I'll be very curious to learn the difference between this bright layer and the darker layer further down. Evaporite versus lack of evaporite? Differing salts in the evaporites? From a distance, this seems the major geological feature in the bedrock hereabouts. Has MiniTES weighed-in on the question yet? Or has Oppy been too far away?

If Oppy is currently "above where the berries were made" then she would have to be higher than the northern edge of the crater since the surfaces in and around Bahia Blanca and The Valley Without Peril were covered in berries (as is fairly clear in this stitch of The Valley by Ant103 ). I don't think we are higher but I'm open to correction.

Just remembering an early interpretation of the berry distro - not saying it explains everything we see. Covered in berries doesn't mean full of berries (although that image would suggest some berries erroding out of rock) . It's no secret that the berries seen within rocks got smaller, and then vanished, as we headed south from Endurance.

Doug

Minus the RAT holes, too. When Steve said they wouldn't deviate from the path to the band, he really meant it...

Thanks Doug, I remember I watched that at the time, and I actually discovered the talk on my hard drive.
So the berry layer should be 5-10m lower in the crater, as SS mentioned. It would be nice to see it as we go deep down. Go girl

PS. I just saw helvick's post. SS said in the talk that berries were thrown out during victoria's creation and that's why they reappeared once we got close to the crater. So still, the berry layer should be found deeper inside the crater.

I don't know whether we should be surprised or not about how agressive they're driving into VC as compared to Endurance.
In one hand, they've got confidence in Oppy's capabilities increases since she left Endurance + I guess they've prioritized the white layer.
On this other hand, don't we have any interest in brushing/rating = studing what lay between the rim and the whiter layer ?
Thanks

The layer above the white layer is just jumbled ejectra. Some is from deep in the crater, but there is no way to tell from what depth. So, start looking at the old top--the white layer--and then examine deeper layers further in VC.

This is the first time they've had an opportunity to examine an ejecta layer on Mars. It deserves closer study.

I agree that the ejecta layer is worth studying, but after we have studied the deeper, intact layers. It will be relatively easy to interpret the chronology of intact layers, and to recognize significant past events that precede those we have already seen in Endurance and elsewhere. It is the deepest intact layers that offer us the best chance of major discoveries, and we should proceed there with some dispatch (granted that Oppy's lifetime will be finite). After we know what's at the deepest exposures, we can then work our way systematically back up the section, filling in the blanks and ultimately doing a leisurely perusal of the ejecta blocks, being better able then to recognize their probable stratigraphic origins, including any that might be from deeper than the intact exposure.

I agree with Shaka.

I agree too, best thing is to focus. But anyway, I'm a bit surprised they didn't even stop for one sample! May be they'll get back up before plunging deaper ?

I have to disagree with Alan -- this is not the first ejecta blanket we've had a chance to study. The first couple of meters down into Endurance were what Squyres called a "dog's breakfast" of jumbled ejecta, and Oppy also skipped down past that until she got down into the intact layered stratigraphy.

The whole point is that intact bedrock tells you a much more complete story than jumbled ejecta. Yes, the science teams *may* take a good look at anything they see in the jumbled ejecta as they exit the crater that looks different or unusual, but even if they do, they'll have no clue from what stratigraphic section anything in the ejecta came. So simply, from a geological standpoint, it makes a lot more sense to study the intact bedrock.

-the other Doug

Ha! A dog's breakfast? I missed that comment. If you could provide a link to that, I would be most appreciative.
I don't really see a lot of value in RATing and analyzing random ejecta blocks, unless of course, we come across something new and completely different. But I do recall a previous comment from Steve Squyres that this would be an opportunity to study a cross section through an impact blanket, so we may eventually see some investigations in the jumbled ejecta. It seems though, that the MER team has expressed more interest in the thin, white layer just below the ejecta.

I find their explanation of the interest in that layer fascinating. Just prior to the ancient impact that formed Victoria Crater, the surface of the light layer was the surface of the land in this area. By studying that surface they hope to learn something about the interactions between that surface and the atmosphere/climate that existed billions of years ago, just prior to the impact. It's probably a bit more complicated than that, but I can imagine it should be an interesting contact to investigate. The whole "bathtub ring" analogy has been overused, but there really are a number of geochemical or diagenetic alteration contacts that we need to watch for. The bathtub rings that have been mentioned in various places are subsurface contacts where groundwater has altered the original rock/sediment. The appearance of concretions/berries embedded within undisturbed bedrock is one bathtub ring that is expected.

I have really been hoping to see the contact between the bright layer and that dark one in detail, too. The color changes and so does the texture of the rock. I can't imagine they would neglect it. From a distance, it resembles the Whatanga contact which was observed in Endurance Crater. That contact is not a stratigraphic contact between two layers deposited at different times. It has been interpreted as a chemical alteration layer associated with the upper, capillary fringe of a paleo-groundwater surface. Here is slinted's color version of that contact from Endurance on sol 310.


If they can find any kind of correlation between the rocks found further north and these in Victoria, it will be an important accomplishment.

I don't have a link, but I do have a cite:

"When you look at the Pancam pictures we took from the top of Karatepe a couple of weeks, ago, the upper part of the slope is a jumbled dog's breakfast, made up of blueberry-laden rocks that look like the same stuff we've been seeing for months. A few meters down the slope, though, everything changes. The rock becomes contiguous and regularly banded, the jumble giving way to intact stratigraphy."

Steve Squyres, "Roving Mars," First Edition (hardback), © 2005 Steven W. Squyres. pp.346-347

-the other Doug

I'm really loving this image looking back up, with the tracks through the rim ripple/dune on the horizon.

Nice view of the 'dog's breakfast' as well. The nice layers in front of us do look like a much more tempting target, I can see why we skipped straight down.

James