Episode 176 A notably red slab of rock with some even more notable features has been the target of intense investigation for the past two weeks. Now Perseverance has dug into it with its abrading tool and opened up a deeper level of intrigue.

  • @paulhammond5155OP
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    427 days ago

    I’m not a geologist, but from what I understand the red colour is a good indicator of iron and oxygen at the time the sediments were laid down.

    • @SpecialSetOfSieves
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      426 days ago

      I’m already committing the cardinal sin of discussing redox states on social media, Paul, so forgive me for adding this note:

      With all the groundwater that seemingly flowed within the rocks of this region, oxygen needn’t have been present at the time of deposition. Alteration/diagenesis seems to be pretty damned important here. (Further aside - non-geologists are always shocked to learn that oxygen is part of so many minerals and rocks to begin with. Maybe it’s easier to talk about free oxygen, the kind that isn’t already attached to the iron or magnesium of whatever…)

      • @paulhammond5155OP
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        426 days ago

        Love it when knowledgeable folk join the chat :) It takes these posts to a whole new level :)

        • @SpecialSetOfSieves
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          220 days ago

          Very late reply, Paul, hope you don’t mind:

          I’d love to contribute here a lot more - I’ve been planning to do so for a while now - but I tend to write very long-winded posts (see above, again) which maybe doesn’t work on social media, and I’m also not one-tenth the geologist Steve Ruff is. If you think my somewhat inexpert posts are OK, though, I’m happy to oblige when I actually manage to find the time.

          • @paulhammond5155OP
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            220 days ago

            I personally don’t care about long winded posts, I think you’ll find those that are seeking a deeper understanding will not care either. There will always be those who will want a TLDR post, but you can leave that to others to condense :)

            Look forward to your posts (whenever you have time) :)