Of all the subjects in sedimentology, this is the one where I've found it hardest to get any solid information, especially such as might be suited for beginners.
I hope that you don't think that I'm just asking you to do my homework for me, I've been googling around this subject literally for weeks. And yet some things are still slightly beyond my grasp.
Let's start with a (hopefully) easy question (I shall number them for your convenience, this is number 1).
(1) When I first came across the term "radiolarian chert" I supposed that it was a term analogous to "oolitic limestone": i.e. the word
radiolarian meant that in thin section one could see that it was composed of radiolarians. But I haven't found anyone saying so directly.
Gradually, by observing usage, I came to suspect that I was putting the emphasis in the wrong place and that the word
chert implied that sufficient recrystalization had taken place that no radiolarian structures were to be seen any more; and that the radiolarian origin was a matter of inference rather than observation. But I can't find anyone directly stating that either.
All anyone tells me is that it's chert of radiolarian origins, but
not how it is so identified.
I could make similar remarks about diatomaceous chert (mutatis mutandis).
Can anyone help me with this? Thank you.
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