This first photo is a collection of crinoid stems in a piece of weathered Redwall Limestone. The crinoid heads are missing, but the stems are nicely preserved because of their calcium carbonate pieces. those guys are about 335 million years old. The limestone that they are found in is one of the larger rock layers found at the Grand Canyon.
This next photo is a storm segment from the Naco formation. There are a least 3 different types of fossils in this piece. Can you find them? The twig looking ones are fossilized bryozoan, a moss-like creature. There are also crinoid stem segments, and a couple of clam-like shells
This picture shows an assortment of other fossils also from the Naco formation. There are (from left to right) a couple of clam-like fossils, crinoid stem segments, saved entirely in 3D (the little barrel shaped guys), a streched spiral gastropod (found in the Upper Iowa River neah Decorah, IA), and a few intact brachiopods. The difference between the brachiopods and the clam like ones is that the clam like ones (they have a technical name but i cant seem to remember what it is) are symmetrical through the suture, and the brachiopods' symmetry is perpendicular to the suture line. Here is a close up of the clam like ones...
3 comments:
Yeah! Thanks Rob!! Those are pretty cool! Shellfish fossils in Arizona - that's just plain cool. Have you ever found ones with critters in them other than shellfish? I saw one once with a crablike critter with legs and everything... its was really cool looking. Sounds like you were collecting even back on your mission. See! You knew where you were headed even then.
Thanks for posting your collection. Very cool stuff!!!
Rob,
I don't claim to understand everything you post, but I do find it absolutely fascinating. I missed the last couple of posts so I just caught up on everything. Fossils are pretty cool. When we lived in NC you could find fossils on the unimproved roads. To maintain the roads they dump marle (not sure of the spelling) on the roads which is crushed up rocks form the ocean I think. Anyway you could pick up some of the larger pieces and find all sorts of shells fossilized in it. Not really particularly old though, I don't think. Keep up the good work-I do enjoy your posts.
Love ya-Dad
Dad pointed out that I hadn't commented on this site...I admit that the last time I looked was when you first opened it up and then once or twice afterwards but didn't see any new posts so.....I had a lot of catching up to do! I commented on an earlier post tonight and then caught up with reading the rest. The photos are great and it is amazing that so much can be learned about the activity millions of years ago by looking at rocks we usually just glance at on our way somewhere else. Very interesting.
Mom B
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