Victoria Crater (APOD 2 Oct 2006)

melaleuca_52 · Post by **melaleuca_52** » Wed Oct 04, 2006 7:16 am

I am curious that something appears to have ridden a trike around the inner lip of the crater, possibly starting over on the far left. Any comments, anyone?

harry · Post by **harry** » Wed Oct 04, 2006 8:19 am

Hello Melaleuca_52
Welcome to the site.

Do you think the robot made those marks.

Where is Aichip, he can explain things on Mars.

aichip · Post by **aichip** » Wed Oct 04, 2006 11:46 am

This is the same sort of markings that appear on many of the dunes. It is caused by the melting of water ice in the sand, in my estimation.

When ice crystals freeze in the soil, they exclude the salts and form nearly pure water ice. This ice can remain for a while when it is colder and then, when summer arrives and the heat of the Sun penetrates the soil, it will melt the ice. This means that portions of the soil are more or less salty, having been washed with fresh water from the melting ice crystals.

If you examine many of the past images of the dunes in the region, you will see where the same linear bands appear. The layering is uniform because the thickness of the soil layer is uniform. This is how far the heat needed to melt the ice has penetrated. The uniformity is due to that heat penetration.

This is just my theory, but based on my findings and observations I believe it to be reasonable.

craterchains · Post by **craterchains** » Wed Oct 04, 2006 2:09 pm

It reminds me more of past standing water levels of a small lake receding.

Norval

Dr. Skeptic · Post by **Dr. Skeptic** » Thu Oct 05, 2006 12:15 am

It is layered sand of various colors and textures deposited from sand storms of different magnitude and direction then eroding back to reveal the geological differences in the sand carried from storm to storm.

Wadsworth · Post by **Wadsworth** » Thu Oct 05, 2006 2:34 am

Dr. Skeptic wrote:It is layered sand of various colors and textures deposited from sand storms of different magnitude and direction then eroding back to reveal the geological differences in the sand carried from storm to storm.

He says so matter of factly..

I think that is a quite possible theory, but one would expect more than just three evenly spaced rings. Especially on the section that is flattened out. But then one could argue, there is just as much chance of having three rings as there is of having 30.
I suppose the alleged sand deposits would have happened before the meteorite strike.

Wow, I just looked at the wikipedia 3D pics. They show the size of the creator much better.

Dr. Skeptic · Post by **Dr. Skeptic** » Thu Oct 05, 2006 12:33 pm

If you don't trust me contact Steve Squyres or http://athena1.cornell.edu/reference/contact.html

aichip · Post by **aichip** » Thu Oct 05, 2006 5:16 pm

This is not a matter of trust. What Steven Squyres is expressing is an opinion, just as what I expressed was an opinion. Considering how far off the mark their information has been in certain releases, I tend to trust my opinions a bit more fully.

The point is that both are opinions, but I make that certain while Squyres and company insist they are correct without strong supporting evidence. If he is correct, then why do the same layers appear in the dunes? It is not possible for the dunes to form these identical layers in the manner he purports. Therefore, his opinion violates the observational evidence.

On the other hand, dunes can easily conduct heat at a known and predictable rate, resulting in the melting of ice contained within and resulting in the layered structures that we see. In other words, my simple theory explains both observations with equal ease.

Dr. Skeptic · Post by **Dr. Skeptic** » Thu Oct 05, 2006 8:28 pm

H2O seepage is evident from subterranean sources, the rim of the crater is topographic. if the layers were near the floor of the crater you theory may have a chance - how many million photos would you like showing concentric layering of sand dunes?

BMAONE23 · Post by **BMAONE23** » Fri Oct 06, 2006 7:35 pm

http://marsrovers.jpl.nasa.gov/gallery/ ... 1006a.html

Here is the latest from Opportunity

http://marsrovers.jpl.nasa.gov/gallery/ ... -annot.jpg

interesting that we can see the rover now

aichip · Post by **aichip** » Sat Oct 07, 2006 2:16 pm

Dr. Skeptic wrote:

if the layers were near the floor of the crater you theory may have a chance - how many million photos would you like showing concentric layering of sand dunes?

