THE UH-60 BLACK HAWK PUT DOWN AT A SMALL National Guard airfield north of Mayfield, where Seismic Commission officials had arranged to have three Ford Explorers waiting out by the runway. The geologists formed two-member teams and fanned out across the southwestern quadrant of Kentucky, the area that had continued to show intense seismic activity.
Within thirty minutes of landing, Atkins and Walt Jacobs were on their way in a rented blue Explorer loaded with three portable seismographs. They had a long day ahead of them.
The teams wanted to set up an array of twelve instruments on a 120-mile line running roughly from the Mississippi River east to Kentucky Lake. The plan was to have the network up and running within fourteen hours, which meant a grueling day. Each team had three or four stops to make, many of them in remote, rugged country.
There was an unspoken sense of urgency. The recent tremor that had struck near Kentucky Lake was the strongest since the magnitude 7.1 event two days earlier. Sixty-eight small quakes had been logged in that area during the last ten hours, most of them a magnitude 2 or less, so weak they couldn’t be felt.
The geologists wanted to harvest as many seismic waves as possible, then use them as earth probes to create computer-enhanced images of what was happening in the ground. It was an unprecedented opportunity to study the crustal rock.
Everyone knew this chance would last only for a short time. They had to gather the data now, before the quakes ceased.
After the discovery of the previously undetected fault that ran south beyond Memphis, Atkins wondered if the strong ground activity in western Kentucky indicated the same thing. Was it possible they’d find another branch or segment of the New Madrid Seismic Zone?
He’d spent much of the day thinking about that and was still mulling over the possibilities as he and Jacobs sped due east on the Sam Purchase toll road. The hazy sky of the early morning had given way to beautiful afternoon sunshine. It was just over forty degrees. Fine weather. Jacobs was driving, pushing well over the sixty-mile-an-hour speed limit. He had a bluegrass CD blaring in the stereo. The sound went perfectly with the rugged countryside.
They were on their way to their last stop—an abandoned coal mine. They wanted to set up one of the portable seismometers underground. This would eliminate the possibility that the instrument would pick up any “background” noise such as automobile traffic. Jacobs had already arranged the trip with the company that owned the mine. The Golden Orient plunged two thousand feet into the ground, one of the deepest mines in the state.
Atkins kept returning to the foreshock-aftershock issue. Were all of these recent miniquakes the gradual winding down of the magnitude 7.1 event? Or were they building to an even bigger earthquake?
He’d been arguing it with himself ever since his meeting the night before with Elizabeth Holleran. He had major doubts about the foreshock theory. He’d already talked it over with Jacobs that morning. It didn’t fit with the historical record, which seemed to mitigate against another big quake any time soon on the New Madrid Fault. The recent pattern there was clear. One moderately big quake seemed to occur every ninety years or so.
But Atkins couldn’t quite forget the glaring exception: the three quakes of 1811-1812, each of them a monster.
Jacobs had calculated that up to fifty percent of the elastic strain energy remained stored in the rocks after the first quake in the famous New Madrid sequence—enough to trigger two more huge quakes. It was a sobering statistic, one that Atkins couldn’t overlook.
As he sat in the Explorer’s passenger seat working over all this, Atkins also realized he wanted to see Elizabeth Holleran again.
It was a surprisingly strong feeling, and it explained why he hadn’t gotten much sleep that night, less than four hours, the first time in a long time anything like that had happened.
Ever since he’d lost Sara, he’d found it hard to relax with another woman, to spend time and make the emotional commitment to get to know someone better. He knew what the problem was; a doctor he’d seen had explained it to him: He was still grieving over Sara’s death. The powerful feeling had lasted for years. This desire to see Elizabeth Holleran was totally unexpected.
Jacobs turned off the toll road and drove north about ten miles. They were near the small town of Kaler about fifteen miles northeast of Mayfield. The mine had been closed for more than twenty years, Jacobs explained. There’d been a fire. Some miners had been killed.
“I don’t know the details,” Jacobs said. “But it must have been pretty bad. They reopened it a couple years later, but then air pollution regs closed them down again. Too much sulfur in the coal. Most of the mines in this part of the country had to shut down for the same reason.”
“How far down do you want to set up the seismometer?” Atkins asked. He wasn’t looking forward to this.
“A couple hundred feet,” Jacobs said. “That ought to filter out all the surface noise. You don’t gain anything by going much deeper.”
A gate blocked the private road to the mine. The facility covered five miles of forested hill country. One of the arms of Kentucky Lake was twenty miles due east.
Jacobs called the mine’s security office with his cell phone. Ten minutes later an elderly guard arrived in an aging pickup. He wore a holstered pistol and red suspenders. His cheeks and chin were covered with white stubble.
“I been expectin’ you all morning,” he said curtly, getting out of the truck to unlock the gate. “Follow me.”
“Friendly guy,” Atkins said softly.
“They warned me about him,” Jacobs said. “He’s been here forty years. Lost his job when the mine shut down. Stayed on as a guard.”
