FAIRPORT (AP) - A wooden beam that has long been the focus of the search for a 17th century shipwreck in northern Lake Michigan was not attached to a buried vessel as searchers had suspected, but still may have come from the elusive Griffin or some other ship, archaeologists said Wednesday.
Shipwreck hunter Steve Libert discovered a 10.5-foot section of the timber jutting from the lake bed 12 years ago in an area where he was convinced that the Griffin, commanded by the French explorer Rene Robert Cavelier de la Salle, sank in 1679. French experts who inspected the beam in recent days said it appeared to be a bowsprit - a spur or pole that extends from a vessel's stem - that was hundreds of years old.
Crews have been digging since last week beside the timber, where sonar readings indicated that one or more objects that together exceeded 40 feet long were submerged in mud. Libert and other expedition leaders believed they might be the hull of the Griffin, and that the excavation would find a connection between it and the presumed bowsprit.
In this photo taken June 16, divers inspect a hole being dug beside a wooden beam jutting from the floor of Lake Michigan that an exploration group believes may have been part of the 17th century ship the Griffin.
But on Tuesday, as a diver was widening the pit, the timber began wobbling. Archaeologists and leaders of Libert's Great Lakes Exploration Group decided to take it down instead of trying to stabilize it, fearing it was a safety risk. So the diver eased it to the lake bed after checking beneath and discovering that it wasn't attached to another object, but simply had been embedded in the tightly packed sediments.
Even though no other wreckage was found, project manager Ken Vrana said there's still a chance the ship is nearby. With the timber no longer in place, crews stepped up their dredging operation in hopes of reaching a hard surface that a probing device indicated is 18 to 20 feet down. But they reported late Wednesday that they had found only bedrock, with no signs of a vessel.
"It could be that the ship is very close to this area, but it is impossible to say for sure at this point," said Michel L'Hour, director of France's Department of Underwater Archaeological Research and a shipwreck expert.
Members of the expedition team pointed to other hopeful signs: The bottom of the timber was cut at an angle suggesting it might have been fashioned to fit into another structure; and the timber's full length proved to be just over 19 feet, similar to that of bowsprits on other French vessels from La Salle's era. The upper end is tapered, and a series of fastening pegs are attached to the side.
Leaders were discussing whether to leave the timber in the lake for the present - wrapped in protective cloth and hidden to shield it from theft, vandalism or accidental damage from contact with objects such as boat anchors - or bring it ashore for safekeeping. Recovering it would allow further study and perhaps eventual display, but would require expensive treatment to prevent deterioration.
Michigan's state archaeologist, Dean Anderson, who has received daily phone briefings from the searchers, told The Associated Press he favored keeping the beam submerged while long-term options are considered.
"Any time you bring a water-logged item off the lake bottom, it would be a complicated and difficult process," Anderson told the AP in a phone interview. "In this case, I don't think we know what this piece is. We would need a lot more information about it before anyone would consider bringing it up. Leaving it down there is a good solution."
Anderson's office has the ultimate say because the state asserts jurisdiction over Michigan's Great Lakes bottomlands - including shipwrecks, although officials have acknowledged that if the Griffin is found, it will belong to France.
He said he wasn't unhappy that the beam was dislodged, even though a research proposal submitted by Great Lakes Exploration Group agreed to keep it stable.
"These sorts of plans are based on the best information you have at the time," Anderson said. Removing it from the sediment didn't appear to do any damage, he added.
Libert and the state battled for years in federal court over control of the suspected Griffin site before reaching a settlement in 2010. The Department of Natural Resources, which includes the state archaeologist's office, issued an excavation permit that expires Friday.
Copyright 2013 The Associated Press.