QUOTE (dvandorn @ Nov 28 2006, 12:22 AM)
I'll also point out that a somewhat similar strata over by Home Plate read out to be quite basaltic, in keeping with the chemistry of the plains basalts. I'd like to think otherwise, but I betcha these "berries" turn out to be basaltic in content, as well.
-the other Doug
If you are talking about the lower, coarser-grained unit at Home Plate, I completely agree with you. Spirit observed this unit with the MI on sols 747 and 750. http://marsrovers.jpl.nasa.gov/gallery/all/spirit_m747.htmlhttp://marsrovers.jpl.nasa.gov/gallery/all/spirit_m750.html
This new layer seems to show more of the spherules, but I would have to guess this rock is closely related to the unit at the base of HP. The geologic context here is very different from that at Meridiani. The resemblance of these spherules to the berry concretions is only superficial. Coincidentally, SS mentioned the spherules in that lower unit recently in the CEPSAR lecture that DeChengst so kindly made available as an avi file. Shortly after 26:20 he said: "...you can sort of convince yourself that they're reminiscent of lapilli, perhaps." Be sure to note that he said "sort of," and "perhaps." Lapilli, or some lapilli-like clasts would fit better into the geologic context of this environment, which is thought to be energetic...explosive volcanism or explosive impacts, or such.