Curious Drawn to New Fissure Left by Quake

What is being called the biggest, deepest known gash in the earth from this week’s quake is in this tiny mountain community, swallowing up the azaleas in Freda and John Tranbarger’s front yard, attracting curious scientists and drawing crowds of gawkers.

The 4-foot-wide, 15-foot-deep, 250-yard-long hole on Summit Road, about 10 miles northeast of Santa Cruz, continued to draw passers-by, picture-takers and tourists to the scenic, redwood forest area on Thursday. Most stood wordless before the trench, awed by the fresh wound in the earth that was a clear sign of the quake’s power.

“You should put up a fence and charge admission,” said one visitor to the Tranbargers, who watched the passing cavalcade of the curious from the front lawn of the relatively undamaged pink clapboard house where they have lived for the last 29 years.

“It’s kind of a landmark, right now,” said Jeff Marshall, a graduate student in earth sciences at UC Santa Cruz. He said the great opening was “the most extensive ground rupture” he had seen in the area.

“This is the biggest thing we saw from the air in three or four hours of flying” over the area near the quake’s epicenter in the Santa Cruz Mountains, agreed Roy Patterson, principal geologist with Dames & Moore, a Los Angeles-based environmental engineering consulting firm.

On Wednesday, excited government and private seismologists and geologists began studying and measuring the opening in the ground that sliced down a long driveway shared by about six homes in the Loma Prieta neighborhood off Summit Road, miraculously missing all of them.

By Thursday, however, experts had determined that although large, the opening was not the signature of geological plate movement along the San Andreas Fault line that they had been looking for.

Had the huge crack actually been caused by the movement of plates, it would have caused a gash 30 miles long, with its width and depth consistent for the entire length, said David P. Schwartz, a spokesman for the U.S. Geological Survey office in Menlo Park. “It’s not long enough and consistent enough,” Schwartz said.

Instead, Schwartz and others said, the opening resulted from soil shifting when the hillside shivered from the quake, which was centered at Lake Elsman, less than two miles away from the hole.

Either way, the massive gap is significant because of its sheer size, several geologists said.

Patterson said the opening is interesting because “it gives you a better understanding of what will happen in the future.”

The Tranbargers’ pink, three-bedroom home, once level with the long driveway in front of it, is now three feet above it. The 1,300-square-foot home did not suffer serious structural damage, but its contents were shaken badly, breaking everything that was fragile, and water service was cut off.

“That’s what’s mysterious to me,” said John Tranbarger, 68, a retired aerospace worker. “As violently as this thing was shaking, our house survived pretty well.”

Experts say a structure miles away from a quake’s epicenter can suffer more damage than a house such as the Tranbargers’ that is close by, in part because the thrust of the quake from its focal point deep underground may deliver itself more powerfully miles away.

Differing soil conditions in various areas also play a role in determining how a quake will affect structures, as do how the structures are built.

The Tranbargers said the force of the earthquake moved furniture, including the family’s piano, and tossed them to the ground several times before the shaking stopped. They climbed out a window after the quake--both doors were wedged shut--and were stunned to see the hole.

Probably in shock, they immediately drew up lawn chairs and sat down to gawk.

“I couldn’t believe it,” said Freda. “It didn’t seem possible. That’s awesome. To look out suddenly and see that you’ve got a two-level” lot.

Freda said most of the geologists who came by to inspect the hole advised the Tranbargers to build steps up to their newly elevated house, to pour a new cement parking area and re-landscape the opening.

Since the quake, the Tranbargers have been sleeping in a shelter at a nearby school. Yet, they are already adjusting to the new look of their front yard. On Wednesday night, they barbecued sausage within 10 feet of the frightening gash.

“We’re just glad to be alive,” said John Tranbarger.