QUOTE (Indian3000 @ Dec 19 2006, 03:44 PM)
I leave my marathon of creation of all spirit's pano for my HiRouteMap to make small pan of sol 1032
Mister Indian3000, that was beautiful. I think you have managed to capture technical perfection and lovely artistic impression in the same grayscale image. I love it.
QUOTE (alan @ Dec 19 2006, 07:22 PM)
These remind me of a feature in Endurance Crater. Could this be a "bathtub ring"
It could well be one appearance of it, but don't think of the BTR as a chiseled line in the rock. If I have the model correctly imagined, it is more like the average highest reach of the the ancient water table. If the groundwater did not dwell for long above a certain level, there will probably not be very many concretions formed there. Probably at the same time the concretions are forming in the ground water saturated environment, other minerals may be dissolving and precipitating elsewhere, creating other changes in the textures of the rock. If the water remains near a level long enough, it can leave an imprint of its presence. But other processes can create an abrupt change such as the one you pointed out. That seems to be a contact worthy of further study.
The geochemistry of iron during the formative years of the planets has long been been one of my favorite subjects. That element seems to have been quite abundant on/in the inner planets at the same time certain planets' atmospheres evolved from chemically reducing environments to more oxidizing ones, thus changing the chemical behavior of iron. Seeing such apparently ancient rocks with clues to that story, delivered to us by a space-faring robot created by our species, leaves me speechless...