[meteorite-list] Stan's NWA 2965 EL6/7

[David Weir]

Hello List,

After reading the AGU abstract posted by Greg, I certainly think the 
investigators have made huge progress in arriving at a consensus on the 
correct classification of this 1+ ton mass, previously described as an 
igneous aubrite, a highly equilibrated EL6/7, and an En-metachondrite, 
and, after analyzing the NWA 2828 stone, was considered to represent 
multiple meteorite falls. The AGU abstract adequately and interesting 
explains the characteristics in light of it being an EL3 fossil 
meteorite with primary, unequilibrated components, with a very sparse 
abundance of chondrules.

However, with less than 5 vol% chondrules, how can it be related to the 
typical EL chondrites with much higher chondrule percentages of 60-80 
vol%? This is still a pretty strange object. At the very least I would 
think it should be given an EL3-Anom label. After all, Maralinga was 
primarily given its anomalous label because of its higher than normal 
chondrule/matrix ratio, although I think its 50 vol% compared to the 
typical 15 vol% of typical CKs pales by comparison. The only chondrite 
with less than 5 vol% is the CI group (much less than 1 vol%). How did 
chondrules become sorted out of the matrix in this one? I await more 
scientific insights on this.

A public thanks to those owners of the various masses of this fossil 
meteorite who donated material for its in-depth study.

David