Spirit - Still Alive - volume 2 - Page 14

Hort;

I am very interested in the comanche images

Winston

sol 698 ( Dec 20, 2005) L257 false color pan of Comanche:

with a 3D link to an interesting part of the rock.

I wonder exactly what part of the rock looks like carbonate? I think maybe the "whitish" parts. The linked 3D detail has curious whitish "flakes" that do not appear to be part of the rock matrix.

This pan was created from 16 bit Radiometrically corrected data.

Nope, looks like magnesium iron carbonate ( gaspeite ) is dark and greenish - so the whitish flakes are something else again.

Hort;

Thanks!! Very nice, particularly the flakes as seen in 3D. I wonder if the Carbonate was found in that area?

Winston

Those flakes look very similar to the "levitating crusts" or horizontal fins that we saw at Concepcion.

We also saw fins in Endurance crater but they were vertical rather than horizontal and were thought to be caused by water action that hardened the side of a channel and made it more resistant to subsequent wind erosion.

At the "original" size, the area surrounding the flakes looks like it might have been altered by water action; there seems to be a microchannel just under it.

There also seems to be some examples of something that looks like the "interesting rinds" of the Oppy conception crater.

Winston

That seems to be a pretty good call Barsoomer. If the carbonates are hydrothermal deposits from a deeper initial source then they would have created fracture fill similar to the Meridiani process. The fracture fills seem more resistant to erosion and thus the 'fins'. But the 'microchannel' would be a function of eolian erosion. The carbonate wouyldn't be restricted to the fill of course but would probably be more concentrated there.

The Planetary Society has a revealing article on this find.
http://www.planetary.org/blog/article/00002540/

All in all the evidence for a warmer, wetter Mars with non acidic oceans and lakes is becoming most compelling. This would have preceded the laying down of the algonquin layer with the subsequent hydrothermal activity creating the carbonate rich comanche outcrop.

Hmm. Another post that disappeared into the aether.

Hortonheardawho - I don't think they meant gaspeite. Perhaps magnesium carbonate MgCO3 (or even MgCO3.nH2O) and iron carbonate FECO3 as separate precipitations.

Barsoomer - I think that is a pretty good call. The carbonate seems to have originated in a deeper layer laid down and then overlaid by the algonquin (and probably other' layers. Hydrothermal action mobilised the carbonates and would have resulted in fracture fills similar to the Meridiani process. The carbonates would not of course have been limited to fracture fill but it seems that the fill is resistant to erosion (assuming the 'fins' are carbonate rich). But the 'microchannel' would be the result of eolian erosion.

The laying down of an original carbonate deposits and the recent evidence for oceans and lakes makes a compelling case for a warmer wetter Mars with a non acidic environment.

The Planetary Society has a good report on this find.

http://www.planetary.org/blog/article/00002540/

My apologies if my original post appears at some stage making this a duplication.

Soon I think,we will know if we will hear from Spirit again.Ever.

Joe in Texas

Best Map of Mars Ever Made Hits Internet

so who/where/any help appreciated,,,if I could start d/loading please?

"Best Map of Mars Ever Made Hits Internet"

maybe this new release?
http://mars.jpl.nasa.gov/odyssey/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=1022

Thanks MPJ,, I have an empty 250 gigabyte,,,taken from a TV recorder,,,

Maybe now I can soon buy my 'LAST',,,Mars globe,,perhaps this time I may buy an overlay for my first one(or not)...

I Goggled 'The Grand Canyon of Mars'
Below is an excerpt,,(sorry if I offend the
Scholar types on this Forum,,,There is also something know as "beginners")

Paste;
This "Grand Canyon" of Mars is about 2500 miles long and up to 4 miles deep. By comparison, the Earth's Grand Canyon is less than 500 miles long and 1 mile ...

A topography map,,that is to say a 'counter' or' depression' on the Globe would be valuable as well..

Joe in Texas

[link]

Joe in Texas