Look Down for Dinosaur Fossils In and Around Laurel

Astrodon johnstoni. Discovered in 1858 at Dinosaur Park in Laurel, MD. Source: Natural History Society of Maryland.

Did you know that Greater Laurel is a hotbed of dinosaur and early mammal species? Just look down. Fossils may be under your feet in your own yard.

Dinosaur Park in Laurel. Just a short distance from downtown Laurel and the Patuxent Research Refuge is Dinosaur Park off Contee Road near U.S. Route 1. The Department of Parks and Recreation, Prince George’s County, Maryland-National Capital Park and Planning Commission (M-NCPPC) owns and operates Dinosaur Park. This site preserves an Early Cretaceous deposit, dating to ~115 million years ago, and is one of the best dinosaur fossil sites on the U.S. East Coast. The Cretaceous Period lasted from ~145 million years ago to 66 million years ago, spanning about 79 million years. It was the final and longest period of the Mesozoic Era and concluded abruptly with the famous asteroid impact that wiped out all non-avian dinosaurs.

Dinosaur Park preserves a rare “bonebed” with animal and plant remains, including:

• Astrodon (Maryland’s state dinosaur — a large plant-eating sauropod)

• Priconodon (armored nodosaur dinosaur)

• Acrocanthosaurus (apex predatory theropod)

• Deinonychus (a feathered raptor)

• Ornithomimoids (the ostrich-mimic dinosaurs)

• Other animal fossils (crocodiles, turtles, fish, snails, and clams)

·         Plant remains (ancient Sequoia relatives, cypress, cycads, and early flowering plants)

In the 16th and 17th centuries, Richard Snowden and other early colonists began mining the iron ore (siderite) in the Muirkirk region. Iron furnaces located throughout the region melted down the ore to produce iron and steel used in construction and manufacturing. In 1858, African American miners working in open pit mines were the first to discover dinosaur fossils in Maryland. These fossils were passed on to Phillip T. Tyson, the Maryland State Agricultural Chemist, while visiting the iron mines to produce a geologic map of Maryland.

In 1887, paleontologist Othniel Charles Marsh sent John Bell Hatcher to Maryland to search for more dinosaur remains from the Muirkirk deposits. Hatcher recovered hundreds of fossils, which were eventually transferred to the Smithsonian Institution after Marsh passed away. Arthur Bibbins, a geology professor at Goucher College, was also a prominent collector in the Muirkirk region, although he primarily focused on fossil plants.

In December 1995, the M-NCPPC acquired 22 acres encompassing several sites that expose the Muirkirk deposits. The park protects these sites from development and unrestricted collecting, while also providing an outdoor laboratory for community science. The public is invited to work alongside professional and amateur paleontologists to help uncover and preserve new fossil discoveries.

The late Dr. Peter Kranz was one of the leading proponents of the site and led efforts to name the Astrodon johnstoni as the Maryland state dinosaur in 1998.

Dinosaur Fossils at NASA Goddard Space Flight Center.  Along with Dinosaur Park off Contee Road, amateur paleontologist, Ray Stanford, identified dinosaur tracks in 2012 near a parking lot at NASA Goddard Space Flight Center (GSFC). Dating to over 100 million years ago, the site consists of a large 8’ x 3’ sandstone slab with dinosaur and mammal tracks, potentially containing 70 distinct tracks from eight species, including:

• Nodosaurs (heavily armored, four-legged herbivorous dinosaur)

• Sauropods (long-necked plant-eaters)

• Theropods (bipedal carnivores) 

• Pterosaurs (flying reptiles)

• A variety of small mammals

“The concentration of mammal tracks is orders of magnitude higher than any other site in the world,” said Martin Lockley, paleontologist with the University of Colorado, Denver. “This is the mother lode of Cretaceous mammal tracks” potentially containing 26 distinct mammal footprints. Some of the small tracks are so unusual that scientists named a new ichnospecies (Sederipes goddardensis) based on them.

Why This Is Important. These footprints capture a snapshot in time when animals walked across muddy ground that later hardened and preserved their prints. Because they record behavior (movement) rather than just bones, these fossils are especially valuable to understand how dinosaurs and early mammals interacted in their environments. The find was formally published in Scientific Reports (January 31, 2018).

Keep Looking Down. So, next time you are walking around a stream bed in Laurel or Patuxent Research Refuge, keep looking down for unusual stone features. You may uncover the next major dinosaur that roamed what we now call Laurel. However, please keep in mind that it is illegal to collect fossils on M-NCPPC property without a permit. If you do come across a fossil on park property, report the find to the M-NCPPC Paleontology Unit at dinosaurpark@pgparks.com.