Hello Mike, I have read a description of Zag that is a little more complex than the interpretation of the H3-6 classification which you attribute to it. I think you are correct in that the present accepted two-number system is not adequate for some breccias.
One source describes Zag as composed of four different lithologies - both light and dark clasts (H5-6) [65 vol%] within a gray clastic matrix (H3-4) [25 vol%], plus dark clasts [10 vol%] and impact-melt-rock clasts [<1 vol%]. I'm not sure how such a petrographic mish-mash would be most accurately represented, especially with only two numbers, but the proper interpretation of H3-6 here would include petrographic types 4 and 5 as well, I think. David ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://six.pairlist.net/mailman/listinfo/meteorite-list
