Booker wasn’t paying much attention to the discussion. Then Graves casually mentioned how inactive faults could be brought to life by a process called “lubrication.” He likened it to loosening a stuck door hinge with a couple squirts of oil; by reducing friction within the locked fault, you could facilitate motion.
Fascinated, Booker put down his binoculars and listened.
“It’s long been thought mineral fluids or water trapped in a fault could lubricate it enough to trigger an earthquake,” said Graves. “They proved it out in Colorado back in the sixties.” He described how a series of small earthquakes had rocked Denver, an area that had had virtually no seismic activity. During a nine-month period, more than seven hundred small quakes were recorded; then they mysteriously stopped for an entire year. The lull was followed by another outbreak. Eventually, geologists discovered that the Army was injecting contaminated water from weapons production at its Rocky Mountain arsenal deep into the ground.
“They were using bore holes about twelve thousand feet deep,” Graves said. “There was a perfect correlation between the quakes and the injections.”
Miller said, “Remember that USGS experiment in western Colorado? They went out to the oil fields around Rangely and pumped water into some of the wells at high pressure. Guess what? They started getting earthquakes. They could turn them on or off whenever they wanted just by regulating the injections. Turn on the faucet, you get quakes. Turn it off, they stop.”
Graves said, “We had some lively seminar discussions out at Cal Tech about whether you could short-circuit or prevent a big earthquake from happening by setting off a series of smaller quakes. The theory was that if you relieved enough stress building on a fault maybe you could defuse a big one.”
Following the conversation intently, Booker asked, “Could you use a technique like that to relieve the rock stress in this area?”
“Watch it, Ed,” Miller said. “He’s got that wild look in his eyes.”
Booker’s eyes were a dead giveaway whenever he was excited about a concept or an idea. They gave off a burning intensity as they did now. Booker was impatient. He couldn’t wait to rush his two guests back into his spacious living room, so he could ask more questions. He actually nudged them along with light taps on their shoulders.
The room was book-lined and decorated with Navaho blankets and Zuni pottery collected during Booker’s long years at the Nevada Test Site.
“You didn’t answer my question, Ed,” Booker said. He’d begun pacing the length of the room, hands in his pockets, head down. He could hardly stand still. “Could you use the technique you were just talking about to relieve rock stress?”
Graves shook his head. “Even if you were sure it might work—and that’s a huge if in such a geologically unstable area—it would take too long. You’d have to drill all those bore holes and figure out how to get tremendous amounts of water down into the fault at high pressure.”
“You’d also have to decide where to trigger your control quake,” Miller said. “That would be incredibly complicated. And who’s to say you wouldn’t actually set off the very thing you were trying to prevent.”
“But it would still take too long,” Graves insisted. “Granted, we don’t know how much time we’ve got until another big quake hits, if one hits. It might not happen for another two hundred years. But say it was imminent, tomorrow. It would take months, years, and a billion dollars to get enough deep holes bored. The advantage of doing the experiment at Rangely was they were able to use existing deep oil wells.”
Booker had taken out a notebook and was furiously scribbling notes. He stood there a few moments working through a series of figures. Then he slapped the notebook against his leg and said, “Boys, I know a faster way.”
MEMPHIS
JANUARY 14
9:30 A.M.
THE POWER WAS OUT IN THE SPENCER BUILDING. Atkins and Elizabeth used flashlights as they groped their way down a pitch-dark hallway. The ground shook again, another aftershock. The building shuddered and swayed, but the base isolation system cushioned the impact. The walls didn’t buckle or collapse.
“I’m glad to see the aftershocks are finally dying out,” Atkins said sarcastically. Their power and frequency continued to astound him. The ground remained incredibly active.
The building, a modern structure with a handsome, pink granite facade, had escaped serious damage, but the interior was a mess. Desks, computer terminals, and file cabinets were overturned. A bank of security monitors lay shattered on the floor. Office partitions had been knocked over. Window glass littered the carpets.
Atkins opened a door marked with a red exit light and they descended to the basement.
“There it is,” Elizabeth said, playing her flashlight against the far wall. Two steel tables supported an impressive array of seismic instruments, all of them battery powered. There were two types of sensors, both state-of-the-art strong-motion sensing devices: an FBA-23 triaxial sensor and an FBA-11. The data was stored digitally on tape and computer disk. It could easily be downloaded into a laptop.
“Elizabeth, look here,” Atkins said. One of the devices was equipped with a GPS-synchronized clock. The amber “on” light was lit.
“Yes!” he said, clenching his fists. “The GPS network must be back in operation.” If true, it was the best news he’d had in days. They could finally run critical calculations on how much the ground surface had moved during the quake. And, more important, if it was still moving. The amount of deformation would tell them a great deal about whether seismic energy was loading up again in the fault system.
Atkins remembered that the building was also equipped with a GPS monitor. They climbed the stairwell and opened a door to the roof. The GPS antenna, a three-foot-high platform, was bolted to a corner. Its latitude and longitude positions were preset, so it could automatically lock on to the proper array of satellites. Electrical cables connected it to a receiver and modem. A battery and solar panel provided the power.
Like the seismographs, the data was stored on disk. They could format it back at the university. The receiver control panel indicated it had been operational for nearly six hours.
Elizabeth looked out at the city of Memphis as Atkins removed the data recorder. The roof offered an excellent view of the downtown district from the riverfront, extending far to the east. The devastation was much more immediate than when seen from the air. She could feel the heat from the fires, smell the smoke, taste it. Several buildings less than a block away were burning fiercely. One was a high-rise bank. Already big, the fire there was growing larger as a strong wind spread the flames from floor to floor.
Elizabeth tried to count the fires, but gave it up. “No one ever expected this,” she said. The drone of fire engine sirens made it hard to talk without shouting. “We had some fires in Northridge and during the San Prieto quake, but nothing like this. It reminds me of Kobe.”
The fire that had swept through the Japanese seaport in 1995 had almost reached conflagration status. A lot of the construction was wood, small frame houses that went up like dry hay. Memphis was built mainly of brick and masonry, especially in the downtown district. The buildings weren’t supposed to burn, but many of them were doing just that.
Elizabeth was struck by the randomness of the fires. Some blocks were untouched. Others were raging infernos.
“If I’m oriented right, the university’s roughly in that direction,” Atkins said, pointing toward the east with his hands folded. “We’ve got a nice walk ahead of us.”
“How far?” Elizabeth asked.
Atkins shook his head. “Three, maybe four miles.” Getting there wasn’t going to be easy. Not with so many streets blocked. They’d have to pick their way through the damage just as night was starting to fall.
“This wind is really spreading the fire,” Atkins said. It worried him.
Columns of flaming embers sucked skyward were spreading to the roofs of other buildings. To the south, toward Beale Street and the old cotton warehouse district, they were burning more fiercely. Atkins later learned many of the homes in South Memphis were made of wood. It was a poorer, older section of the city, dense with dilapidated, single- and two-story houses. The wind was sweeping burning embers and sparks from those fires