What is your point? A NASA scientist has already theorized that up to half the sand dunes' content could be water ice crystals. Why would they preferentially melt at the floor and not at the rim? The layered dunes certainly appear to show this behavior.

As for layered dunes, there are thousand of images in the MER data already. I don't think a few more will make much difference.

Dr. Skeptic · Post by **Dr. Skeptic** » Sat Oct 07, 2006 4:47 pm

Deposit striations will be uniform, ice melt is dependent on solar energy, (incident angle, exposure duration) producing lesser defined horizontal striations in proportion to exposure.

aichip · Post by **aichip** » Mon Oct 09, 2006 5:01 am

So what you are saying is that in the dunes, the sand was deposited in layers first, and then some of it blew away to leave layers? In other words, that these are not dunes, but hills of sand left from something eroding other sand away? That is not logical.

The dunes formed first, the layers formed afterwards. Think about it. Really.

harry · Post by **harry** » Mon Oct 09, 2006 8:14 am

Hello All

Aichip's logic sounds great and possible and yet why not what Dr Skeptic says. Can we have a combination effect or is it one or the other.

Dr. Skeptic · Post by **Dr. Skeptic** » Mon Oct 09, 2006 11:48 am

aichip wrote:So what you are saying is that in the dunes, the sand was deposited in layers first, and then some of it blew away to leave layers? In other words, that these are not dunes, but hills of sand left from something eroding other sand away? That is not logical.

The dunes formed first, the layers formed afterwards. Think about it. Really.

What's not logical?

Deposit, then erosion - nothing unique about that.

aichip · Post by **aichip** » Wed Oct 18, 2006 8:26 am

Sorry for the absence for a few days, under the weather.

Dr. Skeptic wrote:

What's not logical?

You seem to have overlooked a very simple, glaring fact about this. If the layering was present before the formation of the dunes, every dune would have the same layering at the same profile or height. This is not the case.

Dunes of different heights have the same layering, reaching the same heights respective to the dunes and not the bedrock - therefore the layering came after the dune formation. It cannot be otherwise. For your theory to be correct, the layering would have to proceed for however many years during which dunes would not form, and then suddenly, the sand would somehow etch away to leave what looks like dunes in every respect but would not be dunes.

Dunes march across the landscape and cannot carry layering with them, nor can they be formed in the conditions that would deposit thick layers of sand which would be changing over many thousands of years needed to create those layers. You are proposing that for ages, sand layering is the major force, yet one day, something changes and then layers no longer form but somehow the wind selectively removes material to make what looks like dunes but what is not dunes. And, that those stationary mounds of sand would somehow stand, containing layers, while some force (which could not be wind) removes much of the sand without touching the "dunes".

How do you propose that this happens without disturbing the layers of spherules? Notice that through all of this, the spherules are still on top of the soil. Have you actually noticed that?

Their presence on the surface and not below the surface proves that there is waer ice in the dunes. Really do think about this. The process is called frost heave. And when you realize that the spherules are on the surface only and not buried in the sand (as proven by numerous trenches dug by the rovers and the heatshield) then you see that water and water ice are present. There is no other explanation.

When that realization hits you, you then must admit that the heat from sunlight could diffuse through the upper thickness of the soil and melt some of those ice crystals and cause the layering very easily. And you then see that the layering is conformal to the dunes based on depth and thickness only. Now you can see a simple and plausible mechanism for these to be actual dunes, a common phenomenon, and to also support layering in exactly the manner we see.

One simple datum, the presence of water ice in the soil, exactly explains what we see without resorting to a complex theory that has thousands of years of deposition of one type of sand, then another, then back to the first, then the second, and so on, then suddenly an episode of some force removing sand to form what looks like dunes but cannot be because they must be stationary to support those layers.

