Beneath more than 120 feet of Lake Huron water, archaeologists have found one of the most elaborate prehistoric stone structures ever discovered in the Great Lakes region.

The main portion of the 9,000-year-old structure has been dubbed Drop 45 Drive Lane; it features a walled stone lane which leads into a cobblestone cul-de-sac-like structure. Nearby are hunting blinds, where Paleo-Indian hunters would have hid as caribou were corralled down the lane and into their trap.

"It is noteworthy that V-shaped hunting blinds located upslope from Drop 45 are oriented to intercept animals moving to the southeast in the autumn," explained John O'Shea, an archaeologist at the University of Michigan and lead author of the new study detailing the remarkable underwater discovery.

"This concentration of differing types of hunting structures associated with alternative seasons of migration is consistent with caribou herd movement simulation data," O'Shea said, "indicating that the area was a convergence point along different migration routes, where the landform tended to compress the animals in both the spring and autumn."

The discovery offers insight into the advanced nature of hunting techniques of prehistoric people in the Great Lakes region. It also offers archaeologists a more accurate picture of the size and organization of Paleo-Indian groups, as well as how they cooperated on extensive hunts.

"The larger size and multiple parts of the complex drive lanes would have necessitated a larger cooperating group of individuals involved in the hunt," he said. "The smaller V-shaped hunting blinds could be operated by very small family groups relying on the natural shape of the landform to channel caribou towards them."

The Paleo-Indians that might have used such hunting structures were the descendants of the Homo sapiens who first inhabited North America after migrating across the Bering Strait from Asia -- some 47,000 to 14,000 years ago.

O'Shea's research and study -- which was published this week in the Proceedings of the National Academy of Sciences -- was assisted by Michigan colleagues Ashley Lemke and Elizabeth Sonnenburg, as well as Robert Reynolds of Wayne State University and Brian Abbot of Nautilus Marine Group International.