[meteorite-list] Sedimentary Martian Meteorites

From: Walter Branch <waltbranch_at_meteoritecentral.com>
Date: Mon, 21 Mar 2011 22:56:44 -0400
Message-ID: <008901cbe83c$c83a8030$0402a8c0_at_Desktop>

Hello Steve, Carl and List,

Thanks very much for the comments.

I am at a distinct disadvantage, not having a background in geology so
please bear with me.

I understand exothermic processes but...

The oldest sedimentary rocks are found in various places such as Greenland,
Hudson Bay in northern Quebec, Western Australia, etc. These rocks are
billions of years old, yet they are still recognized as sedimentary rocks.
Why? Should they not have disappeared long ago? Would you say these rocks
were never exposed to heat, water or weathering?

I would think that traveling through space, where obviously no terrestrial
weathering occurs, potential Martian sedimentary rocks would not undergo
weathering until they landed on Earth which would be on the order of
millions of years ago. Much more recent than the oldest Earth sedimentary
rocks.

It may very well be that the reason we don't have any Martian sedimentary
rocks in our collections (scientific and otherwise) is because they have all
weathered away or at least to the point where we would not recognize them as
being Martian, or even meteoritic, in origin.

Yes, I have looked at Dr. Irving's site.

http://www.imca.cc/mars/martian-meteorites.htm

It's a great site and is on my favorites list but he doesn't speculate as to
why we have no Martian sedimentary rocks, which is what I am most interested
in.


-Walter
Received on Mon 21 Mar 2011 10:56:44 PM PDT