Dr. Skeptic · Post by **Dr. Skeptic** » Wed Oct 18, 2006 12:39 pm

I think you misinterpred my point, the dunes were deposited post impact in different but relatively uniform strata, then non-linear erosion exposed the differences in the dune's layers as the age rings of a tree.

aichip · Post by **aichip** » Wed Oct 18, 2006 1:30 pm

No, actually I understand your point quite well. You are basically saying the layers formed first and that consequently these are not dunes. I am saying that these are dunes and that the layers formed after the dunes blew in and are still forming today.

The difference is that you claim the layers are from deposition of differing materials and I claim that the sand is uniform but heating from the sun melts ice inside the dunes to create the layers.

BMAONE23 · Post by **BMAONE23** » Wed Oct 18, 2006 5:08 pm

Two things could solve this. First, if the rover can easily dig a trench through the strata linear feature then they are probably dunes (now anyway). Second, if the features are hard pack and only exist on the eastrn and western slopes of the crater then they could have been exposed by wind blown sand type erosion of stratified layers. If you notice near the north end of the crater, the dark sand material is being blown out of the crater and carried of towards the NNW by prevailing winds. This would suggest that the predominant winds come from the south - southeast on the plains but tend to orient towards north within the crater.

Dr. Skeptic · Post by **Dr. Skeptic** » Thu Oct 19, 2006 2:26 am

It could be a combination of both if the crater wasn't within the 10% most arid locations on the planet and at a lower elevation. Active evidence of subterrainial melt and erosion is usually seen at crater and faults at depths over 50 meters - most of the surface H2O through out the Meridiani Planum has evaporated over the eons. I don't have time to look it up but I believe the surface H2O at Victoria Crater is less than .0001% - not enough to form any type of visual ice crystallization. Deposits of different colored materials is the only logical answer. I have only taught one terrestrial geology class so maybe a planetary geologist would be willing to set the record straight.

BMAONE23 · Post by **BMAONE23** » Thu Oct 19, 2006 2:33 am

Given the current view of Victoria http://marsrovers.jpl.nasa.gov/gallery/ ... not_br.jpg you can see thet the current prevailing winds are blowing the localized dark soil to the north. Perhaps over time the winds have changed directions again and again causing the alternating layering of lighter surface (Planes) soils and darker crater soils.

aichip · Post by **aichip** » Thu Oct 19, 2006 10:20 pm

Dr. Skeptic wrote:

I don't have time to look it up but I believe the surface H2O at Victoria Crater is less than .0001% - not enough to form any type of visual ice crystallization.

In other words, if I could show you strong evidence of present day water in significant quantities, might you be willing to concede that the layering is from ice crystals?

You see, this is one of the most important points I have tried to express and I have a huge body of evidence that liquid water is presently acting in the region and that it has been present all along. That in fact we are seeing present day erosion driven heavily by water and not as much by wind.

I can show that erosion rates are comparable to Earth right now, that erosion is presently erasing features and that therefore the features are constantly being renewed (or we could not se them) and that the erosion is causing the formation of the stems and is also causing other very visible signs that wind canot create.

Victoria already has shown the presence of fumaroles very clearly (which I can also demonstrate) and that they are active as we speak. If I can demonstrate this to you, are you willing to admit that there must be significant water in the region now?

Dr. Skeptic · Post by **Dr. Skeptic** » Fri Oct 20, 2006 1:34 am

Not only would you need to prove the existence of a significant amount of H2O present in the sand, you would also need to explain the uniform layering of the H20 in the sand, explain why the H2O is not evaporating, why the capillary effect isn't making the H2O layers bleed into other layers, why the different layers seen to erode at the same rate (the presents of ice and/or H2O will reduce the erosion rate of sand), why the layers are uniform independent of solar angle, and I can come up with more problems with your theory if you'd like.

aichip · Post by **aichip** » Sat Oct 21, 2006 6:51 pm

Dr. Skeptic wrote:

Not only would you need to prove the existence of a significant amount of H2O present in the sand

If the oceans of the world and all the lakes were removed at one stroke, it would not eliminate the underground sources that exist. Numerous springs, geysers, and volcanic vents still would be here, spouting water as they do. Mars did not lose its water entirely, it still has springs and geysers as well as some volcanic activity.

