In Search of
The
Cydonia Face
Page Five
The Karst Connection

Ganges Chasma
NASA 3D Image

This seems to be the closest thing to saying that there is karst topography on Mars.

This
3D image of Ganges Chasma is from the Planetary Photo Journal web site. They have a few/various images of the place, along with related images from the Vallis Marineris region.

Another Image of Ganges Chasma
Larger Image
Ganges
Chasma is part of the Valles Marineris system. The original caption release for this image is interesting. First. it says that the center of this Chasma (valley) has a couple of outcrops or eroded remnants of bright, layered rock. (Note the term, "layered". These Ganges Chasma images, produced by Malin Space Science Systems, came out in 1999 -- long before the December, 2000 media anouncement.) One of them is nearly as high as the outside rims of the valley. The make-up of these structures is not known. Speculations include lake sediments (Lake sediments? Anyone kicking and screaming?), volcanic ash, windblown dust, or that it is similar to the chasma walls.

A brief look at these speculations:
Ash
Deposits: Volcanic ash is carried great distances in the atmosphere and usually deposited in thin layers. If the lighter material were ash, then it most likely is in the chasma walls as well - unless it is much younger.
Windblown
dust: There could be deposits of loess here. Loess is very fine, usually calcareous, windblown silt/dust. Its high porosity and very fine grain size give it the ability to absorb a lot of water. The particles resist separation, and stay together in uniform unstratified blankets. In other words, it does not form layers; and unlike other windblown particles, its cohesive structure enables it the to hold together and stand in steep, massive vertical faces, or cliffs. The main sources of loess are deserts, and glacial floodplains. Loess is found in fertile agricultural soils. Colonize Mars? Terraform? Look for the loess!
Lake
sediments? Well, sure! Similar material to the chasma walls? Sure. Both these things are possible. If it is the same material as the chasma walls, then it somehow eroded, or was impacted differently. Maybe the water left before more erosion could occur. Maybe it is some harder material, not easily eroded, covered at a later time with thick deposits of loess. If it is a more stable material, then this same stuff might be found in the valley walls as well. It could be some kind of xeno deposition, different from the materials around it - totally out of phase with the surrounding geology. Some kind of metamorphism could have occured. Or it could just be an ordinary eroded volcanic neck, or perhaps butte or mesa.
This
this structure could be an incised meander. A river can cut back through a ridge, and create a new stream channel or kind of valley. Water originally flowing on the other side of the ridge will follow this new course. A river flowing over a flat plain naturally forms sinuous loops called meanders. If the flat plain is subsequently elevated by tectonic forces, the river may cut down into its own bed as it follows the course of the original meander. The result is an incised meander.

Look where these arrows are pointing on the larger 3D image.
The Larger Image

The
top arrow is pointing to possible stream channels or some kind of depression. It seems deepest where the little dot is. Is this gouged out or sunken? An enclosed valley perhaps?
The right middle arrow points to what appears to be holes in this narrow portion of the cliffs. Although, there doesn't seems to be any light coming through them. Maybe they are not holes - yet. This could be some form of cavernous weathering. Whatever - they are inconsistent with the rest of the cliff face.
The
left middle arrow points to another oddity in the erosion processes going on here. What caused this part of Ganges Chasma to hollow out, leaving that thin wall-like structure indicated by the middle right arrow? What sort of material occupied this space? Could it be a crater, washed away with time? Could it be an old broken down cavern? That would be consistent with the enclosed valley above it. And that leads to another question. Are all those nearby craters really craters?
The
bottom arrow points to what could be terracing. There doesn't seems to be much evidence of river terracing in this place. So it could be the result of sliding instead of changing water level. Or tectonic uplift of the valley floor, which could lead to incised meanders. This provided, of course, that there is flowing water. On Mars any processes such as this are currently stopped.

Karst?
More significant than the outcrops -
The Original Caption Release for this Image also Says...
"The smooth floor of Ganges Chasma, particularly in the area south and west of the bright stack of layered (there is that word again) material, is a thick, relatively flat sheet of dark, windblown sand. The jumbled troughs and depressions that run from the north side of Ganges Chasma toward the upper right corner of the image were caused by the removal of material beneath the surface, followed by collapse. In other words, these features suggest the presence of a large, partially collapsed cavern beneath the surface north of Ganges Chasma. These features might connect further northward with the Shalbatana Vallis outflow channel, but no one knows for sure."

Shalbatana Vallis is where the image,
fha01538, possible Martian karst terrain, is located!

Dare I predict?

The next big news break from NASA will be about karst topography on Mars.

They are studying it.

"The Cave That Hold Clues to Life on Mars"

Other Related Links
Lechuguilla Cave -- Lechuguilla Cave -- Paleokarst
The Lechuguilla Breccia, an interesting "Earth analog" - what might be found on Mars
FREE Photos of The Lechuguilla Cave -- Beautiful Cave Pictures For Sale


If
this is any kind of proof that karst exists on Mars, then it is likely that karst geology is also present elsewhere on the planet. For instance, Cydonia, or any other place where there might have been groundwater - which is just about everywhere.
Bear
in mind that it really doesn't take large bodies of water, like seas and oceans. All it takes is ground water, and maybe a river system, with lots of limestone or other soluable rocks. And carbon dioxide, which Mars has in abundance. Or sulfuric acid, produced in groundwater by oxygen and hydrogen sulfide gas raising from below.



One example of a karst landscape

The Face

Steve Wingate's enhancement of The Face, with possible karst features

A basin, sinkhole or collapsed cavern would not be an isolated structure. Such things are the result of many interrelated processes. Connect the dots - as a certain radio talk show guest says.


Could it be something like this?

COMING SOON

Closer looks at other parts of the face. Are they karst structures?
- - - -
Natural, Artificial, or Both?

-- Image Credits --

Steve Wingate of Anomalous Images and UFO Files