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Cover Photo:  Carrie Wivell Wolf and Jonathan Wolf’s son, Jackson, grandson of Phil and Shelly Wivell, celebrates his first Halloween!

Fossil Collecting in Maryland

Part 2: West of Frederick

by Richard D. L. Fulton

For hundreds of millions of years, the land that Maryland presently resides upon had rested predominantly at the bottom of the ancient oceans.

Around 335 million years ago, two continental plates—one referred to as the African Plate and the other known as the North American Plate—began to move toward one another, such as an irresistible force colliding with an immovable object, on a vastly grand scale.

The collision of the two continental plates was so violent that not only did their convergence form a new continent, which geologists have dubbed “Pangaea,” but as the North American Plate actually buckled from being rammed by the African Plate, the Appalachian Mountains were then created, which initially had been as high as the modern-day Himalayan Mountains as the result.

The ancient sea beds that would become, in part, Maryland, were then forced upward as a result of this continental collision, thereby becoming incorporated into the formation of the primordial Appalachian Mountains. 

Washington County provides excellent “windows in time” when it comes to exploring these very ancient sea beds. Also please note that these sites have been compiled from online sources. However, over time, listed sites can unfortunately become inaccessible, while new sites open up to collecting. 

Always remember, “Trust, but verify.” Avoid collecting in state and federal parks, or on posted properties, unless permission has been obtained from the owners.

 The following fossil sites have been gleaned from a list published at www.donaldkenney.x10.mx/STATES/MD.HTM. It is not known if or when the site information is updated.  However, the site listings as given could at least be used as a starting point from which to locate currently productive fossil sites.

The Cambrian Period

The Cambrian Period began about 538 million years ago and lasted until about 485 million years ago.

Fossil sea life of the Cambrian Period in Washington County are somewhat rare, but immense beds of fossil algae (also known as cryptozoons and/or stromatolites) can be found.

Sites where the algae bed have been located include one that is located 1.2 miles south of Antietam Station, and 1.2 miles south of Clear Spring. Both of these sites are located in the Conococheague Formation.

A third site wherein the fossil algae may be found is near Funkstown, 2.8 miles southeast and  1.24 miles south of Pleasant Hill School.

The Ordovician Period

The Ordovician Period began about 485 million years ago and lasted until about 443 million years ago.

Some Ordovician fossil sites suggested by online sources include a site in the Eakles Mills (Keedysville) area, specifically 1.24 miles south of Smithsburg at the mouth of Little Antietam Creek.

The fossils reportedly found there include brachiopods (bivalve shells— meaning they consisted of matching, hinged shells as per scallops and clams—but not related to them).

Another site is located in the area of Funkstown, along the National Highway, in limestone beds, which are from the Beekmantown Formation.  Fossils there include invertebrates (animals without backbones), including mollusks (of which clams and snails are members).

The Silurian Period

The Silurian Period began about 443.8 million years ago and ended about 419.2 million years ago.

Some Silurian fossil sites suggested by online sources include a number of sites in the Hancock area and include fossils from Mifflintown and Rochester formations.

Searching roadcuts to the east and northeast of Hancock is recommended. Both formations yield a vast array of prehistoric species, including sea scorpions, trilobites, brachiopods, and sea lilies (related to starfish and sea urchins). These sites almost certainly contain nautiloids as well, which are the ancestors of today’s Chambered Nautilus.

These formations are typically comprised of thin shales interbedded with limestone layers.

Other Silurian sites have been reported in the area of Roundtop in the Wills Creek and Williamsport formations. 

Species reportedly collectable in the Roundtop area include ostracods (very small, shelled animals), trilobites, brachiopods, and clams.

The Devonian Period

The Devonian Period began some 419 million years ago and lasted until around 358 million years ago and is known throughout the Mid-Atlantic for its rich fauna (animal life). The Devonian Period is well-developed in Washington County.

An exposure of the Early Devonian Period has reportedly been located in the Hancock area in the Oriskany Formation.  The site is described as being located westward 2.36 miles on Creek Road, and south on Sandy Mile Road in sandstone roadcuts.

Fossils found have included brachiopods and sea lilies. Usually, large snails can also be found in the Oriskany.

Outcrops of fossil-rich Middle Devonian Mahantango Formation can reportedly be found in the Keyser (Rawlings) area 6.2 miles south of the of 21st Street Bridge, above the river along the eastern side.

Fossils which can be found there include trilobites, brachiopods, clams and snails, cephalopods (including (nautiloids and ammonites – ammonites are related to nautiloids).  Corals also sometimes occur in the Mahantango, as well as sponges.

Late Devonian Jennings Formation fossil sites can reportedly be found in the Parkhead area, in Sandstone, 6.8 miles east of  Hancock.

Fossils reportedly found in the Jennings Formation include brachiopods and mollusks (clams and snails).

Recommended Equipment

Beginning fossil collectors usually equip themselves with a carpenter’s hammer and a chisel (or screwdriver).

However, the following would be recommended for a successful venture:

    Glasses or goggles (flying fragments of hard rock can travel at an amazingly rapid velocity).

    An actual rock hammer.

    A crack hammer (which is a small, handheld sledgehammer).

    An array of different-sized chisels.

    A knapsack (preferable military-style) or a backpack.

    Fast-setting glue (to make onsite repairs to broken specimens).

    A variety of snap-lock plastic bags for holding specimens.

    Newspaper to wrap specimens in.

    Water, for both consumption, and to use for washing off specimens as needed.

    First-aid kit.

    Compass.

    Topographic and bedrock maps (For the more advanced collector).

Additional Tips

Collectors sometimes like to try to locate fossil sites by using Google Earth before actually trying to visit them, employing such in the hope it might provide insight as to whether or not a potential site still exists, to locate nearby sites, and to determine the parking situation.

When parking at roadcuts, be sure that the car is completely off the roadway, and as much off the shoulder as the site will allow.  Make sure that it is safe to open doors when exiting the vehicle on the traffic-side of the vehicle,

The writer cannot emphasize strongly enough to stay away from state and federal parks and forests, and to be absolutely certain that the land or roadcut is not posted regarding trespassing. 

 Collect only as much as the collector needs (the writer has seen at least two sites completely destroyed by one or two greedy collectors).

Just because an old quarry might be noted as “abandoned,” it is likely that only quarrying has been abandoned, while the abandoned quarry is very likely still on private property!

Additional Research

Already cited was www.donaldkenney.x10.mx/STATES/MD.HTM as a resource for fossil sites in Maryland. Bear in mind that the site list may not have been updated and some sites may no longer be accessible.

Also consider joining a rock, mineral, and fossil club, many of which offer field trips. A list of clubs can be found at www.mgs.md.gov/geology/clubs.html.

Also, the Maryland Geological Survey has published numerous books on the paleontology of Maryland, mostly in the 1960s. Most are free to access online, but again, bear in mind that these are old publications, and sites noted therein, may no longer be accessible, but they may provide direction for further investigation.

Appalachian Mountains; Source: National Park Service

Examples of Silurian Mufflintown Formation Fossils

Top: Coral (Favosites niagarensis) colonies. (Collection of Richard D. L. Fulton)

Middle left: Snail (Hormatoma) shells. (Collection of Richard D. L. Fulton)

Middle Right: Trilobite (Dalmanites limulurus) exoskeleton. (Collection of Bob Cross)

Bottom: Nautiloid shell. (Collection of Bob Cross)