Thousands of years of human activity along the Upper Peninsula's Lake Superior shoreline have come into sharper focus after three years of research.

Scientists from Northern Michigan University's geography department recently completed a project at Pictured Rocks National Lakeshore that located 23 new archaeological sites.

The researchers also helped define the shoreline as it existed 4,500 years ago.

Department head John Anderton said the National Park Service-backed effort was designed to find cultural resources so they can be protected during future road building and other developments.

"In the first year of the project, satellite imagery was used to identify distinct land forms, notches, ridges and barriers created by wave action, to map the older shorelines," Northern Michigan spokeswoman Kristi Evans wrote on the school's Web site. "They found that the water was 30-40 feet higher than it is today."

Anderton said today, the federally protected land isn't very habitable.

"But if you go back a while, there were nice places for people to live," he said. "There were embayments, or shallow water lagoons, that had a variety of fish and plants — everything a hunter-gatherer would need."

In the second year of the project, colleague Robert Legg carried out modeling of archaeological sites, using known sites to help find new ones with similar features.

Detailed digital elevation models made by professor Robert Regis let Anderton and students pick likely places to dig.

According to Anderton, past researchers "might do a hundred tests and find nothing. But one out of four of ours unearthed artifacts. That's called smart archaeology."