Salty Mud Polygons In The Andes Match Those On Mars
High desert salt flats have identical polygons to those on Mars
When searching for mud polygon images, I came across these images located on a page by Chris Goulet, who biked through the Andes Mountains. It shows how the drying mud, when in a briny or very salty environment, forms irregular polygons with the edges prominent.
His page documenting his bike trip can be found here at this link.
| When salty mud dries out,
it creates polygons that are a little different from non-salty mud
polygons. The difference in that the edges tend to curl upward or
form a lip, indicating not only the presences of salts but also that
subsurface water is present through the drying process.
This image clearly reveals the mud polygons and their margins. To see a full -sized image, click here. Copyright, Chris Goulet. Image used with permission. |
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| This is a typical view of
the mud polygons in Ubehebe, in Death Valley.
Image Copyright 2001, Lee Watson (used without permission) |
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| Here is another view of the mud
polygons. This is a very salty area and is associated with a dried
salt lakebed.
The original image can be seen here. Image Copyright, Emma C. Rainforth of Ramapo College (used without permission) Her page link is here. |
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| Now here is an image made
by Opportunity's left panoramic camera on Sol 208. See the distinct
raised lips on the polygons? This can only form when mud dries under
the following conditions-
a) very salty or briny mud b) subsurface water still welling up from beneath This is proof that when these geological features formed, they were in a briny environment and that the ground was wet from beneath for a period of time after the surface dried. The original image is here at the NASA/JPL website. Click here or click the image for a full sized view.
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If you look at the stereo image, it proves that the lips of the polygons are raised. You can view the full color cross-eyed version here. In short, these formations on Mars were made in the presence of very salty water and furthermore, underground water continued to be present after the polygons formed and kept the underlying layer of soil wet for some time.
