Anyone ever hunted the Shawangunk formation

[Noel]

Looking into going up to the Shawangunk formation near the Delaware River gap, looking for any fossils but would most like to find a eurypterid. My problem is I can’t find exactly where the fossiliferous parts are. I know it’s a long shot but has anyone hunted this formation before.

[grandpa]

Welcome to TFF from Austin, Tx.  Sorry I have not hunted this area, but wanted to extend a welcome.

[erose]

So many moons ago my wife and I had a cabin in Cragsmoor, NY on the Shawangunk ridge. This is further north than the water gap but still very similar geology.  The vast majority of the Shawangunk Formation is quartz conglomerate and devoid of fossils. I believe the thinking is it is the remains of braided streams washing down off of whatever mountains were nearby during that particular Appalachian orogeny. This was during the Silurian Period.  In amongst the thick layers of conglomerate and sandstone are some dark shales. But these are layers measured in a few centimeters amongst tens of meters of fossil free matrix.  The Shawangunk eurypterids were found way back in the early part of the 20th century in those black shales near Otisville, NY where the railroad was quarrying the conglomerate for track ballast.  I visited what remained of the quarry in the mid 1990's. It was an overgrown site used by the locals for shooting guns and drinking beer.  I was able to find a few minor exposures of the shale I could dig into and I did indeed find some scraps of eurypterids. But that stuff was nothing like what we know of euryptyerids from place like Passage Gulf, Lang's Quarry or Buffalo.  As mentioned in an earlier post the quarry was eventually developed as a home site and is no longer accessible for collecting.  In addition most of the Shawangunk ridge is now state park or preserve and collecting would be verbotten.  BUT it is some of the most interesting natural landscape you can explore in that region.   Not trying to discourage you from the gunks, but don't expect much in the way of fossils in that rock.  Instead look into the Devonian aged stratigraphy near there. I have collected cool Lower Devonian stuff near Montague and Middle Devonian fossils as well near Bushkill.  Gets some geo maps and do some more homework and you will find plenty.

[Noel]

14 minutes ago, erose said:

So many moons ago my wife and I had a cabin in Cragsmoor, NY on the Shawangunk ridge. This is further north than the water gap but still very similar geology.  The vast majority of the Shawangunk Formation is quartz conglomerate and devoid of fossils. I believe the thinking is it is the remains of braided streams washing down off of whatever mountains were nearby during that particular Appalachian orogeny. This was during the Silurian Period.  In amongst the thick layers of conglomerate and sandstone are some dark shales. But these are layers measured in a few centimeters amongst tens of meters of fossil free matrix.  The Shawangunk eurypterids were found way back in the early part of the 20th century in those black shales near Otisville, NY where the railroad was quarrying the conglomerate for track ballast.  I visited what remained of the quarry in the mid 1990's. It was an overgrown site used by the locals for shooting guns and drinking beer.  I was able to find a few minor exposures of the shale I could dig into and I did indeed find some scraps of eurypterids. But that stuff was nothing like what we know of euryptyerids from place like Passage Gulf, Lang's Quarry or Buffalo.  As mentioned in an earlier post the quarry was eventually developed as a home site and is no longer accessible for collecting.  In addition most of the Shawangunk ridge is now state park or preserve and collecting would be verbotten.  BUT it is some of the most interesting natural landscape you can explore in that region.   Not trying to discourage you from the gunks, but don't expect much in the way of fossils in that rock.  Instead look into the Devonian aged stratigraphy near there. I have collected cool Lower Devonian stuff near Montague and Middle Devonian fossils as well near Bushkill.  Gets some geo maps and do some more homework and you will find plenty.

Disappointing but I’m glad I didn’t waste a trip, 

 

thanks.

[Jeffrey P]

I wrote a hiking and bicycling guide to Shawangunk Ridge (the New York Section) which was published back in 2003. The ridge extends down into New Jersey where it is called the Kittatinnies and then through the Delaware Water Gap down into Central Pennsylvania. Geology is essentially the same. The bedrock which comprises the top of the ridge is quartzite conglomerate, generally unfossiliferous. A local paleontologist  told me that ichnofossils of worms have been found there, but other than those very thin black shale layers that occur sometimes between layers of the conglomerate from which eurypterids used to be found I haven't heard of any other fossils. Glacial erratics that can be found commonly throughout the Ridge sometimes bear Devonian fossils from up north. Everything I've heard confirms that those eurypterid beds are unfortunately no longer accessible.  Erose mentioned that some of the fossil layers both east and west of the Ridge are fossil bearing. Among those are the Ordovician Martinsburg Shale which does have marine fossils in places, mostly brachs, but also occasionally trilobites.  I even did hear once of a eurypterid being found there. Good luck and get ready to do plenty of research if you're intent on collecting in this area.

 

erose is right about the natural landscape of the Ridge have interesting, unique, and amazing features, certainly worth visiting.  Used to be my main haunt. 

[fossilcrazy]

I have hunted parts of the Shawangunk near Otisville,NY. The only fossils I found were Silurian fish scales in red shale. Neat finds, but no head shields or Eurypterids.