On Shaky Ground

by Nance, John J. ;

  The crunch of gravel and rocks beneath the tires of the pickup rose above the gentle sounds of crickets, wafting on a soft breeze in the relative cool of early evening. The headlights of the truck cut through a slight veil of dust as the vehicle crawled up to the saddle between two rolling hills, turning left then, following the dirt road as it flanked the V-shaped draw which marked the main trace of the San Andreas Fault, then climbed to the top of the westernmost rise and onto the crest of Car Hill, which was capped by a small wooden structure known locally as the laser house.

  The tall, youthful-looking driver bounced out of the cab, unlocking the building and flipping on lights in a practiced, fluid series of movements. Amidst the hum of microwave transmission equipment and the chattering of computer disks loading their programs, he began opening the wooden shutters on each of the building’s four sides—shutters which normally covered the path of a Star Wars—style two-color laser (called a theodolite) which sat on a pedestal in the middle of the small, instrument-packed room. With the laser, the relative motion of the Pacific plate and the North American plate as they grind past each other in the deceptively beautiful setting of Parkfield could be tracked to within a millimeter.

  Some three nights a week, after teaching the schoolchildren of Parkfield and joining his family for dinner, Duane Hamann repeated that ritual trek, spending several hours putting on a semiprivate laser show over the pastoral countryside, and gathering data which just might help predict the next quake. That was the aim of the Parkfield project: to attempt to identify enough preliminary changes along the fault to justify a short-term earthquake warning (of days or even hours), and to gather as much knowledge as possible about what happens to the fault before an earthquake.

  Duane Hamann had helped build the laser house, and had signed on with great enthusiasm as the plans of the USGS scientists and the Colorado team garnered enough funding to build the structure. Hamann, it was decided, would do the nightly work of pointing the gun at a network of eighteen reflectors mounted carefully on distant hilltops in all directions, measuring with great care and repeated practice the exact distance between the center of the laser house enclosure and each distant point—measurements precise enough to detect movement of half a millimeter.

  “We think of the ground as solid and stable,” he explained, “yet I sit up here and take these measurements night after night and see the different points move for weeks slowly in one direction, then reverse course and move the other way for awhile—movements only a fraction of a millimeter in length, which are better described as trends. Anyway, sometimes it’s instrument error—which is why I take so many repeated readings—but most of the time it’s because the surface out there is more fluid than we think. It almost undulates.”2

  With boundless enthusiasm Hamann spends his hours on the hill carefully adjusting the laser, entering data in the computer, swatting at a squadron of determined summer insects attracted by the incandescent lights, then bounding outside to adjust something. Returning inside, he begins aiming the laser with meticulous precision at a dark point marked only by a reference line on the interior of the laser house shutters. Gently massaging the small knobs which turn the laser housing, barely moving them as if adjusting an unsteady telescope, he works at it until a sudden, pulsating flare of red and blue light erupts from a previously dark spot on a distant hill—light easily visible from within, yet as much as five miles distant.3

  Within seconds the oscilloscope behind Hamann begins to show a three-peak wave form indicating a good reading, and the digital counter begins measuring the time it takes the pulses of laser light to make the round trip at approximately 186,000 miles per second. Smiling at the steady data, he makes notes on an emerging printout before turning back to the laser to find the next reflector.

  Night after night, always looking for changes reading after reading, Hamann has maintained one of the basic monitoring networks across the fault.

  And from the valley—across the Van Horn Ranch toward Turkey Flat, to the east, or northward toward Parkfield itself—the occasional sight of the low-powered laser light describing thin lines overhead on misty nights has been as familiar a part of life since 1984 as the sight of green government vehicles and antenna-festooned plastic igloos (housing more seismic monitoring equipment) has become an accepted part of the Parkfield landscape.4

  To anyone who visits Hamann and the laser house and gets to know the equal enthusiasm of Bill Bakun, Alan Lindh, Bob Burford, and the rest of the cadre of USGS scientists who have focused their professional attention and their reputations on Parkfield, it is obvious that there is an element of chance in the Parkfield project.

