On the Road Again - volume 4 - Page 11

sol 2136 3D detail of uneven bedrock near Concepcion crater:

This was taken at the sol 2134 location just before moving.

For those of you unable to do the crossed eye trick to see 3D you might want to try the Loreo Pixi 3D viewer to view 3D. The viewer costs $2.50 + $1.00 postage in the USA.

A Flickr fan of my side-by-side 3D sent me one to view a 3D show of Mars pictures that he recently produced and I was surprised how well it worked.

You will still have to download the 3D side-by-side images and use StereoPhoto Maker to switch the left and right images - but I have always recommended that program to view the 3D images anyway.

I would be interested in any one else's, er, view on using this viewer. If there is enough interest I will post the 3D images uncrossed-eye on Flickr.

It is interesting that the "big guys" are also interested in the uneven bedrock in this area.

What catches my eye are the chunks of conglomeratic ? material which may mean the crater has penetrated that layer which we have only seen glimpses of before.

Oooh, Hort, I missed that-- there were a sackload of subframe sky and "oddball" images coming through at that time, and I was focussed on images of the Big Enchilada. Fascinating old erosional surface. Have you seen other stereo Pan- and Navcams taken about that time? I've not looked yet.

Ben, I'm not so sure that it is comglomeratic as mush as recent "sandblasting" of freshly fractured rock surfaces. I do hope that it is something different-- we'll see soon enough.

--Bill

RE: My post #152

Lunar and Planetary Science Confererence paper by Tim Parker:

http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2638.pdf

I've been looking at the topo map included in this paper, and although the contour lines look good, the elevations marked on some of those lines do not make sense. It may be me, it may be that I'm misreading the fuzzy lettering. I'm trying to work up a topo x-sectn.

Has anyone made sense of it?

--Bill

I'm hoping Oppy can get to the edge and peep inside.

Hort; Thanks for the info on the Loreo pixi stereo imagers. I'll try to get one asap.

Winston

RE: Topographic confusion

Never mind, that problem is being discussed at the other place-- the "-1325" elevation just east of Concepcion is really "-1395" and everything adds up...

--Bill

I can't do the crossed-eye trick, but I can do a similar parallel eye trick without needing a viewer. To view your 3D images, I bring up a duplicate browser window and put your left image at the right edge of your right image. It would be a great convenience if you posted some LR pairs.

All, the LPSC 2010 Abstracts are out:

http://www.lpi.usra.edu/meetings/lpsc2010/pdf/program.pdf

I've been reading and trying to get around to posting about some of the abstracts that are most relevant to this thread. First I'd like to re-post this one article that Bill Harris pointed out a few pages back:

http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2638.pdf

I just noticed Bill Harris has posted again about this map in reply 204, Hi Bill. I think that the map does make sense though the contour line labels are barely legible. The negative elevations are a bit confusing maybe - larger numbers (in absolute value) denote lower elevations.

The contour map is the best that I have seen of Oppy's neighborhood. It includes some surprises, for me at least:

The immediate rim of Victoria Crater is raised above the annulus but this rise is too small to show up on the map. The surprise for me is that the annulus itself is a fairly tidy circular depression about 5 to 10 metres deep. How can this be explained? It really seems that what was once the ejecta field of the crater has not only been cleaned of all ejecta but has also somehow been significantly lowered to a level below the original plains surface?! I'm not buying that the Victoria impactor landed in a pre-existing depression, theory does not predict that the annular area would be lowered by the original impact, and I can't imagine what sort of erosion process on the plains would be accelerated by the presence of a crater 100's of metres away or that could produce the smoothest plains surface that we've seen anywhere.

Another surprise, perhaps related, is this: Hills at Endurance are now visible on the horizon and I have always assumed from the orbital images that these hills are rim ejecta piled up around the crater wall. According to the map, though, the hills along the west (near) side of Endurance are actually inside the crater with their bases well below the rim. HUH? Anybody? What does this imply about the history of Endeavour Crater? Does it mean that as with Victoria, most of the bedrock area originally covered by ejecta has eroded faster than the plains in general? Sometimes I wonder if we have any idea at all what created this landscape.

One more note: the article mentions "gravel piles" which I've been calling "cobble mounds" and reveals that there are more of these visible ahead in the HiRise images and that visits to them are planned.

Please substitute Endeavour for Endurance in my previous post (relpy 20 .

The topo map in the "2638.pdf" paper still has a couple of confusing features. On large scale, I think it's generally accurate, but there are some idiosyncrasies at smaller scales (like around Victoria and the rim of Endeavour). Which happens if you have coarse data and you're applying it to fine details. I need to trash it around a bit more, but I think it's basically OK as a representation of the topography between Victoria and towards Endeavour. The endpoints are a bit fuzzy...