Is it unreasonable to accept that a planet with oceans would also have a hydrologic cycle? We already know of the glaciers from the frozen sea on the equator, the ice in craters, and the ice in the polar caps. Los Alamos produced a beautiful map of water distribution recently and even Viking showed the atmosphere to remain near 100% relative humidity nearly all the time.

So, as the axial tilt of the planet changes, it goes through the equivalent of ice ages, and as dust covers the glacier fields it protects a great deal of the ice from sublimation. Also, the extremely large quantities of salts in the soil act as an antifreeze, allowing the resulting brine to remain liquid at a much wider range than for fresh water. Here are some images of present day geysers on Mars from my site, and all have links back to the original NASA/JPL images on their site.

Sol 122 geyser from Opportunity: http://xenotechresearch.com/geyop122.htm
You can see the spherules have been blown back from the slot, and there is even a second smaller slot in the background above it. Clearly mud has run from the slot and material has been moved by whatever fluid emerged.

One frame from the large geyser field above Endurance Crater, Sol 114:
http://xenotechresearch.com/o114clr5.jpg

All along the left edge, and along the top left edge, we can see where the fluid emerged from under the rock slabs. Again, this soil is damp and cohesive. Desiccated sand will not cling together like this soil does.

Two geysers showing mud flow, also from Sol 114, Endurance Crater: http://xenotechresearch.com/o114clrc.jpg

Again, distinctive flow patterns of mud. Sand cannot hold this form without the presence of a liquid to help stick the granules together. There are many more images of geysers above Endurance Crater, brought together on this page: http://xenotechresearch.com/imo114.htm

Can we get more solid evidence than these images? Yes.

http://xenotechresearch.com/marsmud.htm Look closely at the top image. Water flow has created the patterns you see trailing behind the spherules. The "rock" is little more than sand and gypsum and salt. And, the next two images show on Sol 123 that the instrumentation arm was pressed against the mud and it bulged. The highly reflective nature of the soil is because it is wet. The bulge is not possible with desiccated sand. What fluid do you suppose might be holding the soil together so aggressively?

What about a picture of actual liquid water on the soil? Sure, no problem. This is a false color stereo image showing exactly that. http://xenotechresearch.com/O146stc2.jpg

You can see the trail from the end of an eruption as the geyser lost pressure and the water trailed away. The water is still present as a long, sinuous trail that breaks up into droplet trails. You must admit that something has landed on the soil there. the absorption from the infrared images closely match the absorption for liquid water. Go ahead and look at the radiometrically corrected images and see for yourself.

Here is a picture of another geyser just above Endurance Crater complete with a mud flow. Wind cannot create the pattern of flow and terracing you can see in the left bottom of the image.

http://xenotechresearch.com/o118clr1.jpg

I can also supply the images in stereo so you can confirm for yourself the three dimensional nature of these images, and these are just a scratch on the surface. I have sorted, processed and categorized hundreds of them. A child can see the flow patterns in the soil, and the fact that this cannot be dry sand.

In fact, let me provide you with a stereo image of the geyser slot itself that produced the water that made this flow. You can look right down into it. Wind does not make this sort of feature. Something emerged from under the rock slab and made this slot.

http://xenotechresearch.com/Vent3d2.jpg

Here is a full color stereo image set of a geyser from Sol 614, Opportunity.
http://www.xenotechresearch.com/marsgey6.htm

How do I know that something is coming from under the slabs? Easy. Cover the slabs with sand and their margins end up clean. Something emerges from beneath to clean just the outlines, as seen in this image from Sol 541:
http://marsrovers.jpl.nasa.gov/gallery/ ... 07L0M1.JPG
Look left of center at the slabs. Did wind selectively blow off just the edges? No. Steam or water emerging from beneath did it.

