A mysterious mile-wide dent in the earth has generated a debate among scientists about whether the depression was the catastrophic creation of a meteorite, or the patient work of Mother Nature.
Wakefield Dort Jr., a retired University of Kansas geology professor, will make his case for the crater's unearthly origin at the annual Meteoritical Society meeting in Los Angeles on Tuesday.
Nebraska scientists have their doubts.
"It is not a crater. There is no evidence," said University of Nebraska scientist Mark Kuzila, who has studied the site.
Dort, who has done his own research on the site, hopes his presentation will generate funding for further tests to prove his theory.
"This is an intellectual chasm," he said. "If we had the money, we could settle this in a matter of one summer."
According to Dort's theory, the depression was formed by the impact of a large meteorite that packed an explosion with the force of several hydrogen bombs between 3,000 and 500 years ago.
Dort began studying the site in 1991 after he and some colleagues discovered the unusual dent on a topographic map — a nearly perfectly round formation smack dab in the middle of Nebraska.
Dort's team renamed the depression the Merna Crater after the nearby village of 377 residents.
Because less than 60 impact craters have been confirmed in North America, Dort's initial conclusions caused a media stir, with articles appearing in magazines that included National Geographic, Earth and Discover.
Dort has collected samples from the site and claims he found thousands of minute black magnetic particles not native to Nebraska. He also notes that Pawnee Indian legend tells of a "thundering cloud" that appeared over the area "leaving behind children of black stone."
Dort's team also found a layer of crushed glass about three feet below the surface with a pocket of gray soil underneath.
But University of Nebraska geologist Vern Souders speculates that what Dort found is fulgurite, which is formed when lightning strikes sand.
The Nebraska research included drilling test holes inside and next to the depression, going much deeper than the Kansas team did.
The Nebraskans said they found the crater had the same origin as similar, though less impressive, depressions in the region carved out by relentless winds during dry periods thousands of years ago.
Daniel Britt, a geology professor at the University of Tennessee, said he will listen with interest to Dort's presentation.
"It's another piece of the scientific puzzle," Britt said. "But I don't know if he'll find people with a big sack of money to spend to find out."
In the middle of the debate is 82-year-old Frank Bartak, born in a homestead on the edge of the contentious depression, whose family still farms the land in and around it about 10 miles west of Merna.
"I don't think anybody can prove it one way or the other," Bartak said. "They've been up here poking around for years, and they don't know anymore about it than I do. ...
"If it's absolutely proven to be a crater, there'll be a certain numbers of tourists that will come around, I suppose," he said. "But it wouldn't make any difference to me — I'm not going to run a hamburger stand."