Printable Version of Topic

Posted by: dilo Jan 2 2006, 10:04 PM

On Sol 690, Oppy PanCam captured some beautiful images of the rocks, with radent afternoon illumination giving strong relief to stratifications and 3D structure.
Here a stitch:

I already asked to Malgar to make a photoclinometry on this...

Posted by: malgar Jan 2 2006, 10:28 PM

Here there are my works.
I hope in the future to improve resolution and fidelity.

Posted by: Bob Shaw Jan 3 2006, 01:48 AM

Try some 3-D pairs!

Bob Shaw

Posted by: CosmicRocker Jan 3 2006, 02:34 AM

Wow, malgar. Those are very nice. Which software do you use?

Posted by: jvandriel Jan 3 2006, 07:29 PM

Here is the other one from that same Sol 690.

Taken with the R1 pancam.

jvandriel

Posted by: Nix Jan 3 2006, 07:56 PM

I've been plaing with those images too. The lighting is terrific for small detail.

Nice work guys!

Nico

Posted by: ilbasso Jan 3 2006, 08:49 PM

The one from Sol 690 looks almost like one of those MGS photos of a chasm from orbit!

Posted by: Shaka Jan 3 2006, 08:57 PM

Am I the only one who thinks this came out of a pamphlet on the construction of terraced rice paddies? Why does Ma Nature always seem to get there first?

Well, we seem to have ratted this outcrop at long last. Lets do the analytical thing and then...

BEAT FEET!

Posted by: malgar Jan 3 2006, 10:09 PM

Like a crossed eyes?

Posted by: malgar Jan 3 2006, 10:12 PM

I use a simple script that integrate pixel values row by row and I render the elevation map with GRASS, a GIS program. I must use an heavy low pass filter due strong noise.

Posted by: nprev Jan 4 2006, 12:14 AM

Amazing...almost looks organic, like a rear view of fossilized trilowbytes... (misspelling inserted to minimize Google captures... )

Posted by: Jeff7 Jan 4 2006, 01:07 AM

With all the concern about Google, why not just prevent the site from being indexed?

http://www.google.com/webmasters/remove.html#exclude_website.
There's a tag or something that can be placed in the page or on the webserver that'll instruct Google to pass over the site when it is doing its indexing.

Posted by: mars loon Jan 4 2006, 02:11 AM

Steve Squyres latest update (Jan 3) talks about this. see his quote below:

"Over at Meridiani we're still at the Olympia outcrop, but we have come to realize that our extended stay here has yielded a very important find. We've spent a lot of time recently taking high-resolution Pancam images of the rocks around us at a range of lighting angles, to bring out fine details in the layering. And if you look at one of the Pancam images that came down on Sol 690, you'll see that we have now found the best example of small scale "festoon cross-bedding" that we've seen the whole mission.

When you're talking about layering in rock, "festoon" geometry means little nested concave-upward shapes. They look like little smiles a few centimeters across. This kind of layering is seen in sedimentary rocks on Earth, and when it's found at small scales like this it provides solid evidence for deposition in flowing liquid water. It was small-scale festoon cross bedding that led us to conclude that liquid water had been present not just below the surface at Meridiani, but occasionally at the surface as well. If you're interested in the gory scientific details, check out the paper by Grotzinger et al. that we recently published in Earth and Planetary Science Letters.

We've seen small-scale festoon cross-bedding before, of course, at Eagle Crater and again at Endurance Crater, but this is by far the best example that we've seen yet. Once we've got Opportunity moving again, our first task is going to be to drive over to this spot and take a big Microscopic Imager mosaic on it, to document the cross-bedding in detail.

The thing I find really striking here is that if it hadn't been for the busted wire in the motor on Opportunity's arm, we would have blown right by this without seeing it. Ironic."

Posted by: Shaka Jan 4 2006, 02:32 AM

...and the clock is ticking. First one to post the image with the festoon bedding circled will win our Grand Prize!

