[X] My Assistant

[Guest_Richard Trigaux_*]

On sol 886 Oppy's microscopic imager takes shots of a new type of stone previously unseen in Meridiani planum. This place was already shot on sol 885 by the Panoramic Camera, showing a patch of soil looking like gravel.


These stones are clear, chalky looking, with angulous fractures, but slighty rounded as if transported for a while in a river bed. They also show some hollows or veins in some places. In the background there are small more or less rounded stones evoking the smaller blueberries already seen in the beginning.


So I wonder what these stones could be. The most conservative explanation would be that they are freshly broken jarosite, submitted to a bit of eolian erosion. But other explanations are possible. We shall remain in the expectative until some analysis is done.

[Bill Harris]

Can you point out specific rock in the MI images? I see some pieces of broken evaporite, but not what you describe.

--Bill

[Guest_Richard Trigaux_*]

Can you point out specific rock in the MI images? I see some pieces of broken evaporite, but not what you describe.

--Bill

This rock (the big one)


Yes, it could be evaporites, but on other images they appear dark, which evaporites never do. (This is a context view of the MI images, see the same image in a similar wavelenght than the MI images)


even if it is evaporites, it is rather unusual to find them under the form of freshly brocken small blocks. Beagle crater must be very young, even more than Fram crater.

With my opinion there is a kind or erosion of the evaporites. They would lose their chemical binding water, and this lefts only some powdery stuff (try to heat some plain gypsum crystal, it turns to powdery plaster). So any kind of block seems to "evaporate" (which is usualy interpreted as a wind erosion). So on young craters, we find all sizes of blocks, on medium craters only big bloks, and in old craters the king of flat "pavement" seen on Endurance rim.

[dilo]

Are we talking of this strange, blue/gray rock pictured on Sol887 by PanCam (L456 filters)?

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