A NEW R CHONDRITE (NWA 6236) FROM FEZZOU, MOROCCO

Abstract

An R chondrite-like meteorite (NWA 6236) was collected at Fezzou, Morocco (30°58.29'N, 4°56.99'W) in September 2005. Based on petrographical features, mineral chemistry, and oxygen isotope ratios, this meteorite shows characteristics of an R chondrite. This study of our petrographical analysis of NWA 6236 is based on microscopy and EPMA areal compositional mapping,mineral chemistry by EPMA, C, N, S abundances, stable oxygen and carbon isotopes, and the results of cathodoluminescence (CL) and thermoluminescence (TL) measurements. This meteorite (ca. 6 x 3 x 3cm, 145g) with a dark bluishgray fusion crust, exhibits an unbrecciated chondritic texture consisting of various types of chondrules and their fragments embedded in a recrystallized olivine-rich matrix. The chondrules are made up of porphyritic to cryptocrystalline olivine, barred olivine, and porphyritic to granular olivine and pyroxene. The size of chondrules varies from 0.1 mm to 0.9 mm in diameter.