Concentrations of Cr, Co, Ni, Cu, Ga, Ge, As, Sb, W, Re, Ir, Pt and Au of two ungrouped iron meteorites, Grove Mountains (GRV) 98003 from Antarctica and Ujimqin, were measured using instrumental neutron activation analysis. According to the bulk chemistry, GRV 98003 is classified as a member of ⅠAB group, and Ujimqin as a unique one of ⅠAB iron meteorite complex. The elemental abundance pattern and correlation between elements (e.g. Ni-Au, Co-Au, As-Au, W-Au, Cu-Au, Sb-Au) of GRV 98003 are similar with those of NAW 468 (ⅠAB), but significantly depleted in refractoRY siderophile elements (Re, It) and moderate volatile elements (Ga, Ge) relative to the latter. In addition, we reclassify Nantan (Ⅱ-ICD) as a member of ⅠAB main group (MG) and Yongning (ⅠA) as a unique iron meteorite related with ⅠAB iron meteorite complex.
Chemical compositions and cassfication of Grove Mountains (GRV) 98003 and other Chinese iron meteorites
1 Buchward VF (1975): Handbook of lron Meteorites. Univ. Calfornia Press, 14-18.
2 Benedix GK, McCoy TJ, Keil K and Love SG (2000):A petrologic study ofthe ⅠAB iron meteorites: Constraints on the formation of the ⅠAB-Winonaite parent body. Meteorit. Planet. Sci., 35: 11-27. DOI:10.1111/maps.2000.35.issue-S5
3 Choi B, Ouyang X, Wasson JT (1995): Classification and origin of ⅠAB and Ⅲ CD meteorites. Geochim. Cosmochim. Acta., 59: 593-612. DOI:10.1016/0016-7037(94)00384-X
4 Clayton RN and Mayeda TK (1996): Oxygen isotope studies of achondrites. Geochim. Cosmochim. Acta., 60: 1999-2017. DOI:10.1016/0016-7037(96)00074-9
5 Chen J, Liu X, Ju Y et al. (2001): Classification of four meteorites from Grove Mountains, Antarctica(in Chinese). Acta Petrologica Sinica, 17: 314-320.
6 (EI Goresy A (1965): Mineralbestand und Strukturen der Graphit-und Sulfideinschlusse in Eisenmeteoriten. Geochim. Cosmochim. Acta., 29: 1131-1151. DOI:10.1016/0016-7037(65)90116-X
7 Ju Y, Liu X (200): Meteorite collection in the Grove Mountains (in Chinese). Chinese Journal of Polar Research, 12: 137-142.
8 Kelly K and Larimer J (1977): Chemical fractionations in meteorites-Ⅷ: lron meteorites and the cosmochemical history of the metal phase. Geochim. Cosmochim. Acta., 41: 93-111. DOI:10.1016/0016-7037(77)90190-9
9 Rubin A (2002): Disturbing the solar system-Impacts, close encounters, and coming attractions. Princeton University Press, Princeton and Oxford.
10 Rubin AE, Kallemeyn GW and Wasson JT (2002): A ⅠAB-complex iron meteorite containing low-Ca clinopyroxene: Northwest Africa 486 and its relationship to lodranites and formation by impact melting. Geochim. Cosmochim. Acta., 66: 3657-3671. DOI:10.1016/S0016-7037(02)00958-4
11 Wasson JT, Willis J, Wai CM and Kracher A (1980): Origin of iron meteorite groups ⅠAB and ⅢCD. Zeits Naturforsch, 35: 781-795.
12 Wasson JT, Ouyang X, Wang J and Jerde E (1989): Chemical classification of iron meteorites: Ⅺ. Multi-element studies of 38 new irons and the abundance of ungrouped irons from Antarctica. Geochim. Cosmochim. Acta., 53: 735-744.
13 Wasson JT and Richardson JW (2001): Fractionation trend among ⅣA iron meteorites: Contrasts with ⅢABtrends. Geochim. Cosmochim. Acta., 65: 951-970. DOI:10.1016/S0016-7037(00)00597-4
14 Wasson JT and Kallemeyn GW (2002): The ⅠAB iron meteorite complex: A group, five subgroups, numerous grouplet, closely related, mainly formed by crystal segregation in rapidly cooling metals. Geochim. Cosmochim. Acta., 66: 2445-2473. DOI:10.1016/S0016-7037(02)00848-7
15 Wang DD, Malvin DJ, Wasson JT (1995): The study of chemical composition of 35 iron meteorites and its application in taxonomy (in Chinese). Geochimica, 2: 115-122.
16 Wang DD, Malvin DJ, Wasson JT (1983): Chemical classification of some Chinese iron meteorites (in Chinese ). Geochimica, 2: 109-120.
17 Wang DD and Lin YT (2002): Overview of classification of Antarctic meteorites, collected by 15th and 16th Chinese Antarctic research expedition in Grove Mountains (in Chinese). Chinese Journal of Polar Research, 14(4): 250-265.