Pet for once looked flummoxed. “Well, okay, moving on, then. Have you come up with a name for the quake?”
Hugh smiled at Pet in a fatherly way. “I'm glad we're back on stable ground, not to make a seismic joke. In fact, Pet, it doesn't have to have a name. It wasn't that big an event.” His smile turned wan. “Let's save a name like âthe Salt Lake City earthquake' for the big one. Sorry to downgrade your earthquake, and I don't mean to suggest that it's not newsworthy, but you'll recall that we've had three others in the five to five point five range in the past hundred years around Salt Lake City. Use it for its educational value. Talk about what the big one would be like by contrast.”
The reporter scribbled madly. “Okay, good,” she said. “But really, Dr. Buttons, it's got to have a name. This was a big earthquake for a lot of people. Like the Ottmeier family, whose infant son Tommy was fatally injured when the bookcase fell over on him.” Her sharp eyes focused tightly on Hugh's face, watching for his reaction.
Hugh Buttons closed his eyes, drawing himself inward. “Please don't ask me for a quote on that, Pet.”
Faye interrupted from the far end of the table. “Little Tommy died?” she asked. “IâI didn't hear about that.” Her complexion had paled.
Pet said, “Well, he's not dead yet, but I hear it's imminent. Wow, what a news cycle this one is becoming. All the extra press
personnel who are here already for the Olympics are completely ravenous for the human-interest stories. The parking lot outside the hospital looks like a display yard for media vans with jack-up satellite dishes. ABC, CBS, NBC, CNNâeveryone's down there. And the blood bank's going wild. You know Salt Lakersâwhen there's an emergency, every last one of us rolls out in support.”
“So you're in hog heaven,” Logan said.
Pet gave Logan one deft bat of her eyelashes. “Well, Logan, I suppose I would be if that were the trough at which I fed. But I'm a science journalist, and I'd rather focus on the science. Report the story behind the story, the educational bit that might just help people be a little more intelligent about how they go about living in a huge earthquake fault zone.”
Ted Wimler leaned toward Faye. “The parents put the kid to bed below this humongous oak bookcase that was already leaning into the room, they had so much on it. So much for bookish people being smart, huh?”
Wendy Fortescue whipped her narrow little face his way and said, “Shut up, Ted.”
“How frequent are earthquakes around here anyway?” I asked Logan.
“That depends on the size of quake you're talking about. Felt earthquakes? One like today? About every forty years around here.”
Pet said, “Yes, I'm aware of the earlier quakes that were big enough to get your attention. Let's see: 1910, 1949, and, if you count the one over by Magna, 1962. And Salt Lakers felt Montana's Hebgen Lake seven point five quake in 1959, and the seven point three Borah Peak, Idaho, quake in 1983. I've looked them up on your UUSS Web site. I found the âPersonalizing the Earthquake Threat' section and read the accounts you posted from the old newspapers. Great stuff. And there must have been smaller
quakes, too, right? So it sounds like you begin to have some data. So tell me, what do the data tell you?”
Hugh shifted in his chair and took a sip of beer. “We have anecdotal data, yes, but remember, our records only go back a hundred and twenty-five years. Our seismographs were pretty primitive in 1910, and even though the recording equipment had improved, the instrumentation network was still scanty in 1949, so while we could triangulate the epicenter of those quakes, we couldn't get much resolution on the subsurface picture. Even now, we're struggling to get a more three-dimensional picture. Funding, it's always funding. Seismographs and telemetry cost money.”
“Amen,” said Logan.
Hugh continued. “And again, the local quakes we're talking about are fairly moderate-size onesâthe five to five point five range. Like Logan says, the recurrence intervalâthat calculated averageâfor those is well under a hundred years. But Logan here can also tell you a lot about the big presettlement earthquakesâthe sevensâthat this segment of the Wasatch has seen in the last few thousand years. Always remember, for every whole number larger on the Richter scale, thirty-two times more energy is released. So a seven would release almost one thousand times more energy than a five. Those are the ones that we truly need to worry about. We'd be looking at a lot more than just a few chimneys down, and, ah, so much more than the one casualty.”
One thousand times bigger.
I wondered what, if anything, would have been left of Mrs. Pierce's house after that level of shaking.
Logan bunched his eyebrows again. “I gave you the publications on that, Pet,” he said, “and you should talk to the emergency-preparedness people again to get that from a human angle. Hugh, tell her more about today's event. You said you've begun to paint the slippage. So is it official? Did the movement occur south of 600 North Street? If it's down on a latitude with the survey, that puts it six blocks south of that at least.”
I listened sharply, remembering the map we had looked at together that afternoon. Salt Lake City's street-numbering system is excruciatingly practical, in a weirdly original kind of way, like a lot about its Mormon founders. The street is called 600 Northâthe 600 is not an address, and there is no North Streetâand it's right between 500 North and 700 North. The quirks of the street-numbering system formed the basis for my suspicion that the men who designed Salt Lake City were all engineers, and not one of them a closet poet. But then, Mormonism has always struck me as a religion designed around expediency and practicality, with an answer for every question and a contingency for every eventuality, and no quarter given to spoilers like chaos or entropy or even ambiguity. Which was part and parcel of my disinterest in joining it: as a geologist, I see ambiguities in everything. Or perhaps it's my ability to perceive ambiguities that makes me good at geology.
But I digress. Logan had a gleam in his eye that said he was highly interested in Hugh Buttons's answer. And the degree of his alertness had reminded me of the missing fault line he had added to his USGS map. What had he said? The dashed, or “approximately located,” line had been on an earlier map but had been left off the 1992 edition?
