| | Journal (article/letter/editorial) | Neoproterozoic ‘anomalous’ kimberlites of Guaniamo, Venezuela: mica kimberlites of ‘isotopic transitional’...Columbia, Canada V7S 3J1 Guaniamo Mining Company, Centro Gerencial Mohedano, Office 9D, La Castellana, Caracas...Caracas, Venezuela Received 27 June 2003; accepted 17 February 2004 Available online 17 July 2004 Abstract...Abstract In Venezuela, kimberlites have so far only been found in the Guaniamo region, where they occur as...emplacement age of the Guaniamo kimberlites is 712 F 6 Ma, i.e., Neoproterozoic. The Guaniamo kimberlites contain | | | Journal (article/letter/editorial) | pyrochlore-group minerals from the Guaniamo kimberlites, Venezuela Victor V. Sharygin a,⁎, Nikolai V....Novosibirsk, Russia Guaniamo Mining Company, Centro Gerencial Mohedano, Office 9D, La Castellana, Caracas...Caracas, Venezuela a r t i c l e i n f o Article history: Received 23 September 2008 Accepted 28 March...Keywords: Pyrochlore Betafite Perovskite Kimberlite Carbonatite Venezuela a b s t r a c t Oscillatory-zoned...minerals are found in the La Ceniza diamondiferous kimberlites, Guaniamo region, Venezuela. This is the first | | | Journal (article/letter/editorial) | peridotitic diamonds sampled by the Roberts Victor kimberlite tapped locally distinct mantle sources of carbon...the main Orapa kimberlite. Diamonds and xenoliths from the mine at the Orapa kimberlite have been extensively...4 5 6 18O /‰ 8 9 10 11 8 9 10 11 /‰ Guaniamo Schulze et al. 2003, 2004 2 3 7 18O Finsch...garnet inclusions in diamond from the Finsch kimberlite. (F) Oxygen isotope ratios of garnet and coesite...coesite inclusions in diamond from Guaniamo. Solid tie lines between two garnets link multiple analyses | | Sobolev, N. V., Schertl, H.-P., Valley, J. W., Page, F. Z., Kita, N. T., Spicuzza, M. J., Neuser, R. D., Logvinova, A. M. (2011) Oxygen isotope variations of garnets and clinopyroxenes in a layered diamondiferous calcsilicate rock from Kokchetav Massif, Kazakhstan: a window into the geochemical nature of deeply subducted UHPM rocks. Contributions to Mineralogy and Petrology, 162 (5) 1079-1092 doi:10.1007/s00410-011-0641-4 | Journal (article/letter/editorial) | this study. Coesite (Katayama et al. 2002) and magnesite inclusions are found in zircons (Shatsky et al...Operating conditions were 14 keV beam energy and *9 lA/mm2 current beam density. For more details, see Neuser...fluorination data of garnet xenocrysts (4) from Venezuela kimberlites (Schulze et al. 2003) and laser fluorination...isotope variations in Cr-poor megacrysts from kimberlite. Geochim Cosmoch Acta 65:4375–4384 Schulze DJ...peridotitic garnet xenocrysts from the La Ceniza kimberlite, Guaniamo, Venezuela. Intern Geol Rev 45:968–975 1091 | | Wang, Zhengrong, Bucholz, Claire, Skinner, Brian, Shimizu, Nobumichi, Eiler, John (2011) Oxygen isotope constraints on the origin of high-Cr garnets from kimberlites. Earth and Planetary Science Letters, 312 (3) 337-347 doi:10.1016/j.epsl.2011.09.061 | Journal (article/letter/editorial) | Editor R.W. Carlson Keywords: garnet peridotite kimberlite oxygen isotope sub-calcic garnet metasomatism...Introduction Oxygen isotope compositions of garnets from kimberlite have been extensively studied. E-type garnets...standards were interspersed with measurements of kimberlite minerals. Results for standards are as follows:...for the generation of high-Cr garnet in P-type kimberlite. This component could be fluid and/or melt penetrating...higher than the EMOG buffer with a C\H\O fluid and magnesite present, DCr garnet/melt can be as high as 70–100 |
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