SANTA BARBARA, Calif. (AP) -- Scientists are puzzled by a mysterious Los Padres National Forest hot spot where 400-degree ground ignited a wildfire.
The hot spot was discovered by fire crews putting out a three-acre fire last summer in the forest's Dick Smith Wilderness.
"They saw fissures in the ground where they could feel a lot of heat coming out," Los Padres geologist Allen King said. "It was not characteristic of a normal fire."
Fire investigators went back to the canyon days later and stuck a candy thermometer into the ground. It hit the top of the scale, at 400 degrees.
A dozen scientists, including University of California, Santa Barbara, mineralogist Jim Boles, have been looking for answers since August. Robert Mariner, a U.S. Geological Survey hydrologist who studies volcanic gas vents at Mt. Shasta, Mt. Hood and Mt. Rainier was also called in.
"When I heard about the candy thermometer, I was amazed," Mariner said, noting that the temperature of the volcanic vents he studies is typically 200 degrees, around the boiling point of water. "I thought these guys were pulling my leg."
With the help of an air reconnaissance flight and thermal infrared imaging, scientists found that the hot spot covers about three acres. The hottest spot was 11 feet underground, at 584 degrees.
They found no oil and gas deposits or vents nearby and no significant deposits of coal. The Geiger counter readings were normal for radioactivity, and there was no evidence of explosions or volcanic activity.
One possible explanation still under study is that an earthquake fault may be the source of the heat.
"We can't rule out anything definitely yet," King said.
(Copyright 2005 by The Associated Press. All Rights Reserved.)