South from the landing site, sols 72-237, Starting the science traverse Options

[Phil Stooke]

It's not easy to figure out where to divide threads, but we just had a drive on sol 72 which I think we could say signifies the beginning of the traverse to the south and the start of regular science operations. Originally I expected a clean break with helicopter operations but we are not getting such an obvious dividing point.
So I am taking it on myself to start a new thread for the exploration mission. If the timing seems wrong people can let me know.
Phil

[serpens]

I thought the same. Also a hint of soft sediment deformation on the middle left - maybe perhaps.

[tdemko]

I thought the same. Also a hint of soft sediment deformation on the middle left - maybe perhaps.

I see the bed boundaries, which may be defined by a finer-grained drape, fairly well expressed. Some other images even looked like there may have been some ripples preserved there. On the whole, it looks like cm-dm scale beds, with some vertical surfaces expressing the bed boundaries and others completely obscuring them.I've been fooled by some of these exposures into thinking the beds were more homogenous and thicker, but tracing them laterally, I could see the cm-dm spacing of internal bed boundaries. I do see the areas that you and Bill are talking about, which stick out because they are different from the thin/tabular bedding that's pervasive.

I'm sticking with my subaqueous sediment gravity flow/turbidite interpretation until I see something inconsistent.

[serpens]

.....I'm sticking with my subaqueous sediment gravity flow/turbidite interpretation until I see something inconsistent.

Just for clarity Tim. You previously mentioned the delta front for gravity flow/turbide deposition. While these rocks tend to have moved around somewhat, given the apparent lack of dip, do you mean the delta toe? Apologies if I'm missing something obvious.

[tdemko]

Just for clarity Tim. You previously mentioned the delta front for gravity flow/turbide deposition. While these rocks tend to have moved around somewhat, given the apparent lack of dip, do you mean the delta toe? Apologies if I'm missing something obvious.

No, I think you are more correct here. We've seen some of the later foreset successions in the cliff faces. If these beds are what I think they are, the subaqueous sediment gravity flows would have originated either as collapse of the mouthbars or lip of the delta, and then flowed down the foreset/delta front, to the toeset, and potentially out onto the lake floor. If the river inflow was dense enough, hyperpyncnal underflows (which are also sediment gravity flows) could also have generated similar deposits. The thin-bedded nature of the outcrops in question look to me like either toesets or parts of fans that would have been deposited outboard of the foreset/toeset strata.