Years of scraping away stones and sifting through loose dirt taught Dave Hacker some valuable lessons on fossil finding. So when the recent storms dumped nearly 10 inches of rain on the area, the Silver Spring resident grabbed his trowel and headed to the Dinosaur Park in Laurel to see what he could find.
What he found was the largest dinosaur fossil to come out of the park in five years — likely a bone from an enormous plant-eating dinosaur and proof that after 300 years of digging, the metropolitan region’s soil has plenty of buried history left to discover.
“Typically what we have here are small fragments and bones, but in this case it’s a much larger bone,” said Mr. Hacker, who has made a hobby out of volunteering at the Dinosaur Park. “It caught my eye because it looked a little different. To the untrained eye, it looks like a big rock.”
The fossil was freed Wednesday from its 100-million-year grave by Smithsonian Institution preparator Steve Jabo. The size of a head of cabbage and the color a dirty potato, the fossil was wrapped in plaster for safekeeping until a team of lab technicians and volunteers at the Smithsonian’s National Museum of Natural History could clean and identify the bone.
Last week, scientists from the Johns Hopkins University announced that a fossil found in College Park belonged to a hatchling armored dinosaur called a nodosaur. It was found in 1997 in a creek bed and was donated to the Smithsonian.
As Mr. Jabo delicately shoveled a mixture of wet soil, clay and wood away from the large fossil, he told curious onlookers the type of bone Mr. Hacker unearthed will be quickly identified, but narrowing it down to a type of dinosaur could take time.
However, a good guess is that it came from an Astrodon, an enormous herbivore with a long neck that also happens to be the official dinosaur of Maryland.
Scientists estimate an adult Astrodon could stretch 60 feet nose to tail and weigh several tons. About 20 years ago, a 6-foot, 220-pound femur from one of the large reptiles was discovered in the park.
“It’s a significant find for the park,” said Donald Creveling, archaeology program manager for the Prince George’s County Department of Parks and Recreation. “What makes this park significant is that it’s one of the only places east of the Mississippi River where dinosaur bones and fossils are regularly found.”
Fossils are found on the surface of the park, but the heavy rains are what allow erosion to occur and reveal new specimens.
While Wednesday’s excavation was limited to professional diggers, throughout the year the park opens to the public so that average history buffs can lend a hand in the fossil finding.
Archaeologists from the Smithsonian haven’t made the trip to Laurel in five years, said Peter Kranz, a paleontologist and the educational program coordinator for the Dinosaur Park.
The park sits at the far end of an industrial park, about three miles northwest of the Baltimore-Washington Parkway, and just off Route 1.
Though the site is halfway between Washington and Baltimore, the history of the area lends itself to a rich supply of fossils.
More than 100 million years ago, Maryland’s climate and geography was similar to the bayous of today’s southern Louisiana.
When a prehistoric stream that ran near the park would flood, the flotsam such as dead animals and tree branches would be lumped together into a sort of log jam.
“Virtually every kind of dinosaur is represented” in the park’s fossils, Mr. Kranz said.
As the millennia passed, sediment layers shifted, compressed and buried the wide-ranging organic material.
As Mr. Jabo continued to unearth the fossil, there was a palpable feeling of anticipation as the hole got deeper. About two hours after the dig began, the roughly 4-pound fossil was pulled from the ground. It wasn’t all that observers expected, but it was impressive enough for Mr. Hacker to remark that the idea of “bigger is better” tends to be the default opinion for fossils.
“Really, it’s a complete skeleton that is better,” he said.