Solander Point - Page 13

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Posts: 344

Reply: 241

PostPosted: January 1, 2014 8:19 PM 

Kye, what about the Esperance discovery?

Possibly montmorillonite. Isn't that more significant than the previous nontronite identification?


Posts: 344

Reply: 242

PostPosted: January 1, 2014 8:54 PM 

Notice the crack in the rock that passes through a newberry on the right. This suggests the rock may have been there before the Endeavor impact (which may have created the crack).

Kye Goodwin

Posts: 1166

Reply: 243

PostPosted: January 2, 2014 1:30 PM 

Barsoomer, re your 241, I don't know the significance of the discovery of montmorilonite at Cape York compared with the rest of the long list of indications of chemical water activity that have been discovered at Meridiani. There's no doubt that such activity has taken place, but there hasn't been much progress in the mainstream understanding of the context in which the water acted.

I'm not trying to argue that the cape materials we've examined at York, Knobby Head and Solander are the same as the bright rock, but while the mainstream emphasizes the differences I am pointing out the similarities, the clay present in both, the fine "layeriness" (sorry) of both, the limited maximum grain size of both and the presence of spherules in both. The differences suggest that the water context was not exactly the same in each case, but as a fan of Occam's Razor I want to connect them all, not proliferate explanations.

We don't yet have the basic outline of the sedimentation and erosion processes that have taken place at Endeavour Crater. I think the rover team is leaning toward explaining all the cape materials as bedrock that predates the Endeavour impact but has been uplifted during that event. This might be plausible for the low capes but I'm just not going to buy it for the tall capes. They are too tall and narrow to be likely uplift. Without close examination they would be assumed to be ejecta piled on the crater rim. Trouble is, on close examination the material we've seen so far doesn't look like the proximal ejecta of Endeavour. It looks like distal ejecta that had enough runout distance to become sorted and layered. Hence the mainstream need to explain it as bedrock created by an impact pre-dating Endeavour.


Posts: xxx

Reply: 244

PostPosted: January 2, 2014 6:27 PM 

The reason I suggested/guessed mylonites, or phyllonites is that you do tend to find those in major meteor impacts on Earth.

Esperence is Noachian in age. I tend to think that the area would have been wet at the time of impact (?) so hydrated minerals such as mafic chlorites or similar would make sense.


Posts: xxx

Reply: 245

PostPosted: January 3, 2014 10:21 AM 

Sol 3535 (Jan 3, 2014 ) MI closeup 3D of rock on Cape Douglas:

After taking this image 2 weeks ago:

Hmm. Still a lousy image. The APXS measurement is a few cm away from the one done a few weeks ago.


Posts: xxx

Reply: 246

PostPosted: January 3, 2014 5:17 PM 

Sol 3509 (Dec 7, 2013 ) false color panorama at Cook Haven:

8 more frames of the large L257 panorama from the current position.

When all the frames are posted I will do a full pan and post to gigapan.


Posts: xxx

Reply: 247

PostPosted: January 8, 2014 5:13 AM 

Latest update from the Planetary Society:



Posts: xxx

Reply: 248

PostPosted: January 8, 2014 12:41 PM 

Sol 3536 - 3538 (Jan 4-6, 2014) panorama of the rover deck at Cook Haven:

I could not get autostitch to combine all the images.

The "big guys" should produce a complete pan.

Here is a collection of interesting spots on the deck:

The large spots still clinging to the rover after so much travel is surprising to me. Perhaps some form of ( partial ) vacuum welding?


Posts: xxx

Reply: 249

PostPosted: January 8, 2014 1:37 PM 

Sol 3540 ( Jan 8, 2014 ) 3D false color of new target rock on Cook Haven:

Today Oppy moved about 5 meters to this new target.

I wonder what the "stuff" in / on the top of the rock is?


Posts: 344

Reply: 250

PostPosted: January 8, 2014 10:15 PM 

Intriguing "stuff." Could that be another piece of crumpled-up "plastic"?

Kye Goodwin

Posts: 1166

Reply: 251

PostPosted: January 9, 2014 2:02 AM 

I'm getting an Error message from Movable Type when I try to post (Invalid Request Corrupt Character Data) so I'm trying this short post as an experiment.

Kye Goodwin

Posts: 1166

Reply: 252

PostPosted: January 9, 2014 2:05 AM 

Kevin, Thanks for posting the latest Planetary Society Update in your 247.

This paragraph from the Update is of special interest to me because I've been pointing out since Oppy first reached Cape York that we have failed to find any abrupt contacts, but have seen only gradual transitions at the Cape margins. The rover team has now identified a "graduational" contact within Cape York:

In February, Opportunity climbed further up the hill to check out the newberries, small spherules like it had found in Whitewater Lake, at Flack Lake, and then to look for the contact or boundary between the Shoemaker Formation impact breccias and the older Whitewater Lake and Copper Cliff outcrops that sit just stop the Whitewater Lake unit on Matijevic Hill. Rather than a clearly defined boundary, they found "a gradational contact," "a mixing of materials" as the crater ejecta were emplaced said Squyres. "The month was devoted mostly to trying to understand how the clay bearing stuff we see at Whitewater Lake with all the newberries in it is related to the Shoemaker-like stuff further up the hill."

