Beach Elementary Parking (38.68313062 -76.53615)
Brownies Beach, officially known as Bay Front Park in Calvert County is a fossil hunter’s paradise! Brownie's Beach is one of the few publicly accessible beaches on the Chesapeake Bay. Fees apply during the summer. Pack a bag and plan to spend the day along the beach fossil hunting. However, there are no provisions available at Bay Front Park so bring your own water and refreshments. Parking during the summer months can be challenging with the high number of beach goers. There is no fee to use Bay Front Park during the winter. However, they do charge during the summer. During the summer, you can park for free at Beach Elementary School and walk directly across the road to reach the boardwalk that leads to Brownies Beach.
The Calvert cliffs begin in Chesapeake Beach and extend south to the Drum Point area of the County. Three geologic formations of Miocene age (approximately 6 to 20 million years old) are exposed in the Calvert cliffs. The layers of sediment are inclined slightly to the south, so that progressively younger beds are exposed from north to south along the cliffs. The oldest is the Calvert Formation and is on the northern end in Chesapeake Beach, progressing to the younger Choptank and St. Mary’s Formations to the south. The cliffs contain some of the largest deposits of marine fossils from the Miocene Epoch found on North America’s east coast. The cliffs are continually eroded by the waves, freeing the fossils. Prehistoric shark’s teeth and whale vertebrae wash up onto the shores of Calvert County, and are highly prized. Complete skeletons of whales and porpoises have been found, along with bird bones and the partial remains of mastodons, peccary (a wild pig-like mammal native to North America), and small horses from the Miocene epoch. Examples can be seen at the Calvert Marine Museum in Solomons, Maryland (http://www.calvertmarinemuseum.com/paleontology.htm).
The geological history of Brownie's Beach
Brownie's Beach lies at the northern most tip of the famous Calvert Cliffs. As you walk along the beach or if you wade out in the bay, and look back at the cliffs from a distance, you can clearly see several distinct layers. The deposits at Brownies Beach are part of the Calvert Formation which was formed in the early-middle age of the Miocene period. The total thickness of the Calvert formation is about 60 meters, but part of that is already below ground/water level at Brownies Beach.
The Miocene was a period of uplift in Middle America and the Antillean region, that was accompanied by folding of the crust of the earth and volcanism. Erosion of the recently uplifted areas produced extensive deposits of clay, sand and marl. Some of these sediments were consolidated, forming shales and sandstone. During this time, North and South America were united, and the island of Florida joined the Georgia mainland. The North American continent assumed approximately its present outlines.
The Chesapeake Group is divided into three formations. The oldest, the Calvert Formation, is composed of diatomaceous earth and dark sandy clays and marl. It is overlain by the yellowish sand and greenish clay and marl of the Choptank formation. The youngest deposits belong to the St. Marys Formation, which, as exposed at Little Cove Point, consists of bluish sandy clay and fine sandstone. The silty and sandy content of the Miocene deposits in Maryland was derived from the erosion of older Coastal Plain deposits and crystalline rocks of the Piedmont region. The calcareous deposits are organic in origin.
Within each formation, you can identify distinct layers, from fine blue clays, to coarse red sands. These are called Members. Different members were deposited under different circumstances, from shallow seas to tidal flats, and contain different types of fossils.
The shores of Brownies Beach are abundant will fossilized shark teeth and bones from dolphin, rays, shark and whale. You can easily find a variety of shark’s teeth by sifting through the sand on the beach.
Digging and climbing on the cliffs is strictly prohibited!!
Most commonly found are the teeth of the lemon/grey shark, tiger shark, contortus, and sand tiger, but you can also find hammerhead, bull, cow, snaggletooth, mako – and even the occasional megalodon! Fossil hunters have even located megalodon teeth ranging from 2-5 inches in size at Brownies Beach. Most of the teeth you will find are 0.25-0.5 inches long. The more common larger teeth are around 1 inch long. In addition to all this you can find manta ray dental plates, various bone fragments from sharks, dolphins, and whale.
You can find additional information on the Maryland Geological website at http://www.mgs.md.gov/esic/fs/fs10.html and for facts on Miocene sharks teeth: http://www.mgs.md.gov/esic/brochures/sharks.html.
To log this Earth Cache:
1. Email the answer to the following question: Please describe the cliffs and the different coloration of the layers.
Optional: Post a picture of yourself at Brownies Beach with your gps and
As an added bonus, not a requirement, post a pic of your fossil finds. You can try to identify your finds using the following sources:
http://www.mgs.md.gov/esic/brochures/teeth/index.html
http://www.fossilguy.com/sites/calvert/index.htm
Parking: N 38° 40.694 W 076° 32.122