were compared with textures of xenocrystic chromite from mantle xenoliths found in Neogene basalt in the Kurile Island Arc. The sieve-textured to symplectic rims around the resorbed chromite in […]

RevPalBot: Sedimentary organic matter characterization of the Whitehill shales (Karoo Basin, South Africa): An integrated quantitative approach using FE-EPMA and LA-ICP-MS

Sedimentary organic matter characterization of the Whitehill shales (Karoo Basin, South Africa): An integrated quantitative approach using FE-EPMA and LA-ICP-MS Gelu Costin, Annette E. Götz, Katrin Ruckwied Permian black shales of South Africa’s Karoo Basin have been classified as potential unconventional gas resources, the Whitehill Formation of the southern basin parts being the main target […]

Contrib Mineral Petrol: Subduction relics in the subcontinental lithospheric mantle: evidence from variation in the δ18O value of eclogite xenoliths from the Kaapvaal Craton

Subduction relics in the subcontinental lithospheric mantle: evidence from variation in the δ18O value of eclogite xenoliths from the Kaapvaal Craton Ioana-Bogdana Radu, Chris Harris, Bertrand N. Moine, Gelu Costin & Jean-Yves Cottin Mantle eclogites are commonly accepted as evidence for ancient altered subducted oceanic crust preserved in the subcontinental lithospheric mantle (SCLM), yet the […]

Mineralogy and Petrology: Clinopyroxene megacrysts from Marion Island, Antarctic Ocean: evidence for a late stage shallow origin

Clinopyroxene megacrysts from Marion Island, Antarctic Ocean: evidence for a late stage shallow origin James Roberts, Keabetswe D. Lehong, Andries E. J. Botha, Gelu Costin, Frikkie C. De Beer, Willem J. Hoffman and Callum J. Hetherington Clinopyroxene megacrysts (up to 5 cm) from a scoria cone on Marion Island, Antarctic Ocean are zoned, with compositionally distinct low (Al + Ti) and high (Al + Ti) patches arranged haphazardly throughout crystals. […]