FAIRPORT, Mich. (AP) -- After nearly a week of searching the muddy Lake Michigan bottom, a research team has failed to find the wreckage of a 17th century ship — but leaders said Thursday they weren't giving up.
The mission to locate the Griffin, which was commanded by the French explorer Rene Robert Cavelier de la Salle and disappeared in 1679, was buoyed earlier this week as French underwater archaeologists inspected a wooden beam protruding 10.5 feet from the lake bed. They said it appeared to be a bowsprit — a spur or pole that extends from a vessel's stem — that was hundreds of years old.
But there was no ship below, only hard-packed claylike sediment extending to bedrock 20 feet down. The scientists and divers searched a wider area Thursday near Poverty Island, a few miles offshore of a remote section of Michigan's Upper Peninsula, with equipment that probes beneath the lake bed for signs of buried objects.
Again, no Griffin. With their permit from the state Department of Natural Resources to excavate the lake bottom about to expire and rough weather forecast, they didn't plan to return to the site Friday but said they might next week.
Ken Vrana, the project manager and one of four U.S. archaeologists participating in the expedition, said he expected the group would have no trouble getting a new or extended permit.
Team leader Steve Libert admitted there was growing frustration, but the retired intelligence analyst who has sought the Griffin for nearly three decades remains convinced the ship is there and said he had no intention of abandoning his quest. He discovered the timber — which was loosened from the pit this week — while diving in 2001.
"What other ship out here in the Great Lakes is 300 years old? There's only one that it could be," Libert said. "I'm extremely disappointed that we haven't found it yet ... but it's just a matter of time."
Vrana said the goal wasn't just to find the Griffin, but to determine whether the location was a shipwreck site.
"We have definitely found the component of a shipwreck," Vrana said. "It was not attached to any underlying hull, but that doesn't mean that 100 feet or even several hundred feet away there isn't a shipwreck. So, the search continues."
The team based its search location on both the timber and sub-bottom sound wave scans by an independent contractor that suggested a field of objects covering an area about the estimated size of the Griffin — more than 40 feet long, 18 feet wide — might lie just beneath the lake bed.
Turns out, the sonar readings apparently had picked up a thick layer of invasive quagga mussel shells and distinct layers of sediment, Vrana said.
"This is one time that science is just not working right," said Libert, who spent about $80,000 on the surveys and says he has pumped more than $1 million into the quest. "There's something wrong, either with the machinery or the interpretation or the way it was used."
Michigan's state archaeologist, Dean Anderson, told The Associated Press in a telephone interview Wednesday he believed the expedition was worthwhile — regardless whether the Griffin is found.
"This is the sort of investigation that really needed to happen ... to get an answer one way or another," Anderson said. "I would say it is leaning toward the indication that a vessel is not there. I just don't see any evidence that makes it look like there's a wreck."
The group submitted a proposal to Anderson on Thursday to remove the wooden beam and take it ashore for further study and eventual public display. It calls for wrapping the nearly 20-foot-long timber in protective cloth and taking it to a secure facility for treatment to prevent deterioration after possibly being submerged for centuries, Vrana said.
Anderson told the AP on Wednesday that recovering it would be "complicated and difficult." But Libert said leaving it could invite vandalism or theft.
"After everything we've been through, to take this piece and rebury it and have even the slightest chance of someone finding it — I just don't want to take that risk," he said.
Vrana said the state archaeologist's office had agreed to take the proposal seriously and provide an answer next week.
The state claims jurisdiction over Michigan's Great Lakes bottomlands, including shipwrecks, although officials have acknowledged that if the Griffin is found, it will belong to France.
Libert, who battled the state in court for years seeking to be designated custodian of the Griffin, disputes its ownership of shipwrecks.
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