Tag Archives: crinoids

A Geologic Tour

Dr. Jim Derby is a geologist who has taught at the University of Tulsa and worked in the petroleum industry. He knows a thing or two about rocks.

He gave me a tour of the geology around his house. The cool thing is you can find similar features in the rocks at your home…fossils, traces of long dead organisms, maybe even some dino droppings.

Fossils in your backyard

(a note from Dan- This has been updated with a  few changes from the original. Special thanks to Dr. Jim Derby for helping me clarify a few things.)

So you’re thinking, ‘Man, fossils are cool but I’ll never see them in Oklahoma.’ How about a fossil hunting trip to south Tulsa? Leake Park has dozens of gigantic stones that are used as barriers. Nearly everyone of them are home to roughly 300 million year old fossils. The rocks were once the bottom of an ancient seabed that covered Oklahoma from the Cambrian through the Devonian Period.

The fossils include Crinoids, an animal that attaches to the sea floor and filters food as it comes by. The Crinoid fossils are either small and round with a hole in the middle or you can see the stem.

Other fossils include ancient clams and Brachiopods. Brachiopods live on the seafloor. They kind of look like clams but they’re different animals. They use a stalk-like device to anchor themselves to the bottom of the ocean and just wait for food to float by (kind of like me when I’m watching football). The fossils at Leake Park are sea shells from ancient sea and they’re right here in our backyard!!! They’re not sexy like a T-Rex but I highly recommend a fossil hunting trip of your own, it’s a great and simple way to introduce kids to the wonders of fossils.

Rock barrier at Leake Park Top of rock covered with brachiopods More brachiopods DSC_0150