Tracking Md.'s dinosaurs Paleontology: A 4-inch-wide, three-toed track appears to be the state's first dinosaur footprint in a century.

January 30, 1998|By Frank D. Roylance | Frank D. Roylance,SUN STAFF

EMMITSBURG -- A Washington geologist picking through a rock pile has discovered what appears to be the first dinosaur footprint reported in Maryland in more than a century.

Peter Kranz, a free-lance writer, educator and popularizer of Maryland's dinosaur heritage, spotted the single print this month on a 50-pound slab of red sandstone dug up by housing construction in Emmitsburg in Frederick County.

Just 4 inches wide, the three-toed, duck-like print is barely discernible on the surface of the 210 million-year-old rock. But it appears to be genuine, according to Robert E. Weems of the U.S. Geological Survey.

"It's fairly faint," Weems said. "But it does look, from what I could see of it, like it's probably the footprint of some sort of three-toed beast."

Kranz's guess is that it was made by some sort of small prosauropod -- ancestors of the long-necked, plant-eating giants of later ages. This one would have been 4 or 5 feet long from head to tail.

If so, the find on Jan. 4 represents the first Maryland dinosaur track reported since 1895. (Amateur paleontologists probably have others in private collections, Kranz said. But none has reported the discoveries to scientists or museums.)

In 1895, James A. Mitchell uncovered about 20 small dinosaur footprints on two sandstone slabs found at a rock quarry less than a mile from Kranz's find.

Mitchell was a 43-year-old Johns Hopkins University graduate student and geology professor at Mount St. Mary's College in Emmitsburg. He sketched the three-lobed tracks -- distinctly different from Kranz's print -- and published his discovery. But the rocks have been lost.

Revisiting the site of Mitchell's discovery yesterday, Kranz clambered across the abandoned quarry's weedy, treacherous slope, looking for hints of ancient life. "I always have the feeling that the next rock I turn over will have tracks on it," he said. "The next one has got to be the right one." It wasn't.

Most schoolchildren know that America's most spectacular dinosaur remains have been found in Western states. But few realize that the first dinosaur discoveries in North America were made on the East Coast, beginning in the 1850s.

The first was Hadrosaurus foulki, a "duckbill" dinosaur from the Upper Cretaceous Period dug up in New Jersey. Now New Jersey's official state dinosaur, it is included in the state's tourism promotions.

In 1858, a dinosaur tooth was found in Prince George's County. Named Astrodon johnstoni, it represented the first long-necked sauropod formally described in North America.

Kranz is leading an effort by Maryland schoolchildren to make Astrodon the state dinosaur. They are seeking lawmakers to sponsor their bill. Similar legislation failed narrowly in 1992.

Cretaceous clays in Prince George's County, 95 million to 130 million years old, continue to yield small dinosaur bones and other remains. Others have been found along "Dinosaur Alley," the U.S. 1 corridor from Washington to Baltimore.

Mitchell's tracks, and Kranz's, are twice as old, formed 200 million to 220 million years ago, Weems said. That was the late Triassic Period, early in the Age of Dinosaurs.

Maryland's red Triassic sandstones are found in Carroll, Frederick and Montgomery counties. Similar rocks are scattered from New England to the Carolinas, formed by sediments that washed into "rift valleys" torn open by continental drift.

Weems said seasonal flooding in the valleys created broad lakes and mud flats. Dinosaurs thrived there, but "conditions were not very favorable to preserve bones. What you do see here and there are footprints."

Kranz said the creature that left its footprint on his rock might have been crossing a mud flat in search of water. "Just like in Africa, they've got to go to the water hole," he said.

Kranz, Weems and many others have searched the Gettysburg formation for years. Tracks of larger dinosaurs have been found in Pennsylvania and Virginia. But Mitchell's 1895 discovery remained the only reported Maryland find. It hinted at the presence of smaller creatures. But "at this point, we simply don't even know what these dinosaurs were," Weems said.

Finding more footprints -- or better still, a "trackway," or series of prints -- could reveal a great deal, Weems said. "In a real sense, you're looking at a live animal and its behavior."

Kranz said bones can reveal what an animal was capable of doing. But tracks can show "what they actually were doing. Did the young move separately from the adults? Was there social structure? Was there caregiving?"

"Ichnology" -- the science of reading trackways -- might also reveal how fast the animals moved and in what size groups they traveled.

Kranz said tracks are easier to find than skeletons "once you figure out what they're supposed to look like." He urges Maryland residents to be on the lookout for them where the Gettysburg formation is exposed by construction, road cuts or streams.

"One of these days there'll be some 7-year-old kid out here turning over rocks and finding something," he said. But it's vital first to obtain the landowner's permission before entering private property or removing fossils.

Neither government nor museums can force someone to give up a fossil find. But Kranz encourages amateurs to report their discoveries so that scientists can learn from them.

Kranz organizes school programs and dinosaur field trips. Phone 202-547-3326 or e-mail him at dinosaurfununo.com

Pub Date: 1/30/98

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