He was calling, he said, to ask if the following winter I might like to move across to San Jose and teach there for a few months. It was, I thought to myself, the most uncannily propitious of synchronicities. And so it is with pleasure that I perform here my first and happiest duty—to record to whoever (or whatever) it was that prompted Professor Rice to call me that day my most earnest and sincere thanks.

  For I did indeed take up the offer: I drove out west and I spent a small part of those first four months of 2004 teaching, lecturing, and generally bloviating to a most intelligent and attentive group of students in California. And then, from the pleasant flat in central San Francisco with which the university supplied me, I spent the rest of my time exploring and riffling my way through the manifold fascinations with which the cities of California, and the disaster that afflicted and otherwise affected them a century ago, are so richly endowed.

  Without the university’s help it would have been all so very much more difficult. I am grateful also to the friends I made at the university: Alan Soldofsky (who is academically fascinated by that most geologically minded of California poets, Robinson Jeffers), Mitch Berman, Paul Douglass, and the delightful Connie Lurie, whose generosity funded my visiting professorship to the university of which she is one of the more stellar alumni.

  GIVEN THE SEISMIC PROPENSITIES of California, it is hardly surprising that so many geologists are drawn there, most hovering as moths around the ever-flickering flame of the San Andreas Fault. They were universally helpful to me, enthusiastically sharing their knowledge and research, and trying hard to keep me from committing elementary blunders—and if I have failed them then it is my failure, not theirs. Many work for or with the U.S. Geological Survey office at Menlo Park, making up what is surely the jolliest coven of bureaucrats within this or any other government—and I happily record my thanks in particular to Mary Lou Zoback and Mark Zoback, Andy Snyder, Carol Prentice, William Ellsworth, and Leslie Gordon. Susan Hough, who also works for the USGS but on the Caltech campus in Pasadena, was enormously helpful, and as a writer of popular geology books also was particularly sympathetic to the challenges of conveying complex seismic matters in an assimilable way: I owe Susan, now a good friend for life, a formidable debt.

  I would also like to record my gratitude to other geologists elsewhere: Eldridge Moores and John Dewey at the University of California, Davis; Tina Niemi, who is an expert in digging trenches into the San Andreas Fault but who is nominally based far away at the University of Missouri in Kansas City; Bill Cotton, who is deeply involved with the geological bizzareries of the town of Portola Valley; Ann Crawford at the Geological Society of America in Boulder, Colorado; Peter Haeussler of the USGS office in Anchorage, Alaska; Ted Nield of the Geological Society of London; Anthony Lomax, whose recent interests from his headquarters in France include new research on the location of the 1906 earthquake’s hypocenter; the authors Damien Nance and Brendan Murphy, who offered me help on the origins of the names of early supercontinents; and John Rogers, who named the first and oldest of them Ur, from his department at the University of North Carolina.

  A brief and unexpected encounter in an elevator in a Dallas hotel with Dave Ruppert, an archaeologist with the National Park Service in Denver, led me to two further Park Service scientists based at Yellowstone, Hank Heasler and John Varley, who helped me understand the significance of the variations in the periodicity of the geysers there. And Fred Ganders, a botanist at the University of British Columbia, advised me on the yerba buena plant and the man who first named it.

  Harold Brooks of the San Francisco office of the American Red Cross, and his colleague on the other side of the Bay, Jean Nickaloff, were both immensely helpful in showing me their plans for dealing with any future citywide disasters; as was Jim Aldrich of the City of San Francisco’s Office of Emergency Services, whose latest plans are necessarily the most sophisticated of all those that have been prepared for the skein of cities that lie between Santa Rosa and San Jose, and which can be expected to suffer the consequences of any dramatic slippage on the various faults that run beneath them.

  I am grateful also to Claire Perry, Curator of American Art at the Cantor Center at Stanford University; to Martin Uden, British Consul General in San Francisco, and his assistant, Julia Cottam, who uncovered original correspondence from the diplomats who were based in the city at the time of the earthquake; to Harold Hallin of Lake Tahoe, Nevada, an insurance underwriter whose syndicate was involved in writing 1906 policies; and to my San Jose student Pat O’Laughlin of Los Gatos, who kindly introduced me to a number of his friends who had papers, images, memories, and opinions related to the seismic history of the region.