Another excerpt:

Endeavour, however, is a big crater – 22 kilometers across. "We're not going to find a uniform set of breccia deposits," Arvidson pointed out.

Yes, there's been a lot of distinct variety over very short distances, too much variety for the tall cape material to fit comfortably as Endeavour's ejecta, as I've pointed out before.

And another:

Even though this is Opportunity's sixth Martian winter, it may be the most productive and rewarding winter it's ever had, given the exposure of bright rocks and outcrops at Cook Haven. "Where we are now – the target Cape Darby, which is on Cape Douglas – the area, is an impact breccia, because you can see the clasts and the matrix and it looks more like Shoemaker Formation than anything else," said Arvidson. "What we're trying to do now is figure out what exactly they are and how they fit into the overall stratigraphy of the rim of Endeavour Crater. Are they all breccias? If so, what types of breccias and how do they fit into the impact event. Or are we actually going beneath the breccias in this place to get the pre-existing rocks?"

I guess the jury is still out on whether Cook Haven is uplifted bedrock or ejected breccia. (It is neither, IMO.) The team is less unsure in its identification of at least one of the many formations at Cape York as pre-Endeavour bedrock:

"It began with Opportunity measuring the Whitewater Lake area, now part of the Matijevic Formation, very unusual rocks that probably pre-exist the impact event and were just uplifted on the rim rocks," reviewed Arvidson.

Another excerpt on another topic:

If this thinking bears out, "then it indicates the very fine-grained, glassy materials were altered, after the impact materials came down, in the presence of water," said Arvidson. That would not be at all surprising. "There have been lots of models of that show there would be hydrothermal circulation set up with ground ice after an impact on Mars. We're just trying to sort everything out at this point and also see if we can find more of these materials this winter."

Interesting to me because here water chemistry alterations are being attributed to impact, not to an ancient climate for a change.


Posts: xxx

Reply: 253

PostPosted: January 9, 2014 10:06 AM 

Sol 2882 3538 ( Mar 3, 2012 - Jan 6, 2014 ) animation of spot on the rover deck:

The string may have gotten shorter - but there are soo many problems comparing the two images ( filters (L257 vs L456 ), camera pointing, lighting, image resolution... ) that it is difficult to make a judgment.

But the fact that the string is in exactly the same place after 656 sols is distressing.


Posts: xxx

Reply: 254

PostPosted: January 9, 2014 8:10 PM 

Sol 3541 ( Jan 9, 2014 ) MI closeup colorized panorama of the rock Cape Elizabeth Pinnacle Island in Cook Haven:

with location links.

This rock has the strangest infrared spectra of any rock seen by Oppy!

Any ideas?

Bill Harris

Posts: 3

Reply: 255

PostPosted: January 9, 2014 10:32 PM 

I'd think it's highly weathered or has undergone intense hydrothermal alteration. In R721, it shows that intense crimson colr we've seen before.



Posts: 344

Reply: 256

PostPosted: January 9, 2014 11:35 PM 

Perhaps we could be seeing the underside of a piece of gypsum with different colored layers.


Posts: 344

Reply: 257

PostPosted: January 9, 2014 11:39 PM 

Horton, check out the second image of your reply 248, just to the right of the rover "wing."


Posts: xxx

Reply: 258

PostPosted: January 10, 2014 8:09 AM 

on R254 last image, does red represent warmer? Any idea what's that temperature, and why it's warmer than the surrounding? Maybe it's some kind of metal that warms up in the sun? Was this seen before?


Posts: xxx

Reply: 259

PostPosted: January 10, 2014 11:59 AM 

The color map for my infrared images is:

R = max ( R5, R6, R7 )
G = R4
B = min ( R2, R3 )

The RGB differences are usually small, so I create an enhanced difference version:

R' = G + 8 * ( R-G )
G' = G
B' = G + 8 * ( B-G )

which I further "white balance" to get rid of the overall green tint.

The "colors" have very little to do with object temperatures but are instead a measure of the reflectance of sunlight at the filter wavelengths.

The enhanced difference false colors are useful for saying "this thing is like ( or not like ) that thing" - not identifying the minerals.

However, I am sure the MER team can calculate a rough spectra ( 5-10% accuracy ) from the original 12 bit data and have a library of possible spectra to help narrow down the possibilities.

Here is an animation of the rock viewed through the infrared filters:

The filter values are the averages of an area in the center of the rock. The variance in the area ranged from 11 to 19 over the filters.

As I said in reply 254, this range of brightness in the infrared is unique ( as far as I can recall over 10 years! ) for Opportunity.

Bill Harris

Posts: 3

Reply: 260

PostPosted: January 11, 2014 1:35 AM 

Gypsum is but one member of an important class of hydrothermal minerals that we should be focusing on.

Hydrothermal activity related to impacts has been observed to be an important process on Earth, and has to be as important or more so on Mars. Oppy should be searching for critical clues related to these hydrothermal processes and should put the "clay pot at the end of the rainbow" on secondary status.

Here are a few links to impact-related hydrothermal processes that I've come across recently:

New evidence for persistent impact-generated hydrothermal activity in the Miocene Ries impact structure, Germany

Impact-generated hydrothermal systems on Earth and Mars

Onset of Impact-Generated Hydrothermal Systems


Martian post-impact hydrothermal systems incorporating freezing

Google search on:
"mars impact hydrothermal"


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