Workers Clear Quake Debris : Temblor: No injuries, serious damage reported as 5.8-magnitude shaker rouses sleepers from Bishop to Sacramento, tumbles huge boulders onto Yosemite roads.

All roads into Yosemite National Park were expected to be open this morning, free of the giant boulders that were the clearest evidence of the 5.8-magnitude earthquake that roused sleepers from Bishop to Sacramento Tuesday night.

No injuries or serious damage were reported. Nonetheless, it was the strongest California earthquake since the October, 1989, Bay Area quake that killed 63 people.

It struck about 11:15 p.m. in the lightly populated high desert east of Lee Vining, a community of about 400 people on the shore of Mono Lake and the eastern gateway into Yosemite. Residents there said the quake was felt as a sharp yanking motion that slid beds back and forth.

“It didn’t roll it jerked . . . like a dog with a rag,” said Ruby Jo Galloway, 75, at Nicely’s restaurant, the main gathering spot for residents of Lee Vining. Customers Wednesday morning included tourists unable to reach Yosemite because of the road closures.

California 120 into Yosemite over Tioga Pass was closed by a rockslide five miles above Lee Vining. Caltrans said crews would have the boulders cleared by this morning.

Among the stranded were Janelle Sullivan, 26, and Sue Greene, 28, of Sydney, Australia. They had spent Tuesday night at a motel so they could drive into Yosemite in the morning.

“I felt a rumbling and pretty soon Sue was running around saying, ‘What do we do? What’s happening?’ ” said Sullivan. “I told Sue, ‘No, it’s a train, don’t worry.’ ”

On the west side of Yosemite, boulders that toppled out of areas scorched by this summer’s fires briefly closed California 140 near the El Portal entrance. The road was reopened Wednesday afternoon.

More serious damage was inflicted to the Big Oak Flat Road that links Yosemite Valley with Crane Flat. Park spokeswoman Mallory Smith said the steep, canyonside roadway was damaged by heavy boulders and may remain closed two more days.

Other routes into Yosemite remained open and park operations were not affected, although the quake was felt strongly enough in Yosemite Valley for some campers to contact rangers.

Scattered incidental household damage such as broken china was reported in the eastern Sierra, and sleep was disturbed over a wide area of Northern California.

The quake was believed to have involved the Lee Vining fault, one of those responsible for the uplifting that created the Sierra Nevada range, according to seismologist David Hill of the U.S. Geological Survey in Menlo Park.

Hill said the quake was unusual only in that it struck in an area that has been seismically quiet for more than a century. “Since 1850, we have recorded very few earthquakes in that particular area,” Hill said.

A swarm of quakes hit the nearby Bishop and Mammoth Lakes area in the mid-1980s, causing concern about a possible volcanic eruption. But Hill, an expert on the volcanic potential of the Mono Basin area, said there is no reason to believe this quake was triggered by volcanic forces.

“It has all the earmarks of being a purely tectonic earthquake,” said Hill, referring to the movement of giant slabs of the Earth’s crust known as tectonic plates.