Fossils, fossils and more fossils

Posted by on January 30, 2013 in Collecting, Fossils | 0 comments

I was thinking about doing a blog on several local fossil locations, but I was going to hold off on that until early spring.  However, one of our readers requested some information about fossil collecting and so here we go.  Fossil collecting is rather exciting.  Traveling to a fossil site you are full of anticipation, anxious to get out and hit some rocks and hoping, just hoping, to find something really cool!   Yes, it is cool when you hit the rock in the correct manner, it splits about in its layers and wow, there is a sea shell looking right back at you.  If you are lucky, you will even have two halves of the fossil – the cast and the mold and you can even put the rock back together like no one ever harmed it.  What I think is really neat other than finding something, is that you are the first person to ever see that fossil.  Certainly, since humans weren’t around when these organisms lived in the ocean, you are the first intelligent life to see the animal – period.

A group of fossil nuts collect at Swatara State Park.

A group of fossil nuts collect at Swatara State Park.

Much like mineral collecting, some of the sites are on private property.  By reading this blog doesn’t give you permission to access the land, but I have talked with two owners involved here and the last I knew, they did not mind fossil collectors tearing up their rocks.  Things do change over time and respect a owner’s wished should the area be closed to collectors.

Let’s start in York and Lancaster counties.  Unless you have done some reading of older geologic publications or visited a local museum that had a fossil display, you are probably not aware of many fossil sites right here under your feet.  The reason being is that most of our rocks in the southern half of YorkCounty and the southern two-thirds of Lancaster county are ancient rocks, reflecting a history that went back to 500-600 million years ago.  Yes, we were mostly under an ocean at that span of time.  According to the fossil record, life in the ocean was very sparse, not flourishing with many species.  Oddly enough, even with the limited species, one of the most complex organisms to live in prehistoric seas were trilobites.  Trilobites of the Cambrian age actually lived right here.  At least three species of trilobites have been identified from the York and Lancaster areas, mostly confined to a shale and limestone rock unit known as the Kinzer formation.  In fact, the NorthMuseum in Lancaster has specimens of trilobites collected from a site now destroyed that have only been found there.

Before, I give you several of my favorite sites for these ancient bottom dwellers and king of the ocean, one important fact.   As stated above, live was sparse and this means that finding a trilobite may be a long and patient task.  Don’t expect to find a trilobite in every rock or even two in one day.  But when you find a trilobite, it will be a find that you will not forget.  Going to my later several sites outside of southeastern Pennsylvania will be much more rewarding as those rocks are much younger and formed during a time that life in the ocean was near its peak.

Ollenelus trilobite found at Locust Lane

Ollenelus trilobite found at Locust Lane

For YorkCounty fossil seekers, the Locust Lane site has been the best recently exposed.  This roadcut is found in ManchesterTownship just west of Interstate 83.  In fact, there is a Locust Lane underpass on the interstate.  You may access Locust Lane either off the Susquehanna Trail or off of North George Street.  This shale outcrop has produced several specimens of Ollenelus trilobites.  Often times, seeing a fossil in “fresh” rock is difficult.  I once knew a collector who would go to a site, dig up some new rock and let it sit on the surface for several months to weather, which would allow the fossils to be more easily seen.  It was at the Locust Lane site where a gentleman was having a bad day and decided to take a walk to think about his problems.  He sat down on the concrete culvert at this site and while thinking, started to pick up pieces of rock and looking at them.  What did he expect to find, probably nothing, but it was the movement that helped to relax him.  Guess what?  In one of those pieces he found a trilobite (missing its trail and section of body) but it was well preserved.  Now talking about a change of luck, you can imagine his feelings then!!

The KInzer shale exposed at the Locust Lane site

The KInzer shale exposed at the Locust Lane site

Another roadcut site located in Manchester township is along Bull Road about 0.3 mile north of Greenbriar   Road.  Located on a curve of the road (use much caution here) is a small outcrop of the tan-to-light green shale.  Within this rock, small trilobites have been found and were thought that these were immature ones.  Don’t be surprised to find fragments of a trilobite likes heads or tails.  Often, you will find pieces of fossils rather than the complete animal.

