http://marsrovers.jpl.nasa.gov/gallery/all/1/n/013/1N129338548EFF0300P1652L0M1.JPG

Does that look to you like sedimentary or volcanic deposit? How would one tell the difference?

Sedimentary rock has layers, but so can volcanic rock. Sedimentary rock layers tend to be more unevenly spaced in height than volcanic deposits but I don't know what to make of the layers in this picture. I see some even layers and some uneven. I see what I think looks like volcanic rock (there's a rock with a seem running through it) and chalky white rock. I know what that would imply!

Before Nasa gives us their conclusions, anyone want to take the scoop?

I cant even see if thats the outer edge of an outcrop, or a jumble of rocks. I would want to see elemental and crystallographic ananlysis before i could say if it was sedimentary or volcanic. It looks like its been abraded by something, or else damaged over a long period of time by freezing and thawing.

It looks like it was a large continuous body of rock at one time. I think the broken appearance indicates the physical and chemical destruction of some of the rock over time.

Sedimentary or volcanic? Hard to say. Personally I think it's volcanic or even metorite impact related.

There are some layered volcanic rocks. Rhyolite is a common layered volcanic rock. Basically the volcano erupts and spits out a ton of debris. The particles settle out of the air at different rates based on their size. The result is a layered rock that is sedimentary in appearance but made of up volcanic ejecta.

The texture of the hematite and the inclusion of other accesory minerals will be part of what helps answer your original question.

It's a great pity you suspect it is volcanic. We were all hoping it would indicate presence of water sometime in the history of that region.

I think NASA is hoping it's a sign of water too. It's why they landed these two rovers where they did. My point is that just because we WANT to see evidence of water doesn't mean we WILL see evidence of water.

Don't you see the clue? Right in the middle, small rock to the left .... "Crystal Springs Pure Martian Water"

I'm just an amature but it looks alot like dolomite. It does definetly have striations...ice age possibly....I look forward to you all to educate me on this.

I've just heard that it was bedrock.

More here than meets the eye !

When I get home from work and off this LCD I will try to elaborate.

Candide how did your last post get locked so quickly?

This is thee worst of all forums I have been to .. when it comes to scientific evaluations of any subjects that even touches on "the NASA is full of crap theory"

Definitely

Chunky, you've convinced me! There ARE fire hydrants on Mars! I knew it! Now if fluid can only find those snakes ;) lol

Of course there are hydrants. The snakes needed water to put out the fires created when weapons of war created the crater chains.

It all makes sense! That is where all the machinery rocks are from. War! lol

Question is: Is that an actual fire hydrant? Or did the Martians evolve in such a different path that they happen to LOOK like hydrants?

I just went out to the street and kicked the fire hydrant in front of my house. I can't be positive, but I swear I think it grunted when I kicked it. :eek:

I'm going to wear my tinfoil hat for the rest of the day, just in case.

Chunky and 15, in an effort to get this thread back on point and avoid a warning from the moderator (see: Magnetic Reversals thread), may I talk a bit about volcanism?

The latest pictures from Opportunity seem to indicate (to me anyway) a volcanic origin for the hematite. However, the texture looks like the texture you see when lava erupts under water. So Candide, we may have volcanism and get water too?

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040209a/1M129515692EFF0312P2939M2M1_mi_RobtE_full-B016R1_br.jpg

Link won't open. Check it please.

Pillow lava perhaps? Or maybe it was sedimentary rock that was introduced to high heat from an impact. That would explain the pebbles a bit. If superheated material was thrown into the air, it would have formed droplets that would have cooled very quickly while airborn. Those would have rained over an area. So if they find those only within the crater and around it, it would seem to me at least the it was either an impact or maybe volcanic activity underwater.

Edit: Let me rephrase. It could have been pillow lava that was hit with an impact to form the spherical pebbles or maybe if WAS sedimentary that was affected by the impact to look like that.

From other reports I've read it's the worse kept secret that mars has had running water and still has water on its surface - note the topography carved with river channels, and ice in polar regions etc. The European Mars Express orbitor team intends to estimate the volume of water left on the planet - they think there's water. The question is whether we've been lucky enough to land in a spot where we see evidence in the rocks too and what those rocks suggest about chances of life. Not sure if volcanic rocks would suggest anything either way on the latter question.

These are all interesting ideas, thank you. Can't wait until we get Nasa's verdict after the grinding tests they're going to do.

Why don't they land some explorers on the polar caps?

Surely there must be some water ice with or under that frozen carbon dioxide?

Polar Wanderer was one of the Mars crafts that was lost in 1999 due to a software glitch that made it fall out of the sky a bit faster than it was designed. Too bad. If we had data from Wanderer, we could refute the Euros who insist they've seen signs of liquid water at the poles.

I think the snakes that Fluid1959 has reported seeing in photos may actually be remnants of Ordovician age firehoses?

I have no doubt there is water at the poles. But as ice and intermixed with dry ice. Given a chance to escape it would sublimate and be less useful water vapor to future travelers.

How do you expect us to tell with this image? Find us a microscopic image of the same outcrop, which they have, and we'll give you a correct answer without speculation.

And Mars' rocks are basaltic, not granitic, so Princess, rhyolites are not very important to us at the time being.

And Mars' rocks are basaltic, not granitic, so Princess, rhyolites are not very important to us at the time being.
So you are postulating no fractional crystalisation whatsoever? No magmatic differentiation of any kind? A bit extreme? No?