  By chance I found that my apartment in San Francisco was just one floor above the flat belonging to California’s most renowned living historian and author, Kevin Starr, and I am happy to record my thanks to him for his many courtesies and for his advice (and for his forbearance whenever I had heavy-footed friends over for tea).

  The staff at Acorn Books was universally helpful in supplying me with long-forgotten publications that related to the 1906 events. I hope they consider that I, as customer, once helped them, too, if in a small way, on that occasion when about six of us felt obliged to jump on and subdue an extremely tall but somewhat deranged gentleman who, after lunching unwisely one day on a cocktail of unfamiliar chemicals, decided to come in and try to wreck the shop. We pinned him to the ground while waiting for the police to come, and—though I hardly recommend it as an ideal way to break the ice between bookseller and customer—we came to know one another extremely well in consequence, and discounts were offered once in a while.

  And, finally, among those who gave professional help, I must give enormous thanks to Ron Henggeler, whose peerless performance as a waiter at the Big Four Restaurant on Nob Hill is matched only by his talent as an artist and his infectious enthusiasm for collecting San Francisco memorabilia. Not a single aspect of Bay Area life—from the debates over the siting of wartime antiaircraft batteries to the menu choices for lunches served at the Sutro Baths, from the mating habits of sea lions to the casualty tolls from earlier earthquakes—has ever escaped Ron’s jackdawlike appetite, and his collections are immense and impeccably organized. He was kind enough to allow me to borrow from almost all and everything he possessed—film clips, books, magazines, paintings, vinyl records—and never once pressed me to return them until I was good and ready to do so. Ron is an enormously proud waiter, as he should be, and for anyone in need of some arcane fact about old San Francisco, I recommend a visit to his restaurant and a seat in his station. But do please remember the pourboire.

  MATTHEW SCHECHMEISTER of Stanford and Amy Biegelsen of Richmond, Virginia, helped with many aspects of my researches, and did so ably and with great energy. I wish to thank my friend Renee Braden of the National Geographic Society archives, together with her admirable colleague Mark Jenkins. Other old friends, Kate Schermerhorn and Matt Clarke, recorded much of my West Coast research on film, in the probably vain hope that one day someone, somewhere, might be interested in seeing just how a book of this kind is made: That they put up with my whims so cheerfully for so long is testament to their undeniable talent as filmmakers. Richard Price of Robinson, Illinois, offered many valuable suggestions for improving the text of the paperback edition of the book; and Steven Marshank of Ashland, Oregon, made some very useful comments that I similarly incorporated into my revision. Sophie Purdy, as is her wont, helped tirelessly with this book, just as she helped with the three that immediately preceded it: My debt to her is incalculable.

  MY SUGGESTION that I write this book was accepted, warmly and eagerly, by that most legendary of editors, Larry Ashmead—and though Larry retired during the writing of it, he never once abandoned his paternal interest in the project. My fondest hope is that when he sees it now, he will feel content with the way it all turned out. If he does, then that will in no small part be to the team that succeeded him—especially Henry
Ferris, the wonderfully capable editor who agreed to take on the project in New York, together with Peter Hubbard, his meticulous assistant. In London my editor, Mary Mount, offered a thousand and one suggestions for improving the text: I believe I agreed with almost all of them, and am grateful to her for making them, and so tactfully and kindly, too. Donna Poppy and Sue Llewellyn remain the most faithful of copy editors, brilliant and faultless; and Peter Matson and Bill Hamilton—helped by their respective assistants Nina Aron and Ben Mason—remain the finest agents for which an author could possibly wish. I raise a glass to each of you.

  As I do, finally, to my partner, Elaine, who came to hear in a couple of years more about strike-slip faults and ophiolite sequences and the Chinese poetry of Angel Island than any person of reasonable firmness might expect to hear in a couple of lifetimes. She took it all with great good cheer and in a spirit of amused tolerance, and remained in the best of good humor all the time that I was hunched silently over my keyboard, ignoring all around me. So for allowing me the peace and for keeping content all the time: a thousand thanks, my dearest Elaine. You’ve been an absolute brick.

