Microbial Horizon

Perhaps this is a rather weird thing to submit and many will ask what this is Well, this is a thin section of a rock, which means the rock was cut in very thin slices. Thin enough to make light (of the microscope) shine through it. the thin section is 1cm wide.

This is a limestone made of several calcareous shells and other animal products from the Uppermost Cretaceous. I will spare you from more scientific terms and try to give only a brief explanation . I wrote my diploma thesis based on these samples and don't want to echo that again .

So, what can we see here?
On the bottom left is this round structure, that is a cross section of a worm tube. Around and inside of it are many puny, dark spots and those are pellets. Those pellets are most likely fossilized poop of worms and other marine animals
On top are far less to no pellets but larger structures seperated by a darker sheet which is caused by microbes. The 'holey' stuff are mostly briozoans. Darker round things are koralline red algae, UFO-shaped lences are benthic foraminifers and lighter grey objects are echinoids (see orchins and alike).

Any use of this picture only with my permission.

Further thins sections can be found here:
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