The Top of Vera Rubin Ridge Part 2, Site 67-73, sol 1944-2297, 24 Jan 2018-22 Jan 2019 Options

[neo56]

I doubt 40 days is enough time to form a photooxidation rind (we were talking a year or two), but seeing the uniform color changes in that blink comparison brought the conversation back to mind. It could be a good opportunity to check!

Don't you think that atmospheric dust deposition will hide the signal of surface oxidation?

[PaulH51]

'Grange': Focus merge product, rotated sharpened and cropped estimated scale added (based on diameter of Inverness)


Raw file Link

[nprev]

Extraordinary. Anxious to hear the geologists' take on this.

To my unskilled eyes this looks less like a water-borne mineral intrusion than a melt of some sort enriched with whatever mineral those inclusions are made of. Looks like it once was very, very hot.

[paraisosdelsiste...]

Extraordinary. Anxious to hear the geologists' take on this.

To my unskilled eyes this looks less like a water-borne mineral intrusion than a melt of some sort enriched with whatever mineral those inclusions are made of. Looks like it once was very, very hot.

I think we are seeing a calcium sulphate with some metallic oxides (maybe iron or manganese) carried by the water that was reacting with the rock. But it is great to see this texture, I don't see it very often on Earth!

[PaulH51]

Looks like a short drive to the south on sol 2218 NLA. May have terminated early?

[RoverDriver]

From a cursory look, it seems all went well. About 5 meters worth. It was just a checkout drive, not a full drive.

Paolo

[jccwrt]

Don't you think that atmospheric dust deposition will hide the signal of surface oxidation?

It'll certainly contribute to the observed passive spectra. However, we know the spectral signature of dust, so it might be possible to subtract out that signal to look for changes in the underlying rock if it doesn't totally coat the surface. AFAIK this is an ideal use case for VNIR spectral mixing models, since we have the rover nearby to help place constraints on some of the input parameters.

I'm not sure that we're actually capable of detecting that signal, but it would be useful and interesting to look for.

[serpens]

The Curiosity Mission Update of 1st November identified "Grange" as a workspace target stating: "Grange" appears to be an area of bright calcium sulfate (commonly observed as veins cross-cutting bedrock encountered throughout the mission), but with small, dark inclusions that might have an interesting composition.

[jvandriel]

The Navcam L view on Sol 2218.

Jan van Driel

[Phil Stooke]

Thanks, Jan. Here is a circular version of it. Compare the outcrops in the lower right area to the same areas in the previous circular panoramas to see how we moved.

Phil

[PaulH51]

An unprocessed focus merged MAHLI product of what may be the target called 'Lossiemouth' the base images were acquired before the drive on sol 2218. It appears to show some of those erosion resistant dark inclusions in the bedrock and the mineral filled fractures similar to those that were seen in 'Grange'.
Interesting geology on this ridge for sure

[HSchirmer]

An unprocessed focus merged MAHLI product of what may be the target called 'Lossiemouth' ...
It appears to show some of those erosion resistant dark inclusions in the bedrock and the mineral filled fractures similar to those that were seen in 'Grange'.
Interesting geology on this ridge for sure

That appears to be some very fine-grained matrix rock,
What "unit" are they calling this?
We've heard of "mud stone" is there any prediction about aeolian dsposits; "dust stone"?

Curious that similar rock seems to occur as oxidized red and reduced blue forms

[jccwrt]

That appears to be some very fine-grained matrix rock,
What "unit" are they calling this?
We've heard of "mud stone" is there any prediction about aeolian dsposits; "dust stone"?

Curious that similar rock seems to occur as oxidized red and reduced blue forms

Curiosity is still in the Murray fm (upper Vera Rubin Ridge aka Jura mbr.) which is still a mudstone, but with odd highly oxidized patches. Last I heard (a few months ago), the interpretation was some odd diagenetic event taking place within this section of the Murray.

As for dust stones, check out Nathan Bridges' work on Martian aeolian deposits ("Duststones on Mars" is a good primer). Given that we're still apparently in a lacustrine setting, I don't think dustfall would be a significant input or even distinguishable from the surrounding lake muds. That said, dust stone deposits might become more common further up the mountain, and my understanding is that the very top unit of Mt. Sharp (the "Upper Yardang Unit") is thought to be a dust stone of some sort.

[PaulH51]

Looks like Curi made a 'Bump' to Lake Orcadie on Sol 2222, fingers crossed for a drill friendly piece but representative sample of the Jura member

[serpens]

Does anyone happen to know the criteria used to differentiate between the 3 Vera Rubin Ridge members?