Laurel area rich in dinosaur fossils is dedicated as a park

By Jonathan Mummolo
Washington Post Staff Writer
Tuesday, October 27, 2009

More than 65 million years ago, before the continents reached their current configuration -- and ages before industrial parks and shopping centers existed -- a warm and swampy swath of what is now Prince George's County was home to dinosaurs.

The creatures' remains in the area have endured weather, erosion, tectonic shifts and modern industry. But their chances of being discovered improved Monday, when 41 acres south of Laurel were dedicated as Dinosaur Park.

"It's the most important dinosaur site east of the Mississippi River," said geologist Peter Kranz, president of the Dinosaur Fund, a Washington-based nonprofit organization that supports dinosaur fossil research and preservation in the region.

"Each time it rains, something new comes out," Kranz said.

The park, which the Maryland-National Capital Park and Planning Commission oversees, is just beyond a dead-end street at an office park. Although to the untrained eye it could be mistaken for a pile of muddy rocks, the spot has been a veritable fossil factory for more than a century.

In the 1850s, slaves mining iron pits in the area began unearthing bones. In 1858, geologist Philip Tyson, Maryland's state agricultural chemist, was surveying the area and found teeth in the clay. He took them to a Maryland Academy of Sciences meeting, where they were confirmed as dinosaur teeth -- specifically, those of a massive herbivore eventually named Astrodon johnstoni, now Maryland's official state dinosaur.

The find touched off more than 150 years of sporadic but prolific fossil discoveries in the area, helping scientists render an increasingly detailed portrait of the lush, diverse environment of Maryland in the Cretaceous period.

Ensconced in a warm climate similar to southern Louisiana's were long-necked, plant-eating sauropods such as Astrodon, 60 feet long and weighing several tons; predators akin to velociraptors; freshwater sharks, turtles and crocodilian reptiles; and some of the first flowering plants the world ever saw.

Most of the bones found in the park -- teeth, toes, vertebrae -- represent a small piece of a skeleton, making it difficult to pin them to a specific species, experts said. Still, the range and volume of fossils there makes it one of the most productive sites in the eastern half of the United States, said Matthew Carrano, curator of dinosauria at the National Museum of Natural History.

The site has been particularly useful for studying the animals' early stages of life, as it has yielded a number of baby dinosaur bones, he said.

"People have been going back to this site for 150 years," Carrano said. "In more recent years, it's tended to be owned by companies, and, happily, many of them have been very willing to allow scientific exploration. . . . Not only is it important to preserve the site because it contains the potential for ongoing scientific discovery, but also because it's really not appreciated locally that there are dinosaur fossils" in the region.

The highlight of the park is a fenced-off area of about an acre littered with rocks, the remnants of ancient trees known as lignite and, to the discerning eye, dinosaur bones. That area is part of 7 1/2 acres donated by the surrounding office park's developer, Jackson-Shaw, which also supplied the parking area, gardens and fence. An additional 34 acres were dedicated to the county as part of the approval process for an area development in the 1990s.

The park recognizes the site's human past, as well. The entrance is flanked by large chunks of ironstone, or siderite, and features crushed brick paving, a reference to the brickyard that operated there for much of the 20th century. Large signs tell of the African American slaves and freedmen who worked in the mines, as well as fossil discoveries that stretch from Tyson's to that of a father and children, who in 1991 found a massive Astrodon thigh bone.

Members of the public will be able to hunt for the fossilized time capsules alongside experts who will be working at the site and donating fossils to the Smithsonian Institution. The park will offer programs on the first and third Saturday afternoons of each month, and group tours will be available by appointment.

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