A Crack in the Edge of the World (15 page)

And so the Geological Survey of Oklahoma promptly put one of the mine shafts, abandoned for three-quarters of a century, to good use again. Technicians placed an array of seismometers deep inside the mine, then ran a coaxial cable up to a seismograph, and placed this in the only convenient, safe, and constantly monitored location they
could find at the time, which was the Meers general store. It sits there still today, close by the main entrance, glanced at only occasionally by the cowboys coming in for their Meers Burgers and shakes and bottles of beer. The instrument's recording drum turns slowly behind a protective plastic cover, its dials flicker, and its celebrity status is underscored by a vanity wall of yellowed press clippings that tell of its importance to the seismic world, and of the sensitivity of this particular machine. Earthquakes that happened on Diego Garcia, more than 10,000 miles away, were recorded on the drum at Meers, it says on the wall; but also, lest any visiting artilleryman try to show off, the guns firing out on the butts twenty miles away at Fort Sill never seem to cause the machine to record the slightest sympathetic tremor.

So far the seismograph has recorded only one earthquake of any size that was definitely caused by movement on the Meers Fault—and since monitoring what everyone agreed was an alarmingly large and unpredictable fault was the purpose of the machine, some might regard this as a problem. This one movement was very small and took place in April 1997: since then, total seismic silence. Which makes seismologists all the more curious: Just when, the geological community wants to know, is the fault going to rupture?

It is a classic of its kind. It is primed, tense, filled with stress, and ready to pop at any moment. But it seems to want to do so only every millennium or two—alarming for those who live around Meers (though in truth no one seems to mind one whit; and the owners of the store appreciate the curious travelers who drop by to inspect the machine), and alarming, too, because there are perhaps many thousands of faults just like those at Meers waiting to break and cause who knows how much mayhem, at unpredictable times of their own choosing.

Knowing a little about Meers makes one far less confident, far more skeptical, about the newfangled science of earthquake prediction. The notion that we might one day be able to forecast quakes is a quest that ultimately motivates all seismic research—or the funding for it, at least—even if few seismologists care to admit it. And the sheer capriciousness of deeply hidden fault systems like those in Oklahoma serves mainly to remind researchers that it will be a long, long time before a predictive technique can be devised that will offer an anxious general public any useful degree of certitude. For although earthquakes do tend to happen in seismically obvious places—like San Francisco and Sumatra—they do also take place in the less predictable places, just out of seismic orneriness.

The general store in Meers, Oklahoma, features enormous hamburgers in addition to a seismograph, which sits, ticking away imperturbably, beside one of the refrigerators.

HERE IN THE MIDDLE
of the North American Plate, far from the unstable edges where all the action takes place, are four locations where earthquakes simply should not happen but do: the Ramapo Fault in New York; the Summerville-Charleston axis in South Carolina; the New Madrid and Wabash Valley nexus in Missouri and its
neighbor states; and the Meers Fault in Oklahoma. All of these are classified as intraplate events—they occur within the stable-sounding centers of tectonic plates. There are similar examples from around the world: Ungava in western Canada, Christmas Day 1989; Newcastle, Australia, in 1989, three days later; Killari, India, 1993.

And in America, too, there have been yet others. Some, such as the huge quakes of central New Hampshire and Cape Ann, Massachusetts, are only dimly recorded and only in the geological record, since they happened long before there were Americans on hand to write accounts. More recently, there are records from sudden single events that puzzle and perplex to this day: the Grand Banks Earthquake of 1929 (which broke submarine cables and spawned waves that killed dozens in the outports of Newfoundland); and three still-notorious New York State events: Massena in 1944, Goodnow in 1983, Ardsley in 1985. They are sporadic, intermittent,
unpredictable
—and as a consequence they are much more dangerous to those living innocently near them than are the more generally expected earthquakes of California, where the cities make sure that buildings are made superstrong and the public is kept endlessly aware.

The specific causes of these intraplate earthquakes are various. The proximate cause of events at Meers, for example, is explained away as the existence of, and occasional movement along, one very particular fault. The subterranean machine that causes the New Madrid quakes is driven by the reaction that occurs when two very different kinds of faults intersect and collide with each other, right under the town.

The ultimate cause of events like these is more interesting, however—as well as being disarmingly simple.

The best theory that anyone has these days for the underlying cause of all intraplate earthquakes is that they represent the relief of stresses built up eons ago, when the mountains or valleys or areas of basin and range were themselves being created. It is eminently reasonable to suppose that the plates themselves, being buckled and elevated and twisted and compressed at their edges, were subject to stress far away from where the buckling and elevation most dramatically occurred.

A piecrust, as it is heated in the oven, will bow upward in the middle, where the fruit bulges and expands in the heat; it will also buckle up at the edges, where the heat conducted through the pan becomes most intense. In the area between the bow and the buckle, the crust, the second it emerges from the oven, lacks the nearly smooth and unblemished appearance it had when first placed inside: It now has myriad cracks and crevices, bulges and breaks. All of this may add to the pie's charm, but it also suggests something of the stresses that built up in the crust as it was being cooked. Once the pie leaves the oven, and the temperature and pressure begin to ease, the cracks change and the aspect of the surface alters: The cracks start to widen or narrow, the surface perhaps tries to revert to its original unblemished and undistorted self, and the stresses that mounted during the cooking process are generally relieved—until a kind of stasis is achieved and the pie becomes what it will be, until it is eaten.

