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Looks like the new bright stuff churned up by Spirit has gotten the attention from the PI on Mount Itacha

Spirit Front Hazcam

Latest Steve update

So what is this new stuff (which we have named Arad)? The same kind of salt? Something different? Similar concentration or even saltier? It was too tempting a target to pass up, and we're going to spend the weekend doing IDD work on it before moving on.

[nprev]

Could be that the different tints are due to various states of mixture between the white stuff & the "normal" soil...could also be some other sorts of transition metal compounds, possibly another result of water interaction...odd.

BTW, that rock on the right edge of the trench looks a bit shiny & metallic in this view. Is this an artifact of the color processing, or is this another meteorite candidate?

[CosmicRocker]

Oh, no doubt there is some mixing going on with some of the tints. But there are clearly several end-members contributing to the mix.

[Nix]

some stereo on the trenching;


color stereo @ 50% and anaglyph, Spirit, sol 721

Looks even more Spectacular then PR1 and 2 I think, hmm...back to that 'old' data...

Nico

[Bill Harris]

This is quite a site. I think that some of the range of colors we see are from the mixing of differing tints, but also from differently colored layers in the deposit. Or so it seems to me. The mechanical properties of the material are unique-- I'd say "fluffy", too, but just for lack of a proper word. It has a fluidity to it, look at how it has flowed around that vesicular rock on the right. Not to imply water-wet.

On future Rovers we need a "trenching tool", a narrow blade that can be dropped down 0-1-2-4-6" and locked down; the digging is accomplished by the Rover driving. The wheel-trenching is adequate, but fro fine structure it has the subtlety of a sledge hammer.

The blue color is an intense indigo. NOT subtle. Let me dig thru my archives, but here is a recent example from the Comanche area. This is apples/oranges since mine is an L257 and yours is an L456. The other examples I'm thinking of are from "around Larry's Leap" in the Hills.

--Bill

[nprev]

Spectacular, Nix!!!!


The sharp delineation of the white material is incredible.

This may or may not be germaine to the topic, but about thirty years ago after Viking I made a Mars jar for a science fair project and mixed the "soil" up based on the Viking 1 composition analysis. I used fine-powder sulfur and magnesium (I think) oxides in addition to various iron oxides for the soil mix, sucked out the air with a vacuum pump, replaced it with basically pure CO2, and tried to grow a couple of succulents (also had a nice red lichenated rock in there...looked awesome!)

The point of that story was that no matter how thoroughly I mixed the soil, the Mg oxide always seemed to settle out in thin, uniform white layers just under the surface; the entire soil depth was about four inches. At the time, I accepted this as a consequence of the purity of lab-stock compounds and my own amateurish mixing...now I wonder if maybe the model soil was a LOT more accurate than I thought, at least with respect to Gusev...

[nprev]

This is quite a site.  I think that some of the range of colors we see are from the mixing of differing tints, but also from differently colored layers in the deposit.  Or so it seems to me.  The mechanical properties of the material are unique-- I'd say "fluffy", too, but just for lack of a proper word.  It has a fluidity to it, look at how it has flowed around that vesicular rock on the right.  Not to imply water-wet.

On future Rovers we need a "trenching tool", a narrow blade that can be dropped down 0-1-2-4-6" and locked down; the digging is accomplished by the Rover driving.  The wheel-trenching is adequate, but fro fine structure it has the subtlety of a sledge hammer.

The blue color is an intense indigo.  NOT subtle.  Let me dig thru my archives, but here is a recent example from the Comanche area.   This is apples/oranges since mine is an L257 and yours is an L456.    The other examples I'm thinking of are from "around Larry's Leap" in the Hills.

--Bill

Hmm. Cupric oxide, perhaps? That's a REALLY deep blue...and it's also a common precipitate/leach product in mine tailings.

[edstrick]

I grabbed Alan's color version, did a judicious contrast stretch on the bright end (photoshop curves) and an edge sharpening on the brightness. Brings out quite a bit of detail.

There was a salt-patch on the drive from Bonneville to the spur, about 2/3 or 3/4 of the drive, more in the vicinity of "pot of gold" rock, as well as the big patch found later. Similar enhancements on all of them show quite a variety of color differences within the different high reflectance materials, but I can't easily find my old files, buried on non-connected hard drives and over 100 "misc' CD's.

Attached thumbnail(s)

 

[helvick]

Am I right in thinking that we seem to have a pretty well delineated and fairly thin layer of white stuff here, not just a layer of typical Gusev surface material overlaid on a deep bed of whatever this white stuff is?

[edstrick]

I think so.. it's spotty in distribution, not at all clear why.. Here it's pretty clearly in a drift of "fines" on rubbly regolith, not in the fines part of the rubble itself. This deposit must either be an aeolian layer, or salts deposited up into the fines by groundwater, which seems to have not cemented it. A really big question in that model is how is it loose and totally crumbly, not cemented.

I too have continually wished for a trenching tool on these rovers, as I commented some months back. Scuffing works, but it almost totally trashes any interpretible stratigraphy.

[sattrackpro]

I’m really enjoying watching this odyssey here... so much fun! I’m most thankful for this site, and everyone’s great work.

But, looks like next week, after working these ‘bright spots’ over real good with the Moessbauer, it’ll be very interesting to see what kind of dune-dodgin’ Spirit will have to perform to get ‘round the horn.’

It may be the rocks ahead (by the third dune down the road) could make for difficult passage. Does anyone think ‘a long way around’ could be necessary? There’s also what looks like a large fourth dune... it gets interesting’r and interesting’r!

Here’s a sloppy drawing of a couple of ‘maybe detours’...

[Guest_Oersted_*]

Possibly out on a limb here, but maybe Home Plate is the source of these thin layers of white material, perhaps salts, that we see just under the surface in the valley.

There's no distinct tail of white deposits downwind from Home Plate on the surface. This could be because such deposits are blanketed with darker sands from time to time during dust storms.

So, Home Plate could be the source of the white material to the surrounding lower areas. Home Plate itself is higher up, and therefore does not get covered in darker windblown deposits, which rather collect in the eolian cul-de-sacs.

Maybe Home Plate protrudes from the valley floor because it is made of a harder material than the surrounding areas. Would this fit together with Home Plate being white due to salts?

[Guest_RGClark_*]

I grabbed Alan's color version, did a judicious contrast stretch on the bright end (photoshop curves) and an edge sharpening on the brightness.  Brings out quite a bit of detail.

There was a salt-patch on the drive from Bonneville to the spur, about 2/3 or 3/4 of the drive, more in the vicinity of "pot of gold" rock, as well as the big patch found later.  Similar enhancements on all of them show quite a variety of color differences within the different high reflectance materials, but I can't easily find my old files, buried on non-connected hard drives and over 100 "misc' CD's.

Great image. Does the bluish rock near center/right look metallic to you?
It has the appearance of an iron-nickel meteorite.


- Bob Clark

[Bob Shaw]

Great image. Does the bluish rock near center/right look metallic to you?
It has the appearance of an iron-nickel meteorite.
    -  Bob Clark

Bob:

I see a vesicular basalt - it lacks the 'finger sculptured' quality of such a meteorite, nor is there any sign of a fusion crust, should it be a stoney-iron.

Presumably, however, deflation of the surface in areas subjected to regular wind patterns would tend to concentrate meteorites as the loess-like materilas get removed. For my money, as well as a backhoe, I want a magnet stuck on!

Bob Shaw

[mhoward]

Just because it's pretty:

[alan]

false color image of the other side

The reddish clump reminds me of material seen by opportunity at purgatory