Showing posts with label Ledyard Shale. Show all posts
Showing posts with label Ledyard Shale. Show all posts

Sunday, August 18, 2013

Fossils from the Alden pyrite layer of the Ledyard shale

I had the chance to sample the Alden Pyrite bed, within the Ledyard shale of the Ludlowville formation, this past May in a stream bank near the town of Alden, NY. The Alden Pyrite bed is so named because it is a layer of shale that has a high proportion of the fossils replaced by pyrite and often encased within nodules of the same mineral. Karl Wilson has a nice page of what he's found in the Alden pyrite beds at his website. Here is some of what I found:

A partial Mucrospirifer


This is a pelecypod that is partially surrounded by pyrite as well as having the shell replaced. It's likely a Nuculites triqueter or Nuculoidea corbuliformis.




A Gastropod which could be of the Bembexia genus.


This was the prize of the trip for me. A nice large Tornoceras uniangulare fossil. This is a nice comparison piece those that I've found at Arkona.




Another brachiopod that was relatively abundant was Ambocoelia umbonata





Another small Pelecypod







The day I was at the creek there was another gentleman who was actively mining the layer. He found two Spyroceras fossils, one of which had a large nodule of pyrite at one end. The Ludlowville formation is middle Devonian in age (Givetian stage).