  “The worry all of us have,” a senior seismologist in the university community pointed out, “is that the USGS is putting all of their eggs in one basket on prediction. Parkfield is very necessary, and the project must be done, but that’s not enough. What happens if the quake doesn’t come in by 1993? Will the scientific community and Congress lose interest in prediction? What happens if the precursory indications don’t happen anywhere else, or can’t be scaled up to larger earthquakes? Do we give up? I’m afraid a failure could damage the whole prediction program.”

  The lesson, though, is that Parkfield is only one element of a vital program of government and academic research looking for the methods of bringing short-term and intermediate-term earthquake predictions to the point that they can be expressed in terms of probable date, time, place, and magnitude.5

  Long-range prediction is already here, and intermediate-range predictions are approaching the viable stage with seismic gap theories and numerous other observations of changes that occur in the area of an expected earthquake in the weeks and months before the event. While some seismologists such as Dr. Bruce Bolt of Berkeley feel that precise, worldwide short-term predictions will probably not be possible for many decades, if ever, the search for more information must not fall victim to cost cutting and the loss of federal funding. Such projects as the deep drilling probe of Dr. Mark Zoback of Stanford on the southern San Andreas near Cajon Pass east of Los Angeles, and the continuing research of Dr. Kerry Sieh, along with many other programs, are too important to surrender to the Gramm-Rudman-Hollings budget-cutting act or any other federal cutback.6 And there is a very profound reason: On the way to the ultimate goal of short-term prediction, a project of scientific research will usually discover many new things not directly anticipated. And some of those discoveries may be extremely important. The ability to detect not only what faults underlie the city of Los Angeles, for instance, but to have some idea when they’ll move and what magnitude of seismic waves they’ll produce, could have prevented deaths and the imperilment of thousands in 1971.

  And, it would turn out, the same would be true in the fall of 1987.

  Chapter 25

  Whittier, California—Thursday, October 1, 1987

  On Tuesday, the county building inspector had closed his notebook and looked at the young priest for a moment before speaking, his inspection of the sixty-four-year-old Catholic school complete for another year.

  “Y’know,” he began, “if your school building was in Los Angeles, I’d have to condemn it.” He let the words sink in before continuing.

  “But, since you’re here in Whittier, and you don’t have a stringent seismic building code in this town, you can keep on using it.” The inspector shook his head slightly and rose from the table, extending his hand.

  It had been a passing curiosity to Father Tony Ross. Only sixty-two days had gone by since his posting at this new assignment. While he was quite aware of earthquake potential in the Los Angeles region, the full meaning of the inspector’s words had not penetrated.

  Until now.

  The sudden shudder, the rattling of the windows in the rectory chapel had caught him in mid-sentence while officiating with the other clergy and staff members of St. Mary’s Church at morning prayer, two days after the inspector’s visit. The school day was scheduled to begin in less t
han twenty minutes in the old masonry two-story building fifty feet to the west of the chapel, across a small alley through which garbage trucks sometimes rumbled in the mornings about this time. Tony Ross figured that was the explanation: A heavy truck passing by.

  But the altar had begun to move within a second, bouncing and vibrating as the entire building came alive, shaking with an east-west motion, the overhead lights now bouncing wildly, as he prepared to speed up his conclusion of the devotional service and shifted instead to a half-shouted, half-bellowed command to the others in the chapel:

  “Everybody out!”

  As their feet began propelling the group toward the one side door, Tony watched in shocked fascination as the eleven-hundred-pound marble altar rose up off the floor in what appeared to be a slow-motion, vertical levitation, then pitched forward six feet, rotating as it went, wine and hosts and chalice scattering in all directions, throwing itself away from where he and his fellow priests were standing, crashing to the floor of the chapel as they maneuvered to escape.

