Tuesday, March 30, 2010

West Virginia Brachiopods

These pictures of brachiopod fossils are from the West Virginia-Virginia border off I-64 exit 183? (Monroe County, WV). They were sent to me by a reader named David who was wondering about their identification. He writes they are similar to fossils he find in the Ordovician formations of Craig County, Virginia. If any one knows of what they might be, please post a comment.

The 2nd and 3rd images remind me of muscle scars on the inside of a brachiopod shell.  The fourth imprint looks like a Hebertella.





5 comments:

Shamalama said...

Hmmm. hard to nail down the location with the vauge info he gave you, so I'm not sure of the age, but I think they are late Silurian to Devonian fossils. The first and fourth looks like Atrypa sp. Second and third look like Productella. Not sure what the last one is.

Anonymous said...

According to a geological map of WV (available here: http://www.wvgs.wvnet.edu/www/maps/maps.htm), most of Monroe Co. WV is underlain by Mississippian rocks, which fits with my (and Shamalama's) identification of the second and third photos as productid brachiopods. The little elongate dimples (or bumps) all over the shell surface are spine bases, and these are very characteristic of some of the productid brachs, which are common in Mississippian rocks (even here in the Alberta Rockies).

Cheers,
--Howard

Michael Popp said...

Thanks Shamalama and Howard for the identifications and site info. I was wondering if the last brachiopod picture might be from the Mississippian period. It looks like a brachiopod found in area within sight of metro-Louisville called Floyd Knobs and the hills that stretch out to Borden, Indiana. The fossil might be called Orthotetes keokuk (click link to see specimen at Indiana State Museum).

Shamalama said...

Howard, I agree that most of the county where the fossils are found is underlain by Mississippian rocks, the area that the fossils were found in (Border of VA/WV) is Devonian in age, specifically the Chemung Group. After further research I think the first and fourth are Spinatrypa but stand by the Productella ID for the second and third.

Unknown said...

Thanks for your help everyone. I should have been more specific about location, which was Greenbriar Co, WV. Based on the WV geological map mentioned in Anonymous's post, these are Devonian formations.

David