In a message dated 20-May-02 1:54:37 PM Pacific Daylight Time, [EMAIL PROTECTED] writes:
<Since the planets are formed from chondritic asteroids, I don't think you can rule them out just because the meteorite is a chondrite.> So are you proposing that there is remnant chondritic material on earth from its formation 4.5 billion years ago? Although the specifics maybe different Mercury and Venus formed through the same differentiation/core formation process as earth. The probability of remnant chondritic material on Mercury and Venus is about the same as it is for earth. <Since the olivine crystals are only found in an iron matrix, that should be your first big hint. > Could be, except that olivine is found as massive formations of large olivine crystals without an iron matrix, just not in meteorites. One notable location is the San Carlos Apache reservation where unaltered mantle material was erupted to the surface. It is now mined for gem quality olivine, commonly known as peridot. So the question remains if there are olivine crystals 60 to 100 kilometers deep on earth (the depth of the peridot source) why haven't we found meteorites composed of just olivine crystals? There is no currently accepted answer. Somewhere I have some of this mantle material from Kilbourne hole in southern New Mexico. If I can find it I will post a picture tomorrow. Eric Olson http://www.star-bits.com ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
