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Fraser
2005-Jul-07, 06:28 PM
SUMMARY: From space and even on the surface, Mars just looks dry, reddish and rocky as far as the camera can see. But there's actually a pretty complex world of minerals under that surface layer of basalt. By studying the surface of Mars with Mars Global Surveyor and Mars Odyssey, NASA scientists have turned up very interesting surface features which hint at the hidden minerals underneath. This research is published in the latest edition of the Journal Nature.

View full article (http://www.universetoday.com/am/publish/mars_heat_signature.html)

What do you think about this story? Post your comments below.

lswinford
2005-Jul-07, 09:54 PM
In an early geology class I was told that the essential difference between basalts and granites was that basalts were ignious intrusions under water and granite (not metamorphic) was on land. Then I learned there were mafic or felsic magmas, respectively, and the mafic magmas (basalt) were comparatively anemic in silicas. The feldspar/quartz felsic magmas that produced granite therefore had a different chemistry. It was obviously beyond what that first instructor summarized, implying a sea water vs. dry air solidification environment. The remelting story presented is a still different picture and I suspect that his granite was more the metamorphosed variety. Still, there has to be an injection of silicas and aluminum/potassium minerals (feldspars) to fit. So our nice summary still has a lot of missing pieces lurking out of sight.

Frankly, I don't think we have enough down deep data yet, be it stratigraphy or drill cores. Some nice freshly exposed major faulting (those little cracks and rills seem too uniform, too old) or discernable plates would be helpful too.

om@umr.edu
2005-Jul-07, 10:21 PM
Hi, Fraser.

This is an interesting story.

Layering is very common, but many of our conclusions are based on surface observations.

Observations posted on UT earlier today suggest that there is also a complex interior to the Sun's veneer of Hydrogen and Helium.

With kind regards,

Oliver
http://www.umr.edu/~om

damienpaul
2005-Jul-08, 09:50 AM
I totally agree with Iswinford - we need to drill deeper to gain a better understanding of the Martian stratigraphy.



Here we go again, Dr. M. This is about Mars.

om@umr.edu
2005-Jul-08, 10:27 AM
I find this post offensive and a step beyond good taste. I have removed it.

Dr Manuel, if you cannot help but make argumentative, insulting replies, then do not post.

damienpaul
2005-Jul-08, 10:40 AM
I will give an informed postion in the appropriate thread. Also could you answer the questions given to you in the climate change forum.

Back to teh topic: MARS - possibly a silly, yet old question - is it believed that the mineral occurerences are potentially commercial? specifically will it provide enough raw materials for any future base there?

om@umr.edu
2005-Jul-08, 09:58 PM
Originally posted by damienpaul@Jul 8 2005, 10:40 AM
1. Also could you answer the questions given to you in the climate change forum.

2. Back to the topic: MARS
Hi, damienpaul.

1. I found the link to the Climate Change Forum and posted replies to questions there.

2. Perhaps a common mechanism segregates elements into layers - in Mars, in Earth, and in the Sun ?

With kind regards,

Oliver
http://www.umr.edu/~om

Nick4
2005-Jul-27, 02:57 AM
I collect rockes and minerals and i wonder if they will find any new ones.

Nereid
2005-Jul-28, 11:14 PM
So few replies to this story? This is a really fascinating one!! :blink: :D

Mars is complex, geologically speaking! Hooray!!

Years of hard work will be done, almost invisibly, by near-obsessive scientists. They will retire, and die. Decades later some bright young things will read their work, add in some high quality data that's just come down from the Martian equivalent of TRDS, and make a discovery that results in a seminal paper that's cited thousands of times, and changes the history of martian studies forever. Without Christensen and his 'invisible' colleagues, it wouldn't have happened.

Raise your glasses in a toast to the silent achievers!

cran
2005-Aug-01, 01:49 AM
Originally posted by lswinford@Jul 7 2005, 09:54 PM
In an early geology class I was told... So our nice summary still has a lot of missing pieces lurking out of sight.

Frankly, I don't think we have enough down deep data yet, be it stratigraphy or drill cores. Some nice freshly exposed major faulting (those little cracks and rills seem too uniform, too old) or discernable plates would be helpful too.
Hi Iswinford,
you raised a lot of stuff which might better be addressed in another thread along the lines of 'igneous geology/geomorphology', but as damienpaul replied, you were 'spot on' about needing more and deeper data.

Prior to deep drilling, most stratigraphy on Earth was compiled from exposures in major canyons, along uplifted faults, or across the surface of fold belts; I imagine analogous targets will be pursued on Mars.

Don't be too quick to write off the old rills; they are much larger on the ground than the images suggest.

Also, keep in mind that there is a fair amount of loose cover (dust) which may be hiding the most interesting features (the subterranean frozen sea springs immediately to mind).

Tectonic plates on Mars would require plate tectonics on Mars; not a lot of evidence for it, but it's early days - so, who knows?

The range of igneous minerals does suggest a more complex system of vulcanism and fractionation/crystallisation than previously thought; the idea of remelts within volcanic structures is plausible, and would limit the occurrences to volcanic sites.

If, however, dacites and granites prove to be more widespread, then it would suggest an early geologic history for Mars much more similar to the Earth's; then they would start searching for evidence of plate tectonics.

cran
2005-Aug-01, 02:05 AM
Originally posted by damienpaul@Jul 8 2005, 10:40 AM
MARS - possibly a silly, yet old question - is it believed that the mineral occurerences are potentially commercial? specifically will it provide enough raw materials for any future base there?
hi damienpaul,
I don't think they are silly questions; as for their age - who cares?

It's too early to say if the mineral occurrences are commercially viable; commercial viability depends upon the extent, grade, and ease of access to mine and process the minerals involved, and sufficient demand in a market to sell the ore or processed product.

Making such a determination of a prospect right here on Earth can take up to five years of field and lab studies (and market research), and that does not include the initial exploration time to find the prospect in the first place.

The exploration and surveys on Mars are still at the very first stage, which is similar to a regional surface survey on Earth to locate concentrations of marker minerals.

Enough raw materials for any future base? Based on the observations and mapping conducted so far, the short answer is "yes".

cran
2005-Aug-01, 02:13 AM
Originally posted by Nereid@Jul 28 2005, 11:14 PM
This is a really fascinating one!!

Mars is complex, geologically speaking! Hooray!!

Years of hard work will be done, almost invisibly, by near-obsessive scientists...Without Christensen and his 'invisible' colleagues, it wouldn't have happened.

Raise your glasses in a toast to the silent achievers!
Quite right, Nereid, cheers!