I went back to the East Bethany fossil site yesterday. I came home with about 20 pounds of rough rocks from the early Devonian and late Silurian periods. The East Bethany site is an abandoned railroad right of way that cut through a hill. The path goes right through the middle of the hill, so it’s very easy to move between geological periods. When I work the hill, I start near the top, which is well into the Devonian period. I cut a step into the hill to stand on, then dig a pit in front of me. There is about 12 inches of topsoil over the fossil bearing shales. Once I’ve collected some fossils from the first pit, I slide down the hill a bit, cut a new step, and use my old step as the start for a new pit. Repeating this all the way down the hill yields regular samples from several time periods.
Another good idea is to look through the tailings that other fossil hunters leave near their pits. These rocks might not have the specific fossils the other digger was looking for or they might have been encased in mud and needed some rain to clean them off. I’ve found a couple good fossils on the surface next to an old pit.
New York State is doing road work on the section of Route 20 that goes by the East Bethany site. https://www.nysdot.gov/projects has a couple projects listed for the Bethany/Batavia area. I had to take a very long detour to get there heading West on Route 20. I think the project is just getting started because I was able to take Route 20 Eastbound to get back home. Like everything else in that part of New York State, it’s always about a mile further than you thought it would be.
There are two hill faces that contain fossils at the site. The south face (facing North) is much wetter that the North face (facing South) The shale layers are very soft and fragile here. It’s easier to dig, but you have to take great care when removing slabs of rock or they will crumble. They become quite brittle after they dry. The North face (facing South) has a harder topsoil layer, and the shale layers are generally drier. It’s easier to pull a large slab out of this hill. About two thirds of the way up the hill, there is a marked transition and extinction layer. The deposit changes from a freshwater shale to a harder rock. Chert, I think. I think it happened in the Early Devonian period. I didn’t keep my samples separate enough to create a fine timeline. I’m going to bring several bags with me and keep each layer separate next time I go.