Hello all, I'm back from the edge you might say. I've been quite ill to say the least, but hopefully now on the road to recovery. I'm glad to be back on the list.
The latest pics from the Spirit are truly awesome. Many of you have hoped and dreamed that many/most of the dark rocks in these pictures are fusion crusted meteorites. Personally, I doubt if many of them are meteorites. To me they look basaltic(extrusive igneous) or gabbro-like(intrusive). I have a fair amount of field experience collecting ancient(1.6 billion) intrusive-magma formed rocks from the gabbro family here in Eastern PA. In particular these rocks in the Mars pictures look like a fine-grained iron rich gabbro called metadiabase. Which is a black/dark green rock that weathers to a rusty brown on the outside here on earth. They fragment into both squarish blocks, and conical/rounded pieces over time. On Mars they probably do not weather as much, thus they remain dark on the exterior, and the winds and dust probably do a good job of rounding off edges over time when exposed. I know that the majority of the Mars meteorites we have recovered on earth are not dark basaltic rocks, but more of a lighter colored rock. Many of you (Norbert and others) have kept me straight on the concept that our Mars meteorites are extrusive basaltic types. But if the rocks on Mars are iron rich (helping to create the Red look), then it is my understanding that they should also be dark rocks, and not what we think of as a Mars basalt(ie: Zagami, etc.). My guess is the rocks in these pictures are chunks of basalt flows or exposed gabbro fragments like metadiabase, and not meteorites. Any opinions to this recovering sicko rockhound are welcome? I'm back...I think. John ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
