1.4 billion year old microbial mats (black wrinkles) in volcaniclastic claystone (green-grey layers)
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Пікірлер: 3
@cfmcguire2 жыл бұрын
How do these compare to the Belt Supergroup sediments, which are of similar age?
@geologyjohnson7700
2 жыл бұрын
Very similar. The biggest differences are that the Belt is mostly interpreted as fresh water, whereas the Roper is interpreted as marine. There are also a lot more carbonates in the Belt were as the carbonates are rare in the Roper. Abbott and Sweet (2000) do a good summary of the upper Roper Group in their paper. Having said that, I am starting to find evidence that the Roper may not have been fully marine, at least all the time.
Пікірлер: 3
How do these compare to the Belt Supergroup sediments, which are of similar age?
@geologyjohnson7700
2 жыл бұрын
Very similar. The biggest differences are that the Belt is mostly interpreted as fresh water, whereas the Roper is interpreted as marine. There are also a lot more carbonates in the Belt were as the carbonates are rare in the Roper. Abbott and Sweet (2000) do a good summary of the upper Roper Group in their paper. Having said that, I am starting to find evidence that the Roper may not have been fully marine, at least all the time.