Cessna Fossils

North of Bedford, PA is the small town of Cessna and nearby are some old gravel pits that were once excavated for Iron Ore in the 1800's. The limestones of this region are part of the Clinton Group and contain a very low percentage of Iron that formed as a precipitate in the form of oolites. As a result these deposits were mined for the Iron content but only at surface level as there the limestone had dissolved away enough to concentrate the Iron more.

A number of years ago my Father and I visited one of these old pits on a fossil expedition. The limestones have profuse amounts of fossils, some of which are replaced entirely by Hematite (an oxide mineral of iron). We were following the directions given us in the book "Fossil Collecting in Pennsylvania" and I don't recall finding the actual pit but I did find some chunks of rock that were eroding out of a shallow road cut in the area.

A chunk of rock with some Bryozoan or Coral fossils:



Side view of a rock with a Coral/Bryozoan in cross section:


A large Cornulites (?) tube and a Trilobite pygidium:



Protoleptostrophia


The book said that the rock layers were likely from the Rose Hill formation which is one of the few fossiliferous Silurian aged formations in Pennsylvania. The Rose hill is early Silurian and I think falls into the Llandovery series (443-428 mya).

While I didn't find a whole lot of specimens to bring home, the above few have lasted in my collection. I think I will take a trip out there this winter and try to locate the site again. Maybe I'll have better luck this time!

More Green River

In a previous post I mentioned how my Grandparents carted me all over Colorado to look for fossils and minerals. One of the places they took me was to Grand Junction so that I could explore the Parachute Creek member of the Green River formation. One of the best known localities to access this member is at Douglass Pass which is about 40 miles north as the crow files from Grand Junction, CO. Once you reach the pass you still have another 5 miles of dirt and gravel road to drive to get to an FAA Radar Dome where the rock layer is exposed on the side of a mountain. On the way up the gravel road you pass by many exposed layers of rock which are part of the Green River formation but are not the most productive layers. Since the Green River formation is a lake deposit you get different characteristics of rocks depending on how big the lake was at the time and the environment. My grandparents patiently stopped and waited at one of these road cuts as I scrambled up and down the slope looking for fossils and amazingly I actually found some:




A thin, sandy horizon of rock had fallen from some part of the cut and it had some fossil fish scales and bones on it. Below is a fish vertebrate (I think) and some scales that were on one piece of rock.




I don't know what kind of fish these fossil are from but the age is Eocene and must have been in a shallow deltaic environment for the sandy rock layer to form. I've been back several times in recent years but have not been able to locate any more pieces like those shown above nor the layer that produced them.

First trip to Green River

I’ve been fortunate that my Mother’s parents lived in Boulder, Colorado as I has allowed me many opportunities to visit them and also get some mineral and fossil collecting done. During a trip in 1996 they drove me all over the state to look for stuff including to Florissant, CO for fossils and a Topaz mine, Grand Junction, CO to the Parachute Creek shale and clear up to Kemmerer for fish fossils in the Green River formation. This was to be my first trip to the Kemmerer and I’d picked one of the many quarries that were advertised in “Rock and Gem” magazine to go visit. I really wish I could remember which one I went to but all I remember is the long drive back to the quarry on a badly rutted dirt road. My Grandfather was driving and we were riding in a regular car that did not have much clearance. I distinctly recall hearing the bottom of the car scrape the tops of some of the higher bumps along the way but we made it without incident.

There were a half dozen other people there waiting for the quarry to open which it did shortly after we arrived. The quarry foreman explained what to do and where to go and I eagerly set to work picking a nice area where the rock seemed to be jutting out from a low wall. I don’t have many pictures of the quarry itself as this was back before digital cameras were cheap so all I had was a film camera. The best picture I have is this one of my Grandfather watching me try to split a slab.



He was a great guy who wanted to see his grandson find some good fossil fish and made sure that anything I did find was moved out of the working area while giving advice on where to split. The trip was in late September so the weather was not particularly warm as you can see by our clothes.

I had visions in my head of large pristine fossil fish with every blow of the hammer and scan of the subsequent splits. The quarry foreman had explained the concept of the “split fish” layer to me but it took a couple of fish finds for me to understand exactly what he meant. The “split fish” layer is self descriptive in that the fossils will split with the layers of rock so that you often get a little bit of a whole fish on the facing sides of a split slab. You can see an example of what I mean below:





After four hours of me splitting and my grandparents watching admiringly our time was up. I had found a number of Knightia and Diplomystus and I’d nicknamed the strata we were splitting as the “Explodofish” layers since so many of the fish I’d found showed evidence of post mortem gas expulsions with scattered scales or bones.




I did find two partial Priscacara and the first would have been very large but I only found half of it in many pieces.



The other was a whole fish but didn’t split well so that I have some bones but the rest is just impression. It’s too bad I didn’t know about how this specimen could have been salvaged by gluing the covering split back in place and then prepping the fish through the rock so that it appeared whole.




I also found some Phareodus scales and a partial jaw with teeth.



That evening we stayed at a local motel which was an adventure in and of itself. We checked in and went to our room where the door was already hanging open a little. After checking to make sure no one was in there and they motel had not double booked the room we entered into what we could only call a decorating nightmare. The walls and ceiling were painted white except for one wall which was dark purple. Before the paint had dried the workers had apparently sprayed glitter all over the place. The toilet had a constant drip and there was a hole in the floor near the base. To top it all off there was a velvet painting of the Virgin Mary above one of the beds. We were all grateful that the lights indeed turned off as we didn’t have to stare at the décor anymore and we checked out first thing the next morning. All in all it was a great trip and I enjoyed spending time with my grandparents.

A last couple of specimens that I've kept more for the memories than for the quality.

My First Fossils

It's neat sometimes to go through your boxes of findings and remember how and where you found each item. Many of you probably got started collecting fossils as a kid when you picked up a piece of rock with a shell or coral preserved within. My first fossil was found at a rock show in California that my Mom took me to. I was five or six years old at the time and my older sister had visited it during a school trip. My sister wanted to go back and Mom thought it would be a nice family trip.

This was my first rock show and I don't have too many memories of the experience but some few did impress upon my formative brain and I still recall to this day. I wandered around the large hall looking at the various rocks, minerals and fossils that were on display. I recall a bucket of "pick your own" geodes in one corner next to a rock saw along with plenty of lapidary rough and slabs. I only had a few meager dollars with me and my purchases were a piece of Cinnabar, a small 1" x 1/2" slab of Turritella agate with a whole snail in cross section and four Brachiopod shells. I still have all of them in my collection somewhere, but I came across the four original Brachiopod shells while sorting through my Devonian boxes:



The fossils are Strophodonta from the Devonian (Givetian) aged rocks of the Silica shale in Sylvania, Ohio. You can see the (now worn) card that came with them is still intact and a great memory to have as well. These are very common fossils in the formation and are still found today at shows in give away bags and inexpensive fossil bins. Here you can see the inside of the card that came with the fossils:




Notice that the card was originally meant for some Paraspirifer fossils. The seller crossed the name out but never put the Strophodonta name in it's place. It's an innocent thing that any of us do when giving a fossil to a child. You can't know if they will care what the fossil is once it leaves your booth or they might loose the label later anyway. It wasn't until many years later, as I was looking through fossil web sites and books, that I recognized the fossils for what they were. I came full circle in 2007 when I took a trip through Ohio and down to Cincinnati. I made a stop in Sylvania and had the opportunity to collect from the Silica shale dumps at a quarry. I picked up a lot of Strophodonta shells then along with many other species, but the first four I got as a child remain one of my favorite fossils.