A moderate earthquake shook southwestern Utah early Wednesday, triggering a rockslide that closed Zion National Park and sent three houses slowly sliding down a hillside.
Minor damage was reported elsewhere. No injuries were reported.
Dozens of people called radio stations with reports of cracks in windows, foundations and ceilings in older homes, as well as buckled sidewalks and asphalt.
Walter Arabasz, director of the University of Utah Seismograph Stations, said the earthquake measured 5.9, while the U.S. Geological Survey estimated the reading at 5.5.
The quake occurred at 4:26 a.m. and was centered five miles southeast of St. George, a town of 28,000 just a few miles north of the Arizona state line, Arabasz said.
Boulders, some more than 20 feet in diameter, blocked the highway leading from Springdale into the south entrance of Zion, 50 miles northeast of St. George.
Springdale Mayor Bob Ralston said state road crews did not know if their equipment could handle the rocks, some the size of small automobiles.
Sheriff’s deputies evacuated the three houses in the Balanced Rock subdivision. Ralston said the three homes had slipped at least 30 feet and would have to be demolished.
The north end of town was without power and officials said it might be days before it can be restored.
“The power poles broke off like toothpicks up there,” Ralston said. “The power lines were just hanging, and they had to cut them.”
In Springdale, a town of 275 near the park’s south entrance, Louise Excell and her husband were awakened “with a horrendous boom, almost an explosive sound,” she said.
The shaking lasted eight to 10 seconds, she said.
“From both sides of the canyon, we could hear the rocks falling,” she said. “And that was the scariest part, because it was pitch dark.”
In Zion, people staying at the park lodge were asked to leave because of the lack of electricity, said park spokesman Denny Davies. The park’s two entrances were closed to incoming traffic.