  A GLOSSARY OF POSSIBLY UNFAMILIAR TERMS AND CONCEPTS

  ALQUIST-PRIOLO This term, used with easy familiarity by many Californians today, refers to the 1972 Earthquake Fault Zoning Act, which was sponsored by the Democrat state senator for Santa Clara, Alfred Alquist, and the Republican state assemblyman for Ventura, Paul Priolo. The act compelled the state geologist to determine where all California’s geological faults were located; imposed strict limits on the types of buildings that could be erected in seismic hazard zones that ran along them; and in time demanded that maps be prepared showing builders and real estate agents—as well as insurers—which parts of the state were relatively seismically safe and which were likely to be unsafe. Alquist-Priolo maps, as they are known, now run into the hundreds and are essential for anyone thinking of building or buying in the Golden State.

  AMMONITE A slow-swimming creature of the warm and deep Mesozoic oceans, which propelled itself backward by flexing its muscular tentacles and was supported in the sea by a coiled chambered flotation cell, and which resembled in shape the horn of the Egyptian ram-headed god, Ammon. These attractively coiled fossils are found today in great abundance in limestone and shale of the Cretaceous and Jurassic.

  ANDESITE An extruded volcanic rock with a very high silica content and which seems to be involved in highly explosive volcanoes. It contrasts with its much-lower-silica-content colleague-rock basalt, which tends to be found in the more gently oozing volcanoes of the world.

  BORE A riverine tsunami, usually caused by unusually high flood-tides colliding with the estuarine outflow from a powerful stream. Bores can also be caused by earthquakes that strike near major rivers. The word probably has the same Old Norse root as the modern word billow.

  BRACHIOPOD A common bivalved marine creature, found through almost all periods of the geological time scale, from the Lower Cambrian onward. One of their species—Lingula, which can still be seen in modern oceans—has remained evolutionarily unchanged for more than 500 million years. The creatures—often, because of their similarity in shape, known as lamp-shells—are fixed to the seabed by a muscular foot, and they waft extendable feeding devices through the passing seawater currents, trawling for nutrients.

  CABLE As a unit of maritime measurement amounting to a tenth of a nautical mile, or about 600 feet. (A nautical mile, defined as one minute of arc of longitude measured along the equator, is 6,082 feet; a speed of one nautical mile per hour is known as one knot.)

  CLINKER From the Dutch word klinker, from the ringing sound it makes when hit with a hammer, the incombustible residue of a volcanic eruption—a mixture of lava, bedrock, and other debris that often chokes a volcanic crater.

  CONESTOGA WAGON The large covered wagons with which the earliest westbound settlers traveled across the American plains were built in Conestoga, Pennsylvania, a town named after a local Iroquois tribe. These clumsy vehicles had a postilion—a nicety not found in the smaller and swifter wagons that came to be known as prairie schooners—and which most emigrant expeditions favored before the coming of the railways (and which led to the demise of that most sweetly named craft of whiffletree-making).

  CRATON The name given to those immense tracts of the earth’s surface that have remained tectonically stable and seismically inactive for uncountable millions of years. These areas—like much of north central Canada—are composed invariably of ancient shield rock.

  CWM A Welsh word for a mountain valley, still much used in mountaineering vernacular: the Western Cwm on Mount Everest, for example. Its equivalents in France, Germany, and Scotland are the words cirque, Kar, and corrie; despite the limitations of Welsh, only cwm appears to have found wide international acceptance among the climbing fraternity.

  DIP The angle between a geological structure and the horizontal: Sedimentary rock layers are said to be steeply dipping, for example, if they are tilted close to vertical. See also strike.

