TRAVERSE CITY, Mich. (AP) - Explorers have discovered a century-old shipwrecked ore carrier that sank mysteriously during a Lake Superior storm less than two months after it was launched.

All but one of the Cyprus' 23 crew members died in the Oct. 11, 1907, disaster. A team with the Great Lakes Shipwreck Historical Society found the wreckage last month about 460 feet beneath the surface and planned to announce the discovery Monday, said Tom Farnquist, the group's executive director.

The Great Lakes are littered with thousands of shipwrecks. But the Cyprus is among the more puzzling - especially because it foundered on just its second voyage, while hauling iron ore from Superior, Wis., to Buffalo, N.Y.

The 420-foot-long ship is about eight miles north of Deer Park, a village in Michigan's eastern Upper Peninsula, where lone survivor Charles G. Pitz stumbled ashore after floating aboard a life raft for nearly seven hours. He died in 1961, following a long career as a mariner.

Pitz's great-niece, Ann Sanborn, said she hoped the discovery would lead to an explanation of the Cyprus' fate.

"The people who died on that vessel deserve that the truth be brought out, whatever that truth is," said Sanborn, a former sailor. She is now an associate professor in the marine transportation department of the U.S. Merchant Marine Academy in Kings Point, N.Y.

The Cyprus is seen on her maiden voyage, that sank in Lake Superior in 1907.

Built in Lorain, Ohio, the Cyprus was launched Aug. 17, 1907. It was as "seaworthy a vessel as has ever been turned out by a lake ship yard," The Marine Review, a Cleveland trade publication, said after the sinking.

The gale in which the ship perished was "so moderate that only the smaller class of vessels sought shelter while the big steamers scarcely noticed it at all," the Review said.

But Pitz, the second mate, said after the wreck that the Cyprus was being pounded by northwesterly waves and developed a gradually worsening list the fatal afternoon.

The engines finally stopped and crew members donned life jackets. Most headed to lifeboats, but Pitz and three others - the captain, the first mate and a watchman - gathered near a raft closer to the front.

About 7:45 p.m., the Cyprus capsized and quickly sank.

Pitz and his companions were hurled into the lake. They climbed aboard the raft and by 2 a.m. had drifted within 300 feet of land. But the raft flipped over several times in the churning surf, drowning everyone but Pitz, who washed ashore, cold and exhausted.

All but two of the 22 victims' bodies were recovered.

The cause of the wreck is a matter of debate. News reports speculated water had entered the Cyprus' hold through faulty hatch covers, causing the ore cargo to shift and create the dangerous list.

Pitz insisted the hatch covers were battened down, although Sanborn, who has researched the tragedy, said water did get through them.

"There were absolutely no doubts that there were problems with the hatches," she said in a phone interview last week.

Hull damage is another possibility, said Farnquist of the shipwreck society.

Fred Stonehouse, a marine historian and author in Marquette, offered another theory: The Cyprus was doomed by engine or rudder trouble that prevented the crew from staying out of deep troughs between the waves, where ships are especially vulnerable to tipovers.

Farnquist said the shipwreck society would send its underwater cameras back to the site for further study. Two inspections have shown that half the pilot house is missing and wreckage is strewn 270 feet off the bow, he said.

Pitz had estimated the ship was 10 miles farther offshore than it turned out to be - one reason no one discovered the site earlier, Farnquist said.

"It's a relief knowing that finally this ship has been located," said Bill Thorne of Sault Ste. Marie. His uncle, George Thorne, was the watchman who almost made it to shore with Pitz. His body was found three days later, still strapped to the raft.

"Now we have a better understanding of what happened to George," Thorne said.