Posted by: Shaka Jan 4 2006, 02:48 AM

Well....O.K....I'll take a chance....
How about...

Posted by: CosmicRocker Jan 4 2006, 03:13 AM

There's little doubt in my mind that that is the image Steve Squyres was talking about. I was just about to post it in the Erebus topic, but thought I'd check here to see if anyone had beaten me to it.

When that image first showed up the other day my jaw dropped. It's spectacular.

Posted by: Bill Harris Jan 4 2006, 04:10 AM

I've been following the series of low-incidence lighting images for a couple of weeks. This technique can bring out fine textural detail on the surface.

--Bill

Posted by: Anoolios Jan 5 2006, 09:18 PM

There is festoon bedding all over the place in that image, and I agree that its absolutely spectacular. It looks remarkably like patterns that can be obtained in a "wet sandbox" setup with a pump for water and wet sand.

I cannot imagine an explaination for these features other than flowing water.

Posted by: Bill Harris Jan 6 2006, 02:27 PM

For general information, here is an overview of sedimantary structures/bedding:

http://www.uwgb.edu/dutchs/PETROLGY/Leaverite-SedFeat.HTM

--Bill

Posted by: CosmicRocker Jan 7 2006, 08:02 AM

I think that really was the nicest collection of sedimentary structure images I have come across on the web. Thanks for that. Those who might want to learn a bit about geology might want to review that page.

I thought it was funny that this section of his web site was devoted to http://www.google.com/search?hl=en&q=define%3Aleaverite&btnG=Google+Search

Posted by: CosmicRocker Jan 7 2006, 08:09 AM

Then, there is this confirmation of the sighting.

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20060106a.html

Posted by: Bill Harris Jan 7 2006, 09:42 AM

I got a chuckle out of 'leaverites' once I remembered what they were; it's been decades since I've heard that term.

Hopefully we'll get some use out of those fine sed structure reference images here and AT THE MOGOLLON RIM (hint,hint) _and_ over at the Inner Basin (which is really starting to get interesting).

Another thing I noticed in that confirmation mosaic at the JPL site: just below center there appears to be a small post-depositional slump in the sediments. Or so I think; it looks a _lot_ like something I've seen locally.

A crop and close-up from the JPL image is attached.

--Bill

Posted by: sranderson Jan 13 2006, 06:04 AM

I am somewhat concerned that what is being called festoon crossbedding is merely differential erosion of flat layers that have no festoon "smiles" intrinsically.

The image evidence presented so far at Erebus is of rocks with an erosional exposed surface that is nearly coincident with the plane of the layers themselves. This makes it hard to tell whether or not the layers have real peaks and valleys or if they are more eroded in a pattern that makes it look like it has peaks and valleys.

I have seen numerous RAT grinds with the rotating axis perpendicular to the layer plane, but few if any that are parallel to the layers (to grind against the edge of the layers). If we could find a festoon-candidate outcrop with a good straight up-and-down side exposed, then we could put the RAT directly against the edges of the layers and grind off any erosional effects.

Then we could definitively say whether or not there are festoons -- unless the layers are so homogeneous that the grinding operation erases the character of the layers themselves.

Scott

Posted by: alan Jan 13 2006, 06:27 AM

Closer look next week

http://athena1.cornell.edu/news/mubss/

Posted by: Bill Harris Jan 13 2006, 10:14 AM

Me too. Looking _at_ an eroded bedding surface is somewhat iffy. What I was hoping was that Oppy would look at some of the vertical joint planes exposed at this current outcrop. Or/and/also at the Mogollon Rim area 80 meters away.

<chant>
Move Move Move
</chant>

--Bill

Posted by: Airbag Jan 13 2006, 05:52 PM

I'm glad it is not just me then - I've wondered that right from the first such sightings in Eagle Crater. I've been tempted to make a model using layers of cardboard to see if I could simulate features that look like festooning, but have not had the time so far...

Airbag

Posted by: sranderson Jan 15 2006, 07:19 AM

Here are two photos of a layered rock I have. The first one is looking directly at a surface that is fairly parallel to the layers. I can make myself believe I see ripples here.