  Plunging into the smoggy morning air hanging over the courtyard and noting the wildly swinging power lines that were threatening to fall on his new, tiny compact car, Father Ross ran headlong into a new sound, clearly audible above the thunderous rumble and growl of what was obviously a serious earthquake.

  Voices were coming from the direction of the school, across the alley. Voices of children. Voices screaming in terror.

  Oh, my God! he thought. They’ve been hurt. The memory of the building inspector’s words, coupled with the image of several hundred students assembled in the passageways around and between the walls of the old school flashed through his mind as he lunged through the gate and into the alley. If the side wall of the unreinforced masonry building collapsed, it would descend on anyone below—and parents usually dropped the kids off in that exact spot on such mornings. As he rounded the corner of the school, a huge crack in the east wall opened and closed again as the vibrating of the quake continued—then, suddenly, stopped.

  The alley was full of students; but the walls had not fallen, and the children were being led away to the safety of an open area to the south by the assistant principal as Father Ross reached them.1

  As the priests, nuns, and staff of St. Mary’s School swung into action, fearful of immediate aftershocks, their 1923 school building of brittle masonry—a building barely held together by ancient mortar—stood fatally wounded. Within twenty-four hours it would be condemned, even under Whittier’s relaxed codes.

  Somewhere beneath the Montebello section of Los Angeles, about nine miles south of Pasadena and about six miles east of the downtown district, a previously insignificant snag had for many years held back the slippage of one of the many complex fractures which underlie the Los Angeles basin. The fault had reached its breaking point at 7:42 A.M. by lurching slightly, readjusting pressures placed on it at odd angles from other subsidiary faults over untold years, all driven indirectly through the pushing and jostling of many tectonic blocks and “flakes” by the inexorable movement of the great tectonic plates past each other thirty miles to the north along the San Andreas Fault.

  Montebello, however, is five miles northwest of Whittier. Somewhere beneath the surface, the alignment of the fractures included a break which dipped from the town of Whittier to the northwest, intersecting the portion of the fault which snapped. Instead of throwing the brunt of its seismic convulsion up and out in a unified spherical fashion, the energy released at 7:42 A.M. channeled itself inordinately to the southeast, angling upward and toward Whittier, ripping into the town in a northwest to southeast swath, shaking brick chimneys apart, escalating nine hundred houses into major repairs or eventual abandonment, knocking down seventy-year-old plaster walls and younger stucco facades, shattering unreinforced brick walls and cinder-block foundation supports, destroying a new city clock, collapsing a parking garage, and raining down bricks and ornamental debris with fury as its shaking threw personal possessions, fixtures and furniture, pictures and pots to the floor in a thousand area residences.

  Gary Strait had been sleeping when the lurch threw him to the floor in his rented house just to the west of the downtown section. There had been no warning, just a sudden “whooom!,” and instantly all the objects in the upstairs shelves and cabinets were throwing themselves out into the room as if propelled by some poltergeist from a Steven Spielberg movie. Strait tried to struggle to his feet, fighting the rain of objects, stumbling over debris on the floor as he almost threw himself onto the gyrating stairway, stumbling down to the first floor in time to see the plaster raining off the walls and the bricks of the fireplace exploding outward, daylight visible beyond. By the time he reached the front door, stunned by the crashing sounds from behind, the 1912 home had come apart internally. Beneath—as with so many other ill-supported residences in the area—the house had jumped the foundation blocks.

  As Gary fled through the door and the fireplace collapsed, a delicate, crystal bud vase which had sat daintily on the now-shattered mantel, flew, unseen, through the air, catapulting off its perch. As the seismic waves subsided and the creaking, groaning house became still once again—shafts of morning light cutting ineffectively through the heavy pall of dust like spotlights through a smoky auditorium—a small object was barely visible in the middle of the ruined Oriental carpet now covered with broken bricks and plaster. The crystal bud vase—flowers still intact—sat upright in a tiny clear space, as if placed there in requiem for the fragile, ruined home.

