Ordovician bioclaustration project begins

March 10th, 2014

Bellevue outcrop 031014FLORENCE, KENTUCKY–Today it was William Harrison’s turn to collect specimens for his Independent Study project. He’ll be working a full year on what he’s putting in these bags before he turns in his thesis. William’s project is an interpretation of the processes that led to bioclaustration pits in Upper Ordovician bryozoans, along with larger questions of bioerosion of trepostome bryozoans. We found some gorgeous specimens at the outcrop above.

William is collecting from what used to be called the Bellevue Limestone, a Maysvillian unit between the Fairmount and Corryville Formations. Now it is best known as the lower part of the Grant Lake Formation. The rocks represent shallow water deposits, much like the Whitewater Formation Coleman was working in yesterday, so it is loaded with eroded and encrusted brachiopods and bryozoans. This is Locality C/W-152 in our system along the Idlewild Bypass (KY-8) in Boone County, Kentucky (N 39.081120°, W 84.792434°).

William 031014William was particularly adept at finding large bryozoan zoaria (colonies), most of which were riddled with borings. He is here holding a specimen that in life would have been erect on the sea floor like a fan with feeding zooids on each side. You may be able to make out the many little bumps or monticules on its surface.

Guess who our neighbor was during our exploration of this outcrop?

Creation Museum 031014Yes, the irony is deep. “Billions of dead things” indeed, Mr. Ham!

Later that day we collected a few bored and bioclaustrating bryozoans from an exposure of the Kope Formation at Orphanage Road to the east (N 39.02984°, W 84.54121°). We have plenty of specimens to keep both William and Coleman busy, and already some ideas for poster presentations.

Just to show the human effect of sampling and collecting, our first stop of the day was entirely unsuccessful. We visited one of my first localities, an exposure of the Kope Formation at the confluence of the Ohio River and Gunpowder Creek in Boone County, Kentucky (C/W-7; N 38.90428°, W 84.79779°). It was here in 1984 that my wife Gloria and I found hundreds of fantastic encrusted cobbles, many with gorgeous edrioasteroids and thick accumulations of bryozoans. These were for a very brief moment famous in the local collecting community. Within a few months they were all gone. William and I were there now 30 years later hoping a new cobble or two might have eroded out, but we found nothing. A future researcher would have no idea such cobbles were present, except for the one paper in the literature.

 

Trackback URI | Comments RSS

Leave a Reply