Fossil or concretion? Huge rock baffles experts

NEWPORT — What some thought might be a 20 million-year-old fossil tortoise in the rocks on a beach in Lincoln County has scientists baffled.

After visiting the site Tuesday, Oregon state paleontologist William N. Orr, Bill Hanshumaker of the Hatfield Marine Science Center and Guy DiTorrice, an amateur paleontologist who bills himself as "Oregon Fossil Guy," couldn't decide whether they were looking at a turtle or a tortoise, or whether it was a fossil or a concretion.

One thing is for certain: the removal of the discovery reported last month by Lincoln City spa owner Carol Ritzert could be dangerous to anyone involved. The rock is believed to weight about 1,500 pounds.

To determine whether the 2-by-3-foot domed rock was a fossil, the three scientists looked for sutures, which are lines where the bones knitted together.

"If these are sutures, they would have to be fractured because there are way too many," Hanshumaker said.

"I'm sure it's got something inside of it, but I'm not sure it is a turtle," Orr offered.

"I've never seen a concretion that size," DiTorrice said. "It's geographically significant, animal and-or mineral. It needs to be sitting in a museum."

Getting it to a museum could be quite a feat.

Concretion is organic matter that decomposed differently from surrounding material, making the dirt harder. DiTorrice said, "This type of fossil is not normal for this rock formation, so it has significance just by its size and shape."

Ritzert said erosion revealed the formation over a year's time. It sits about five feet off the beach, beneath a deteriorating overhang at an undisclosed location.

All three scientists agreed that the rock would probably be freed during the next storm season, but Orr said that waiting for erosion was risky.

"If the thing rolls out and anyone is around, there is a good chance of it rolling over someone," he said. "If it rolls out, the whole cliff could go. Even if it's an egg, it's not worth a life."

Then there's the question of handling.

"Cracking it open could damage or destroy what's inside," DiTorrice said. "Sometimes it's better just to leave a specimen whole and use it for reference."

"We call this an interpretive opportunity to show people something we found on the trail," he said. "It causes people to think about geology, paleontology and just to think about what caused this."

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