Finally (because I really don't have the time or inclination to post hundreds of images and explanations) I will wrap this up with spray zone from a geyser just inside Endurance Crater.
http://marsrovers.jpl.nasa.gov/gallery/ ... 94L2M1.JPG
The water has sprayed up and onto the soil, creating a bowl shaped washout area. If you want full stereo and color (plus the image containing both geyser and spray area) along with full color and stereo images of the geyser itself, I will gladly supply them.

Next point.

Dr. Skeptic wrote:

you would also need to explain the uniform layering of the H20 in the sand

The water is not uniform, it is throughout the soil. The heating is episodic and occurs over the seasons. As heat diffuses into the soil, it melts ice crystals and forms the layered appearance. Note that the layers are conformal with the dunes- start from the top and go down and they match the dune tops.

http://marsrovers.jpl.nasa.gov/gallery/ ... 75L0M1.JPG

Note how as the dune height changes, the layer height matches them. If layering happened first, it would conform to the bedrock layer, but it does not. How about this one?

http://marsrovers.jpl.nasa.gov/gallery/ ... 75L0M1.JPG
You will notice two interesting things. One, the layering is preferentially on the right sides of the dunes! Two, the layering is different on one side from the other. This means that the layers formed after the dunes. Do you know why they layer this way? This is very simple. Any experience with soil hydrology will tell you.

Wind moves through the soil and drives moisture to the lee side. Wind pressure forces the water that is liquid to migrate away from the wind. This is a known factor and here we see proof of it on Mars. Sand is porous and wind can in fact exert a large differential pressure on a sand dune. Here it is in spades.

Next point.

Dr. Skeptic wrote:

explain why the H2O is not evaporating

No, that has already been explained by others far more qualified and many times. It does not evaporate because the relative humidity is nearly 100%. The air is already loaded with as much moisture as it can carry, and even with advection there cannot be any more evaporation. Just as you can only dissolve so much sugar in water, you can also only carry so much moisture in a mass of air. Afterwards, no more sugar will dissolve, and no more water will evaporate.

http://dailyheadlines.uark.edu/5717.htm

Dr. Gil Levin has also done the experiments and shown the same results. The rate of evaporation is between 0.8 and 1.1 millimeters per hour under Mars temperatures and pressures. In the soil, where the surface of the granules prevents evaporation and there is a large quantity of salts, the rates are far, far lower. If you continue to insist that liquid water cannot exist on Mars, then you are just plain wrong. Sorry.

Dr. Skeptic wrote:

why the capillary effect isn't making the H2O layers bleed into other layers

It does. Note the different layering in the above NASA/JPL image showing the differences from front to back of the dune. Broad stripes of melted water diffusing into other zones, limited by freezing temperatures and heating, produces the stripes.

Dr. Skeptic wrote:

why the different layers seen to erode at the same rate

How can you tell what the rate of erosion is? The layers form in the dunes, sometimes the dunes blow around and new layers form. This is a dynamic system, not a static snapshot.

Dr. Skeptic wrote:

why the layers are uniform independent of solar angle

Look at how heat flows through a triangular cross section. Heat takes time to travel through materials, and when the ice does melt, the latent heat is still present in the water as it is blown through the soil or as it seeps into the dune. Sun angle can change significantly while the heat remains soaking into the sand.

Dr. Skeptic wrote:

and I can come up with more problems with your theory if you'd like

...and I can answer them. Gladly.

Starship Asterisk*

Victoria Crater (APOD 2 Oct 2006)

Victoria Crater (APOD 2 Oct 2006)

Mystery Martian tricycle

Trust?

Why the crater floor?

Deposit striations and dunes

Re: Deposit striations and dunes

Dune Layering

the point

Lack of water

piecemeal examination of points