They drove up a gravel road that dead-ended at a parking lot. The mine entrance was inside a corrugated metal building with massive doors. A ten-story derrick that operated the elevator cables towered over it.
With each of them gripping the seismograph’s metal carrying case, Jacobs and Atkins followed the guard through a side door. The old man flipped a breaker switch. Overhead lights flashed on. Atkins heard heavy machinery groan to life somewhere above them, high up on the derrick tower.
The elevator was a metal cage large enough to accommodate fifty men.
The guard handed each of them a scuffed miner’s helmet.
“The levels are marked on the wall in red numbers,” he said. “Just push the buttons to go up or down.”
“Are you going with us?” Atkins asked.
“No, sir,” the guard said. He hesitated. His tone softened. “I don’t think you boys ought to be going down there.”
“Why not?” Atkins asked. The man was staring at them, wide-eyed, not blinking.
“Something ain’t right.” He looked like he wanted to say more but changed his mind. “You get in any trouble, hit the big yellow button on the elevator control panel. It’ll sound an alarm.”
“What happens then?” Jacobs asked.
“I’ll call for help,” the guard said. “You’ll have to wait ‘til it gets here. That could take a while.”
He slammed shut the elevator’s metal grill. Jacobs pressed the red button for Level 2. The cage started down with a rust-grinding lurch. There were twenty levels, descending two thousand feet. A single light bulb burned over their heads.
“I wonder what he wanted to tell us,” Atkins said.
“I’m kinda glad I didn’t find out,” Jacobs said. “Mines spook me enough as it is. I never could have worked in one.”
As they slowly descended, it occurred to Atkins that this was the deepest he’d ever gone into the earth. A geologist for more than twenty years, he’d spent his entire life on the surface. The profession hadn’t taken advantage of these man-made deep spots in the earth.
Reaching Level 2, they carried the seismograph about twenty feet into the coal tunnel. They could see only as far as the lights on their helmets penetrated the darkness. It was cool, almost cold, the only sound being the steady dripping of water from the rocks.
They got the battery-driven seismograph up and running in about ten minutes. Jacobs plugged a small laptop computer into the unit. It was an analogue machine. The seismic activity appeared digitally on the computer screen.
“Jesus Christ, John! Look at this,” Jacobs said, playing a flashlight on the screen. “This ground’s alive.”
The readouts startled Atkins. He’d never seen such intense seismic activity. All of it was way under magnitude 2. The waves were too weak to be felt, but they were coming in ten- to twenty-second intervals.
“I can’t wait to get a directional reading on this,” Jacobs said. They’d need to let the seismometer run awhile to harvest enough data to get a precise fix on the source of the waves and their direction.
Atkins felt something brush his cheek. He looked up and saw coal dust falling from the ceiling of the shaft.
“Do you smell that?” Jacobs asked.
Atkins straightened up. He smelled the faint, unmistakable odor of rotten eggs. Hydrogen sulfide. The foul gas that made the air around Hawaii’s Kilauea volcano so tough to breathe. Atkins had been to the volcano several times. He’d recognize that distinctive odor anywhere.
Hydrogen sulfide was usually associated with volcanoes. Pockets of the gas formed deep underground and were released like champagne bubbles during eruptions. There’d been reports of strange odors seeping from the ground. He remembered how the farmer, Ben Harvey, had complained that his well water smelled bad.
“We must be getting some venting,” Jacobs said, referring to a natural vent or crack that allowed the odors to escape from the ground. But that didn’t explain what was causing the smell.
“Hold on, listen!” Atkins said.
A faint rumbling came from the depths of the mine. It was hard to pinpoint the exact source, like trying to locate a sound underwater. It seemed to be coming from all directions at once, the sound rising up from the deep earth—distant, strange, unreal.
Atkins had never heard anything like it. He had an overpowering urge to get out of there fast. He felt trapped.
A loud groan reverberated in the tunnels, the sound echoing back off the walls, building like thunder. Then, as abruptly as it had begun, the rumbling stopped. It was as if someone had thrown a switch. The silence was total.
Atkins felt his heart pounding in his chest. He was pouring sweat. It stung his eyes. He’d kept waiting for a tremor, tensing for it.
“Maybe we ought to go a little deeper,” Jacobs said.
Atkins looked at his friend for a moment. Neither spoke.
“All right,” Atkins said. “Let’s do it.”
They picked up the seismometer and computer and got back into the elevator cage. Jacobs pushed the button for Level 10, halfway to the bottom of the shaft. The big car started to descend. They were going down another eight hundred feet.
The farther they descended, the stronger the smell became. By the time they reached Level 8, both of them had pressed handkerchiefs over their noses and mouths. The odor was almost overpowering.
Jacobs waved his hands to indicate they’d gone far enough. He was coughing.
The elevator cage was open on the sides. Atkins touched the rock wall. The rough stone was almost hot. Then he noticed that his feet were getting warm. The cage’s steel floor was heating up. Warm air was blasting up from the bottom of the mineshaft.