Still Shaken : Aftershocks Are Terrifying Reminder in Yucca Valley

Paul and Cathryn Roll have a more intimate acquaintance with the newly discovered Eureka Peak Fault than most residents near this much-shaken High Desert city: It runs right across the narrow yard between their house and swimming pool.

On a hill adjacent to the Rolls’ property, the fault that scientists first traced after the April 22 Joshua Tree earthquake--and became visible to all on the morning of the June 28 Landers quake--is now marked by a six-inch scarp, a vertical disruption. In their yard, on flat terrain, it has shoved aside a walkway by about the same measure.

“A geologist told us that if the house had been over the fault, it would have split it from one end to the other,” Cathryn Roll said as she gave visitors a tour. As it was, the fault missed the dwelling by 10 feet; neither it nor the pool was damaged.

More disturbing are the numerous aftershocks that continue to rattle the upland area between two and six miles southeast of Yucca Valley.

There have been hundreds of temblors, although they have tapered off in recent weeks.

“If they happen at night, you just sort of lay there and wait for the next one,” said ranger Joni De Bus at the nearby Joshua Tree National Monument. “It’s kind of nerve-racking.”

Scientists who have named and mapped the Eureka Peak Fault have identified it as a secondary rupture zone of the magnitude 7.5 Landers quake and its precursor, the 6.1 Joshua Tree quake.

Along this secondary fault in recent weeks there has been what a U.S. Geological Survey scientist said was “considerable after-slip,” or a slow widening of the rupture. The fault extends for about 10 miles into the national monument.

Strangely, more of the aftershocks from the Landers quake have occurred along the Eureka Peak Fault rather than along the main Landers rupture zone, which spans 45 miles over three previously known faults north of Yucca Valley.

This has caused concern among some earthquake scientists that there could be another large aftershock, perhaps magnitude 6 or stronger, southeast of Yucca Valley, where they fear ground stress may remain high.

Meanwhile, the aftershocks that have occurred have compounded the psychological trauma affecting some resident.

Bill Fry, a social worker sent to Yucca Valley by San Bernardino County authorities under a federal disaster grant to counsel quake-rattled residents, said he is focusing primarily on helping about 60 schoolchildren with the most serious problems.

Fry has found that some children were alone in their homes when the Landers quake hit at 4:58 a.m., their families away on early morning fishing trips or other excursions.

These children are often the most afraid.

“Some are still sleeping in their parents’ beds,” Fry said.

One recent night, the counselor met at a church in nearby Pioneertown with a concerned father who said his 9-year-old son had finally been weaned from his parents’ bed weeks after the fateful morning. He was sleeping on a mattress in the hallway between rooms when a 4.7 aftershock hit at 1 a.m.

Now, the boy has come back to his parents’ bed, and the weaning process must begin anew, the father told Fry.

The counselor said the sizable aftershock interfered with one of his favorite tactics, which is to advise parents to tell their children: “If there’s no aftershock that wakes you up for three weeks, then we’ll begin sleeping apart.”

Three nights a week, Fry holds informal group counseling sessions with anyone who wants to attend, and he has widely distributed leaflets entitled “Emotional Recovery After a Disaster,” which explain that “acknowledging feelings and stress is the first step in feeling better.”

One piece of the leaflet’s advice that schools have sought to implement is to prepare for a quake by putting together a disaster emergency kit. Children have been encouraged to bring blankets, two large cans of fruit or vegetables and 2 1/2-gallon containers of water.

Larry Kirschmann, an attendance officer for the Morongo Unified School District, said teachers have sought to reassure their pupils that classrooms are built to withstand quakes and are among the safest places to be if a big temblor strikes.

For children who remain upset, Kirschmann said, the district seeks written consent from parents to refer them to Fry. He said the district has about 10,000 students, and 60 have had to undergo protracted counseling.

“Most of our students have come around,” he said. “Actually, we have a few teachers, new to the area this year, who are as disturbed as the kids.”

Another problem in the aftermath of the quake has been rumors.

When an odor of hydrogen sulfide was noticed in the Yucca Valley area in August, said town manager Sue Tsuda, some residents suggested it meant a volcano was about to erupt.

It turned out the stench--noticeable for several days in an area from the Imperial Valley as far west as Moreno Valley near Riverside--came from decay of organic matter at the Salton Sea during a severe heat wave.

“We’ve had all kinds of rumors, from 10-foot sand worms coming out of the ground to the quakes being caused by metal balls in a hollow Earth,” said Tsuda. “Fortunately, the aftershocks seem to be diminishing in frequency and intensity.”