  GABBRO Basaltic magma (q.v. andesite) that cools slowly, in a pluton (q.v.) and that in consequence assumes a more crystalline appearance and structure than fine-grained basalts themselves

  GAIA AND THE GAIA HYPOTHESIS James Lovelock, a British space scientist now regarded variously as either a visionary or a harmlessly misguided eccentric, first came up with the idea in the 1960s that the earth might be a living entity, a single, highly complex enclosed system. His belief, in essence, held then—and still holds now, after four decades of experimentation and observation—that the Gaia (the word formed is from the Greek word for “mother earth”) is a complex entity that involves the earth’s biosphere, atmosphere, oceans, and soil, “the totality constituting a feedback or cybernetic system which seeks an optimal physical and chemical environment for life on this planet.” Through Gaia, says Lovelock, the earth sustains a kind of homeostasis, the maintenance of the relatively constant conditions that exist upon its surfaces.

  GNEISS A coarse-grained metamorphic rock, marked by foliations of alternately dark- and light-colored mineral bands. Even more foliated rocks that readily split into slatelike slabs are generally called schists: the two types of rock are frequently found together.

  GRABEN When two faults—not strike-strike-slip faults, like the San Andreas, but the more common vertical or near-vertical faults—occur close by and approximately parallel with each other, and the land between them drops, then the resulting valley is known as a graben. If it rises, pinched upward between two fault lines, the resulting uplifted block is called a horst.

  GRANITE Found essentially only in continental bodies, granite is a slow-crystallizing volcanic rock, invariably cooled in a pluton, and with a substantial percentage of light-colored quartz, as well as feldspar and other minerals in large or relatively large crystalline forms.

  GRAYWACKE A hard, dark, silty sandstone that has been mildly metamorphosed by heat and pressure and is thus rather harder and more dense than other sedimentary rocks of similar constitution.

  INTRUSION The rock mass that results from the invasion of one rock by a molten version of another. Dolerites—dark, fine-grained igneous rocks—invariably form intrusions, known either as dikes, if they invaded vertically and cut across the bedding planes of sedimentary rocks, or sills, if they inserted themselves in parallel, like the igneous ham in a sedimentary sandwich. The Palisades Sill, on the New Jersey shore of the Lower Hudson River opposite Manhattan, is a classic dolerite sill.

  K-T BOUNDARY EVENT The fossil record at the end of the Cretaceous and just before the beginning of the Tertiary, 65 million years ago, becomes suddenly and inexplicably interrupted, and is marked by the extinctions of nearly three-quarters of all the then-current life-forms. There was no ready explanation for what might have happened—until the 1970s, when researchers in Italy detected an anomalous spike in the amount of the rare metal iridium found in a thin clay layer that marks the boundary between the two eras. This—toge
ther with their discoveries of soot and pressure-strained minerals in the clay—led them to deduce that one or more meteors (which produce iridium as a by-product) might have struck the earth 65 million years ago, causing a major catastrophe for all living things. Eventually a meteor crater—the smoking gun—was discovered off the coast of the Yucatán, at Chicxulub, and others were detected off western India, in the North Sea, and in the Ukraine, all from the same period. It now looks very much to believers as though a shower of enormous meteors struck the planet at the end of the Cretaceous—bringing the era to an end and causing infinitely more destruction worldwide than was occasioned by any earthquake, San Francisco’s included.

  NUNATAK This Inuit word denotes a mountain peak rising through or between glaciers or land ice in an arctic environment. In Greenland, where most of the world’s nunataks are to be found, the base rock is invariably basalt, extruded from the mid–Atlantic ridge volcanoes in and around Iceland.

  OOLITH An egg-shaped calcareous particle precipitated in the warm seas of the (usually) Jurassic period and which, once consolidated into rock, forms an attractive and decorative limestone.

  OROGENY A period of mountain formation in which the earth’s crust is deformed by one or more of a variety of processes that include vulcanism, subduction, plate collision, folding, plate divergence, and seafloor spreading or faulting.

  PLATE TECTONICS The fundamental theory of the New Geology, first adduced in the mid-1960s by a variety of geologists and geophysicists working independently around the world. The Canadian J. Tuzo Wilson is popularly credited with first using the word plates in a paper in Nature in 1965. The theory holds that the earth’s lithosphere consists of large, rigid plates that move horizontally in response to the flow of the asthenosphere beneath them, and that interactions among the plates at their borders cause most major geologic activity, including the creation of oceans, continents, mountains, volcanoes, and earthquakes.