Progressive Alteration of Cm Chondrites: Effects on Refractory Inclusions
نویسنده
چکیده
CM chondrites are aqueously altered rocks that contain ~9 wt.% H2O (indigenous water) [1] bound in phyllosilicates [2-4]; also present in the matrix are serpentinetochilinite intergrowths (PCP), pentlandite, and Ni-bearing pyrrhotite. The extent of alteration varies from meteorite to meteorite. Some CM chondrites contain well-delineated metallic-Fe-Ni-bearing, olivineand pyroxene-rich chondrules; others are rich in phyllosilicates and sulfide and contain chondrule pseudomorphs with no olivine or pyroxene and very little metallic Fe-Ni. There is a broad consensus that CM-chondrite alteration took place on the parent asteroid [2,4,5-10].
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