It's 60 degF today, and I've got yardwork to do before it turns Wintry again...

--Bill

Bill Harris and Kye Goodwin - thanks for the links.

Not sure that I follow you Kye. Although as Bill says it is hard to interpret between the big brush approach and small scale mapping around the craters, it seems to me that the rim and annulus at Victoria are shown as raised above the surrounding plain? The rise in elevation to Victoria seems to fit the findings of eolian deposits in the upper level of Victoria compared to water flow features at Eagle and Payson. Fits a water table/Playa scenario does it not?

serpens, re your 211, Looking once again at the map, no, I still think that it shows a depression around Victoria. The vicinity of Eagle Crater is at about -1385 m. Oppy climbed to about -1370 m near Erebus and then descended to -1390 m before reaching the rim of Victoria. This doesn't fit very well with the text of the article that refers to a 30 m climb from Eagle to Victoria but the map contours seem consistent. Where the labels are illegible, counting from the nearest readable one checks out.

Anyway, the map could be wrong, but if it is right then I can't explain it at all. The depression around Victoria is subtle but it is hard to believe that it is in no way related to the crater. On the other hand it is hard to explain why the crater would have a subtle concentric depression surrounding it nearly one additional crater diameter wide. As I have said, theory does not predict anything like this for simple impact craters. This great overview paper by Melosh and Ivanov is still free:

http://huminf.uib.no/~beev/misc/impact%20craters/impact_crater_collapse.pdf

That leaves some sort of post-impact process lowering the annulus to form the depression, but I'm stumped as what this could be.

sol 2138 ( Jan 28, 2010 ) navcam 180 pan of the north side of Concepcion and looking northwards

with a link to 3D pairs.

The move was about 12 meters.

Great site. I'm already seeing some wonderful sights.

The "depression" around Victoria is clearly erroneous. Remember that we started seeing "The Beacon" about midway between Erebus and Victoria and we've seen The Beacon even past Santorini. No way it's in a 30 foot hole. Clearly Beacon is the local topographic high and Victoria impacted just to the south of it.

Hort, do you know where on the HiRISE image your "sol 2136 3D detail of uneven bedrock...taken at the sol 2134 location" is located? Or on the NavCams? I've looked for a couple of dsays and I can't spot it.

--Bill

Bill, if you follow the Location link in the Flickr comments for the image you will find the, 3D location in the nacvam pan as an image note marked "3D location".

You will have to move the mouse pointer over the navcam pan image to see the image notes. The image notes will appear as small rectangles on the image.

The "sol 2136 3D detail of uneven bedrock...taken at the sol 2134 location" image note is small square on the left side of the panorama.

I try to do this for all the pancam and MI images that I post on Flickr. It's a lot of work but I think it is useful to link images together this way.

SO, to summarize, if you want to locate an image in a larger context, follow the "Location" link in the Flickr image comments - and if you wish to see a part of a Flickr image in more detail, follow the link in the image notes.

Hope this helps.

Ah, that's right. I'd forgotten about that useful feature.

Thanks for the reminder.

--Bill

Rock at right near the bottom has interesting cross-layers. Note the "X" shape on the right hand side. How can layers intersect like this?

Bill Harris, re your 214, The Beacon's visibility from a great distance doesn't tell us much about its elevation. The question is what ground is between the viewer and the landmark that might block the view. The depression around Victoria is subtle and 100's of meters wide. The beacon is elevated a few meters above the annulus so it is visible from other places in the depression. The local elevated feature of the Beacon is too small to show at the scale of the map.

Interesting. We finally see a contour map and it is surprising, and not only to me. Some find it so surprising that they doubt it's accuracy. Those contour lines bending around Victoria but 100s of meters away from the rim might be an important clue to the history of the crater. On to Endeavour! It seems to be even harder to explain.

Here is the Victoria HiRise DEM ( Digitial Elevation Model ) from HiRISE Mars Digital Elevation Models: Difficult to Build, Easy on the Eye.

To my eye it is clear that the apron around the crater slopes upward - not downward. ( The color rises from yellow-green to red approaching the rim. )

re 217,
Those cross-bedded sedimentary boulders can be explained as fragments of deposits that, as they originally precipiated, were tossed and turned by storm-generated waves and/or currents on the bottom of a shallow sea. Similar sandy formations are visible in the exposed face of the Scarborough Bluffs, north shore of Lake Ontario (90,000yrs bfp).