One more site where I never had any luck but trilobites were found in the early 1900’s is in a rather long exposure of the Kinzer shale along North George Street between U.S. Rte. 30 and Interstate 83.  I stop here occasionally to examine rock that may have fallen down during the winter or after the spring thaw.  Maybe, just maybe I would strike it lucky one time to see a freshly exposed trilobite.

In LancasterCounty, the site of the MontessoriAcademy on Weaver   Road in ManheimTownship has yielded some nice fossils.  During the building of the school, fossils were collected and then presented to the academy for a showcase in their lobby.  A cultivated field located just to the north of the school, which they own, has yielded trilobites.  The best time to seek permission from the school would be during the non-productive period with the crops.  Even if not granted permission to collect, check out the showcase of fossils.

Many Cambrian sites in York and Lancaster counties have been  uncovered in the past 20 years with construction.  As rock is dug up by a contractor, especially in the area containing sedimentary rocks including the Kinzer formation, fossil collectors have found some niffy finds.  As with development, there sites are gone in matter of a short period of time.  It doesn’t hurt to keep your eyes open around such projects.

The Roth Road pit in 2010

The Roth Road pit in 2010

Perry County is one of the most fossiliferous areas in eastern Pennsylvania.  IT contains a number of rock formations within the Appalachian Mountains that were formed during the Devonian Period, when the sea life was nearly to its peak with species and abundance.  Chances are in many roadcuts or locations where the rock is being removed, you may find fossils.  One such locality that I have been using for an educational stop fro many years is located along Roth Road, about 0.75 mile south of New Bloomfield.  The side of the hill has been dug into removing shale and exposing a number of good fossil beds.    Depending upon how much material and how often the rock is being dug can vary.  Obviously, with more digging, it exposes new rocks for a collector to go through.  Watch this shale though, it is very fragile and can crumble in your hand easily.  It is better to bring home larger pieces and break them down into smaller specimens under a more controlled environment.  What is found here?  Greenops and Phacops (our state fossil) trilobites, a number of clam and brachiopod shells, coral, bryzoan, gastropod and crinoid stems.

A shell found at Swatara State Park, similar to what you will find in Perry County

A shell found at Swatara State Park, similar to what you will find in Perry County

The second site to bring to your attention is a rather new discovery.  Found in the same rock formation as the Roth Road site in PerryCounty, this site provides good collecting for the smaller children.  It is located about 2 miles west of Auburn, SchulykillCounty along Pa. Rte. 895.  SouthManheimTownship has developed a large area where shale was dug out of the hillside.  If you look in the rock piles close to their maintenance shed, you will find layers that are filled with assorted fossils and jumbled up.  Many of the fossils are broken and appear that the animals were tossed around in the ocean.  Shell fragments, many crinoids and bryzoan dominant this rock.   It reminds me of a low-tide line along the shore.  I have found some nice shells impressions in this area.

Bryzoan found near Auburn

Bryzoan found near Auburn

Crinoid stems and shell fragments from Auburn

Crinoid stems and shell fragments from Auburn

At first look up higher on the gentle slope of this shale pit, it appears there aren’t many fossils exposed.  I first thought that and suddenly I found a dark-gray hard shale containing rolled-up Phacops trilobites.  Wow, really interesting as this new color of the rock indicates a different environment than that rock found on the bottom.  Pay attention to the harder, darker shale, it contains trilobites that weren’t found in the low tidal rock.

Rounded-up Phacops trilobite - Pennsylvania's state fossil

Rounded-up Phacops trilobite – Pennsylvania’s state fossil

Where ever you go fossil collecting, take along a masons hammer with a chisel blade, a chisel for splitting the rock in the layers and possibly a mini sledge to break the larger rocks.  It is advisable to take a box or bucket and newspaper to wrap and pack your finds.  These will be the oldest antiques you will ever find – take care of them.

Coral fossil collected from Swatara State Park but similar specimens can be found in Perry and Schulykill counties

Coral fossil collected from Swatara State Park but similar specimens can be found in Perry and Schulykill counties

Leave a Comment

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>