And that, more or less, is what has happened and is still happening in the stable-sounding central parts of all tectonic plates. Almost all of the events just mentioned—Meers, Cape Ann, the Grand Banks, Ardsley—seem to have resulted from the relief of the kind of stress patterns that are illustrated by the cooling piecrust.

But New Madrid, as it happens, is rather different. Some researchers now believe that the origins of the Mississippi Valley seis-micity in this place have a rather more dramatic cause. They believe that here the North American Plate may be trying to split itself into two new plates along the line of major seismicity. Explorations of the deep underneath of the region suggest that material might be welling up out of the mantle well below the earthquakes' epicenters. And, while this does not detract from the analogy of the pie—piecrusts can split into two if suitably stressed—it does have awesome implications for the region. Missouri would then become in a geological sense rather like Iceland, but covered with soybeans, cotton, and corn: It would turn into a place peppered with slow-moving volcanoes and hot springs and cliffs that move apart from one another. And there would in time be two Americas, drifting apart at the rate that fingernails
grow, and with an as yet unnamed ocean in between, and somewhere drowned deep below, New Madrid, in what was once called Missouri.

No one can tell how much stress has built up in the millions of years since the Appalachians and the Rockies and all the other plate-edge mountains were created; nor can anyone say how long it will be before the middle of the continent achieves the kind of stasis that rules out all future earthquakes, forever. The only way one can make any attempt at rationally planning for earthquakes in places like this, where, generally speaking, earthquakes do not happen, is to look very closely at those places where they have, albeit very infrequently, taken place. By doing this, one has a faint hope of imagining what could take place at some infuriatingly unspecifiable time in the future: It is only by looking at what has occurred in years gone by that one can imagine what might yet occur.

The most venerable of the guiding mantras of geology is that
the present is the key to the past
. But in the very different world of seismicity it seems more prudent to suggest the converse, that
the past is the key to the present
. And, of course, to the future.

FROM HERE
it was on westward, to Amarillo and the wide-open skies of the far western prairies. I drove, for hour after hour, through a perfectly dry landscape of buttes and mesas, of arroyos and tumbleweed, of lonely gas stations and wind pumps that clacked emptily in the hot breeze.

And then, just before sunset, there rose ahead the silhouette of a range of enormous hills, and behind them a jagged line of range upon range of mountains, their summits capped with snow. This, at last, was the range once called the Stone Mountains, now much more familiarly known as the Rockies. This was not yet the end of the North American Plate—but it was the beginning of the end, the part of the North American continent that came most directly under the influence of the forces that converged and coalesced at the end, out at the edge. This was now, in the strictest sense, the American West. It was a place
where the geology was all so very different from what had gone before—a place where the mechanisms that caused the mightiest of all America's earthquakes started to become tangible, and visible.

The car began to labor up the first of the fronting slopes. The sky was filled with stars, and the night air suddenly began to feel brisk, and then very cold.

          
Give me men to match my mountains.

Inscription in the state capitol, Sacramento, said

variously to be the message sent back east by the first

arriving Mormons, or an old Australian settler poem

          
California, more than any other part of the Union,
          
is a country by itself, and San Francisco a capital.

J
AMES
B
RYCE
,

The American Commonwealth,
1901

A
T THE TIME OF THE SAN FRANCISCO EARTHQUAKE
, America was a country well on in maturity, having freed itself from the grip of the British crown some 130 years earlier. But California was still young, and many who lived in San Francisco in 1906 would have been alive and alert when the territory was granted statehood and first welcomed into the nation. California had at the time been American territory for just fifty-eight years, formally a state for fifty-six years, and had enjoyed the benefits of a formal constitution for not much more than a quarter of a century.

America's newness as a nation is very much more evident in the West than in those eastern states where the country had its beginnings. And America's ownership of this western half is the consequence of the five separate occasions since independence when the government in Washington conducted negotiations and signed treaties that vastly increased the country's size.

There was the astonishing Louisiana Purchase in 1803, for instance, when Thomas Jefferson persuaded France to sell its 530 million acres between the Mississippi and the Rockies, which overnight doubled the size of the country. Then, in 1846, after a series of bellicose threats, London was finally persuaded to hand over the few hundred thousand acres of the Oregon Territory, which the two countries had hitherto administered together. And in 1867 Secretary of State William Seward bought from Russia, in what many at the time thought an improvident waste of funds, the nearly 600,000 acres of Alaska.
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Most relevant here, though, is the treaty signed in February 1848 in the northern Mexico City neighborhood of Villa de Guadalupe Hidalgo—a town better known today for the basilica built in remembrance of the two apparitions of the Virgin said to have been seen by a sixteenth-century Indian convert. Today the basilica is by far the holiest place in all Mexico and a destination as important for all the properly pious of Latin America as Mecca is for Muslims.

The Treaty of Guadalupe Hidalgo, which formally ended the vicious and bloody Mexican War (which was the first American war to be photographed and covered by newspaper correspondents, and the first fought mainly beyond America's borders), resulted in Washington's eventual ownership and control of some 340 million further acres of western lands. It was a treaty that at last gave the United States clear access and title to the warmer shores of the Pacific Ocean—something that most of today's jet-bound Hollywood lawyers who claim their lives to be “bicoastal” probably seldom stop to consider.
^†