Eastern Oklahoma

[Fred Toast]

Found this imbedded in a rock and we’re trying to ID it.

It looked to us like the back of a crab.

It’s approx. 7 cm across.

Found in NE Oklahoma, near Tahlequah, high on hillside.

Does that make it Devonian period at the latest?

Please assist.

Edited December 25, 2019 by Fred Toast
More info

[Uncle Siphuncle]

Brachiopod, not crab.

[Fred Toast]

46 minutes ago, Uncle Siphuncle said:

Brachiopod, not crab.

Thank you!  Are we looking at the rear near where the pedicle would protrude?

Edited December 25, 2019 by Fred Toast

[Uncle Siphuncle]

7 hours ago, Fred Toast said:

Thank you!  Are we looking at the rear near where the pedicle would protrude?

Yes near hinge line.

[grandpa]

As to age, the eastern 1/4 of the state is mainly Penn age with some Miss exposure along the upper eastern edge of the state.  See below.

[Fred Toast]

20 hours ago, grandpa said:

As to age, the eastern 1/4 of the state is mainly Penn age with some Miss exposure along the upper eastern edge of the state.  See below.

Fantastic! Thank you! Do you know where I can find a more detailed map like this? “My” brachiopod was in the zone that’s either Pennsylvanian or Mississippian, based upon this map.

[Jackson g]

The rock looks consistent with Mississippian chert to me. The brachiopod is a steinkern, or the internal mold of the original shell.

[grandpa]

7 hours ago, Fred Toast said:

Do you know where I can find a more detailed map like this

Try:  https://catalog.data.gov/dataset/a-digital-geologic-map-database-for-the-state-of-oklahoma-ngmdb