Hugh replied, “Yes, we are confirming that the Warm Springs branch of the Wasatch fault does continue south of 600 North. We're showing movement spanning from 100 North to South Temple.” He shot a quick look at Pet Mercer. “Again, Pet, that's not a very big earthquake. A ground-rupturing quake, a six point five or a seven, would have ripped loose several kilometers north to south.”
“And if we had ground rupture,” I said, still trying to get a handle on the scale of such events, “what would be the vertical throw created by that size quake? How big a scarp would we see?”
Hugh took another sip of his beer. He focused tightly on the
foam at the top. “Again, Logan's your man. What's the rate of vertical movement, Lo? A millimeter per year, right?”
Logan gave Hugh a look that said,
You know damned well what the rate is,
but said, “Yes, that's our best estimate, but that's an average. These things don't go off like clockwork. Earthquake prediction is, as you said ⦠well, not truly possible. There are too few dataâtoo few observationsâand an average is a mathematical construct, not an observation of nature's pattern. And as Em is suggesting, movement on the Wasatch comes in large jumps, sudden releases of stress that are rare by the standard of human experience. Say the recurrence intervalâthat's how often you get an event that size on this segment of this fault, Petâis a thousand years. In fact, the interval is one thousand three hundred and fifty years, plus or minus two hundred. Do the math. That would give you about a four-foot-high scarp running down the middle of West Temple from north of the capitol clear down past the Convention Center. Or worse, because you get back-tilting and antithetic faulting. The place is ripping apart, not just moving up and down. The kind of vertical offsets we see when we are able to cut a trench across the fault are in fact ten feet or more.”
Pet twisted this way and that in her seat, taking notes with great concentration. She hadn't slipped any nuts or raisins out of her pockets in quite a while. “Okay,” she said, “so that would crack a few foundations, right?”
Logan leaned forward onto the table, his green eyes wide with amazement. “You have a quake that size on this fault, it won't matter what's built across it, Pet. Every building within miles not built to Code Four will be badly damaged, if it isn't outright flattened, and we're going to be a whole lot more worried about the dead and dying than about any kind of real estate. We'll have kill rates up to thirty percent. Utilities will collapse, food and clean water will run out, the hospitals and the doctors and nurses that staff them will be under piles of rubble, and we won't be
able to bring in supplies or triage personnel because we'll have bridges down all over the place and the airport runways will be submerged under water draining east from the Great Salt Lake. And even if that water weren't as salty as all hell, it wouldn't be potable, because it will be laced with that tailings pond crud Kennecot's got stacked up behind those levees that are going to breach.”
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It's POSSIBLE THAT Faye's lack of appetite had more to do with Logan's description of a “big one” than with her little hitchhiker's affect on her digestion, but I made up for her gastronomic shortcomings by putting away four pieces myself. The Pie does a good pizza, and I am a glutton when it comes to that all-American combination of Italian ingredients.
Several more geologists joined us before the last crumb and string of melted mozzarella vanished from the table, but I forget their names. They discussed the observations they'd made that day, often stepping around Pet Mercer's questions so they wouldn't be quoted before they were ready, but they did keep the conversation lively by telling war stories about other temblors they'd experienced, where they were during the 1989 Loma Prieta quake, or the latest they'd heard concerning the debate over the geologic setting of the Republic Day quake in India in 2001. Like I said, everybody has an earthquake story, and it wasn't long before they got into volcanic eruptions, landslides, and flood stories.
Out on the sidewalk, as the party began to break up, the subject of recreation suddenly supplanted seismic hazards. A tall blond consulting geologist named Tim or John or something, who had joined the pizzafest late, asked Logan, “So, are we still on for our annual Seismologists on Skis adventure? Or does an actual seismic event supersede swilling beer and skiing?”
“You're right, I got so wound up in that shaker that I forgot.”
He looked around at the others. “When were we going to do that?”
“This Wednesday,” Wendy said. “Day after tomorrow. I think we'd better postpone. I don't want to miss any aftershocks. And ⦠you know ⦔
“Hey,” the tall blond man said, “now that Pet's out of earshot, did you hear that Frank Malone dug a trench down at the new mall site this morning?”
“He didn't!” said Logan, appalled. “What, did he have to get out of his truck for that?”
“Got right down into the trench, I hear. And didn't find a thing.”
“Figures,” said Logan. “He couldn't find his ass with both hands and a roadmap. Didn't phone us, either. Wouldn't want anything so complicated as a second opinion stirring up controversy, now, would he?”
The blond man shook his head in disgust.
I cut in. “Malone,” I said, thinking the name sounded familiar. “Who's he?”
Logan looked out from under his eyebrows. “Oh, just another engineering geologist of easy virtue. Don't mind us. We can't afford to cut trenches very often, but he gets the big bucks from his clientsâyou know, developers.”
“You mean he digs trenches when they're getting ready to put foundations in for big buildings and like that.”
“Yeah.”
“Doesn't the state or the county require that the UGS pass judgment on things like that? I mean, doesn't he have to call you when he's cutting a trench?'
“No, not usually. Not unless the Building Department gets nervous and says he has to get a second opinion, but that doesn't happen very often. We just wish to hell the slimeball would at least give us a squint at his trenches while he has them open.
Hell, we'd do half his work for him, scrape down the sides and all, but he doesn't call.”
“Give up, Logan,” the blond man said. “Malone wouldn't want you looking into one of his trenches. You might see the fault his client doesn't want him to see.” To me, he said, “It's rare as hell to get a look underground at a downtown site. And this one was right on trend with the Warm Springs fault no less, and he cut it just hours after the earthquake. I hear he had it backfilled by lunchtime.”
Hugh Buttons maintained a diplomatic silence. “Well then, it sounds like you ought to go skiing. The fault will keep,” he said. “Fun as this quake was, I keep telling everyone it isn't the big one, so life goes on.”