  Twenty-three-year-old Lupe Exposito and her twenty-two-year-old sister, Rosa, had been walking toward their 8:00 A.M. classes at L.A.’s California State University when the seismic waves from beneath Montebello began gyrating the campus. Their car behind them in the underground parking garage, they continued up the pathway, bordered on one side by a retaining wall made up of individual slabs—a design which had escaped the requirements of good seismic engineering. As with the inherently dangerous tile and concrete facades on the J. C. Penney Building in Anchorage (which descended like battering rams during the 1964 Alaska quake), the first few seismic waves from Montebello shook one of the slabs loose almost instantly, gravity taking over at the acceleration rate of thirty-two feet per second/per second, causing the multi-ton mass of unyielding artificial rock to gain enough speed to impact the pathway beneath in a thunderous roar, shattering one corner as it struck, then flopping over.

  Rosa Exposito had seen the blur of motion and felt the impact. It startled her mightily, but it was microseconds before she realized that Lupe no longer walked beside her. Turning in terror—her path of vision followed by one other student to the rear who had watched helplessly as the slab descended—Rosa could see only the slab of concrete flat on the sidewalk.

  But where was Lupe?

  The student fifty feet behind had already seen too much. As Rosa Exposito looked around in confusion and growing horror, her heart leapt to her throat as she fought with her mind’s offered explanation of where her sister might be. George Torres already knew. He had closed his eyes in horror as the slab fell, but now he had spotted Lupe’s blue book bag at the edge of the concrete monolith, and a portion of Lupe’s arm protruding from beneath it, already encircled in a crimson stain. The ground was still shaking, but it was not noticeable in the enormity of what had just happened.

  “My sister! My sister is under there!” Rosa began screaming, suddenly aware and determined to get help, determined to find some way to lift the weight from Lupe, lift her back to her feet, deny that this horror had ever happened. She had to be all right. Despite appearances, she had to be okay!

  Rosa, a popular medical technology student at California State, struggled to get someone to listen, to help, to pull her sister out while there was still time.

  Which, of course, there wasn’t. It was too late, as those who tried to comfort Rosa and lead her away knew instinctively.

  Lupe Exposito had been three years old when the slab of inadequately anchored con
crete that would cut her life short had been raised into position along the pathway. It, and tens of thousands of structures like it (especially those which predated the 1971 San Fernando quake), stood like seismic time bombs throughout the metropolitan area, always primed to be torn loose in even moderate earthquakes—bricks and blocks and walls and concrete structures which man can build, but whose impact no human can survive.2

  Just above Altadena in the San Gabriel Mountains north of Pasadena the first jolt from the quake had caused a cave-in in a six-foot-wide excavation being prepared by a construction crew for a new electrical transmission tower. Several men at the intermediate level of the thirty-three-foot deep shaft scrambled out, but for forty-one-year-old Antonio Bernal, the dislodged tons of dirt and rocks which caved in on his position at the very bottom pinned and suffocated him within minutes.

  Juan Herrera had lived through a killer quake in his home country of Guatemala in 1976, a quake which killed twenty thousand people and left his family homeless and destitute. Looking for better income to send home, he had worked in Los Angeles for ten years, finally becoming a legal alien one week earlier, living in a tiny second-story apartment over the meat market which employed him in Maywood, a part of east Los Angeles. The seismic waves that lashed out from the focus of the quake beneath Montebello traveled fewer than five miles before reaching the building at 7:42 A.M., where Juan was taking a shower. With the memory of collapsing adobe buildings in 1976 vivid and fresh in his mind, Herrera reacted instantly, throwing open the bathroom window and propelling himself through it in an instant, perhaps helped by the lurching of the quake. Wet and naked, he landed at the foot of the still-intact building, seconds before the shaking stopped. Exactly what had gone wrong with his attempt to break the two-story descent was not clear to his friends at first, but Juan Herrera had miscalculated his chances with American buildings, and had paid an ultimate price. Having landed on his head, he lay severely injured and bleeding in front of the shop. Herrera would be dead by late afternoon, the third fatality in what would be called the Whittier quake.3