The second one is from the side -- and it shows that all the layers are flat and parallel to each other with no ripples.

Posted by: Reckless Jan 15 2006, 07:01 PM

I can see that laminations can weather to look like cross bedding etc. but I find it hard to believe the the team at JPL would not take into account the strike and dip of the bedding plains before anouncing festoon bedding, but maybe I expect too much of the guys working by remote control in a very difficult invironment.

Reckless

Posted by: elakdawalla Jan 15 2006, 08:17 PM

A key question is whether you can see one set of layers terminating against another layer. You will not see that kind of geometry no matter how you slice a parallel-layered rock. Look at those pictures and see if you can see "T" shapes where one layer dead ends into another, and you know that something came along and cut one set of layers before depositing another, which happens all the time in these shallow-water ripple deposition environments.

--Emily

Posted by: Reckless Jan 15 2006, 10:59 PM

I Think I see "T"s

Posted by: CosmicRocker Jan 16 2006, 05:16 AM

Festoon bedding can be confidently observed in plan view, imho. The "T" geometry Emily pointed out is, I think, quite diagnostic. But in this case, we can see the "T", and several pretty stupendous examples of nested bedding in ripple troughs. There must be an "official" name for that geometry, but I'll be damned if I can remember it. I've always thought of them as "eye" structures, because the nested beds form elliptical, or eye-shaped patterns when sliced this way.

I agree that all kinds of shapes can be created by differential weathering/erosion in rocks with layers, but it really doesn't appear to me that these particular layers are horizontal/flat. I really thought the fortuitous discovery of this special slice through the bedrock was pretty convincing.

Posted by: Airbag Jan 19 2006, 03:51 AM

On sol 705 Opportunity took a series of L6 "super res" images of various rocks showing fine layering details; I stacked them, resampled them by a factor of 1.5 and then sharpened them a little using an unsharp mask.

Airbag

Posted by: CosmicRocker Jan 19 2006, 04:53 AM

Thanks, Airbag. Very nice. I saw those come down and thought, "I should finally try to stack those with Astrostack." It's something I've been meaning to try since the super-res they shot at Burns Cliff. I got busy with other things, as usual, but I did take the time to compare your stacks with the raw individuals, and there is clearly a significant improvement in resolution.

The one thing I don't understand about these things is, why do they always take these sets as subframes? Is it a bandwidth issue, or do they use subframes simply because they are not concerned with the surounding view, or is it something else entirely?

Posted by: Airbag Jan 19 2006, 04:08 PM

Thanks CosmicRocker; I use RegiStax v3 myself. I suspect the reason these are subframes is for bandwidth reasons, as you wrote. It is just these rocks they are interested in seeing in more detail, and not the soil in between.

It seems to me in this case at least some of these targets were a little too close for the pancam to reach focus, so this might be one way to get a bit more information back. On the other hand, we are using lossy compressed images as a source, so who knows!

Airbag

Posted by: dilo Feb 23 2006, 10:09 PM

I love these late evening shots!

(Sol737, L247 filters)

Posted by: Nix Feb 23 2006, 10:35 PM

I can see why! I'd love to see a big panorama shot in the evening. I wouldn't like to match the frames of such a pan though, given the rate at which the lighting changes at dawn/dusk...

Nice mosaic
Nico

Posted by: djellison Feb 23 2006, 10:43 PM

If you were parked up for say, 50 sols or so, you could take one column every evening...

Oops



Doug

Posted by: alan Mar 10 2006, 03:26 PM

More festoons?
http://qt.exploratorium.edu/mars/opportunity/pancam/2006-03-10/1P194853277EFF646BP2547L7M1.JPG

Posted by: Shaka Mar 10 2006, 07:57 PM

Hee Hee! Yeah, that one had me forward in my chair! At first hello it looks like a bonanza, but, on closer inspection, I wouldn't bet my canoe on any of it. Some areas I might use the MI on, though.