Wednesday, April 28, 2010

Fossil Fun

I went for a walk along Lac Saint Louis yesterday, at the southwestern shore of Montreal. My primary purpose was bird watching, but I also found some great fossils.

There were some crinoids, bryozoans, brachiopods, and corals. Not sure of the age, still doing some investigating. Seems like Ordovician would be the earliest. I have read that there are Paleozoic fossil deposits in the canal nearby, so the time frame makes sense.

First up are what I believe to be some corals. While they existed in the Cambrian, fossil corals don't become common until the Ordovician.
Here are some crinoid stems (the round and star shape discs), as well as the edges of some brachiopod shells. Crinoids, also known as sea lilies, came about in the Ordovician, and are still alive today! Brachiopods also continue to thrive, after originating in the Cambrian. They were very abundant through history, but declined greatly after the Permian-Triassic extinction event.

I think the star shaped crinoid stems look rather like the little star noodles I ate as a child. Next up are some bryozoan colonies - these are also called "moss animals". They are so unique, they comprise their own phylum. They form spongy looking colonies, and when fossilized they look similar to coral. My geology class has caused me to become much more interested in rocks, and not just what may be hiding beneath them.

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