The Top of Vera Rubin Ridge Part 1, Site 66-67, sol 1812-1943, 11 Sep 2017-23 Jan 2018 Options

[PaulH51]

Curiosity's weekend workspace L-MastCam, raw in MS ICE. Also a rather nice cropped ChemCam RMI target that features in the workspace. sadly no target names (yet)

[Ant103]

Hi everyone

Found some motivation to do some work there. So, a little bunch of panoramic of my own

Sol 1866 Mastcam34



Sol 1867 Navcam



Sol 1869 Navcam



Sol 1871 Navcam



And an extra postcard, from Sol 1866, by Mastcam100 :



Enjoy

[climber]

C'est la cas!
Merci Damia

[jvandriel]

The Navcam L view on Sol 1873.

Jan van Driel

[PaulH51]

Possible aborted drive on 1873, very small move, nothing obvious in the workspace that would warrant a short bump, but what do I know

[Ant103]

Sol 1873 Navcam panoramic :

[HSchirmer]

"But, if you don't drill actual bedrock, how would you know it's the same geologic unit?"

All the ChemCam and APXS data, plus geological interpretation of HiRISE and rover images.
...
Phil

Good point.

But, eh, I guess I should have phrased my question differently....

What if Vera Ruben Ridge was influenced by groundwater from a deep fault

https://www.lpi.usra.edu/meetings/lpsc2013/pdf/3106.pdf

would we be able to identify vertical displacement?

Lots of sedimentary basins on Earth have developed deep faults that create paths for groundwater flow-


Would there any way to determine whether the geological unit NORTH of the Vera Rubin Ridge has moved higher or lower
than the same geological unit SOUTH of Vera Rubin Ridge?

[Phil Stooke]

So the first step would need to be detailed geological mapping using HiRISE images and the CRISM compositional data. Is there much evidence of faulting? Not sure, but it could be looked for. My impression is that there has not been a huge amount of faulting, so I would not be expecting an explanation based on large vertical motions. But I haven't done that work myself. Part of the reason for all the Mastcam imaging of the ridge along its northern side was to map the stratigraphy and structure. That can continue to the south as well. Wil there be evidence of vertical offsets? Or is it all stratigraphy, layer after layer without much faulting? I don't know, but that's how it could be tackled.

Phil

[HSchirmer]

So the first step would need to be detailed geological mapping using HiRISE images and the CRISM com positional data. Is there much evidence of faulting? Not sure, but it could be looked for. My impression is that there has not been a huge amount of faulting, so I would not be expecting an explanation based on large vertical motions. But I haven't done that work myself. Part of the reason for all the Mastcam imaging of the ridge along its northern side was to map the stratigraphy and structure. That can continue to the south as well. Will there be evidence of vertical offsets? Or is it all stratigraphy, layer after layer without much faulting? I don't know, but that's how it could be tackled.

Phil

Well, reason I'm asking, what may be dumb questions.

Given the amount of boxwork exposed not that far away- at Naukluft plateau, and at the base of Mount Sharp

and given estimates that boxwork features are likely due to groundwater,
and given estimates that cubic kilometers of groundwater are needed to create the boxwork features
https://thesis.library.caltech.edu/9838/1/S...chapters1-3.pdf

Then it might be interesting to look at layering, not just "It's sandstone" or "it's mudstone" but which lake layer are we talking about?

Idea being, that identification of specific lake layers, allows you to identify offset faults, and identify discontinuities.

Now, that's a HUGE challenge to put on somebody else, doing high resolution stratigraphapy takes huge amounts of data.

I'm just a bit curious whether the huge amounts of data being collected could eventually identify likely groundwater sources.-
"oh, there's a fault here, we see that the layers are offset by (1, 10, 100, 1000 meters) which suggests that there's a connection
to groundwater going down at least (1, 10, 100, 1000 meters)...

[RoverDriver]

Possible aborted drive on 1873, very small move, nothing obvious in the workspace that would warrant a short bump, but what do I know

The drive was intentionally short. Some targets were out of reach and on the previous drive we did not want to overshoot. While our cameras are well calibrated one has to account for some measurement errors!

Paolo

[PaulH51]

The drive was intentionally short. Some targets were out of reach and on the previous drive we did not want to overshoot. While our cameras are well calibrated one has to account for some measurement errors!

Many thanks Paolo, also the weekend plan just got released and it mentioned the 'bump'

[charborob]

Sol 1873 Lmastcam:

[RoverDriver]

Many thanks Paolo, also the weekend plan just got released and it mentioned the 'bump'

One would think there's a uniform understanding of what constitutes as a "bump". I have seen a 20-30m drive referred to as a bump. I end up calling anything that is less than a meter a "burp" since that typically requires only one or two rover steps.

Paolo

[Gerald]

...and given estimates that boxwork features are likely due to groundwater ...

Tafoni and honeycomb weathering as examples of salt weathering are other options, Given the sulfate-rich overlying layers, I'd consider some kind of salt weathering as another, if not more plausible, cause of the boxwork. This doesn't rule out additional groundwater activity, but it may be less evident, at least from a distance.

[serpens]

The boxwork is on the horizon between the sulphate rich upper member of the Mount Sharp lower formation and the overlying aeolian deposits. There would almost certainly have been a hiatus following the final water influenced deposition so dessication fracturing must be a contender and given the lack of lithification of the overlying deposits any subsequent groundwater interaction must have occurred before the aeolian deposition.