AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Will we ever see quake 512/18/2023 ![]() Some of the simplest questions about earthquakes remain hard to answer. And yet scientists still can't say when an earthquake will happen. Plate tectonics may be one of the signature triumphs of the human mind, geology's answer to biology's theory of evolution. A century later, we have a highly successful theory, called plate tectonics, that explains why 1906-type earthquakes happen-along with why continents drift, mountains rise, and volcanoes line the Pacific Rim. It's been a hundred years since the last big one in California, the 1906 San Francisco earthquake, which helped give birth to modern earthquake science. Earthquake faults have a nasty way of combining patience with impulsiveness. You see right there a fundamental problem with earthquakes: They refuse to operate on human standard time. The players are worried about making the team. It's a hot summer day a few weeks before the start of the season. "In an earthquake," says Allen, "the entire field may liquefy." They'd just get knocked off their pins-tackled by a temblor.īut of course no one on that field is worried about an earthquake. Much of the stadium is built on soft ground, the kind that amplifies seismic waves. It hasn't spawned a major earthquake since 1868. ![]() He calls it "Earthquakes in Your Backyard." The name couldn't be more appropriate, because the Hayward is a particularly dangerous fault. They also "break." They "rupture." The creep happens in plain sight, but the breaking, the rupturing, the lurching-the earthquaking-will hit you blindside.Īllen teaches Berkeley's oldest course on earthquakes. What hubris to build a stadium on a fault!īut Allen points out the central problem: Faults don't just creep. ![]() At the rim of the stadium, a Berkeley professor named Richard Allen shows me the result of 80 years of creep: a four-inch (102-centimeter) jog in the concrete, inelegantly bandaged with a rusty metal plate. Scientists now know that the Hayward creeps-it inches along steadily, although millimeters along would be more accurate. ![]() Each half of the stadium could move independently, riding the shifting crust without breaking a sweat. So the architects gamely built the stadium in two halves, shaped sort of like a coffee bean, with a line, the fault, essentially splitting the structure. Earthquake science was still young, but the architects apparently realized that the Hayward is a fault, where two pieces of crust move past each other. ![]() It races downfield, barrels through the south end zone, and keeps going, careening down the street toward Oakland.īack in the 1920s, when architects drew up plans for a grand football stadium at California's flagship university, they refused to let a geologic imperfection stand in their way. One map shows it splitting the goal posts in the north end zone. Then the fault runs underneath the stadium. You can straddle the fault, one leg up the steps, one leg down. It passes under a theater and a couple of dormitories and kinks the concrete steps outside California Memorial Stadium. The Hayward Fault, a long and lethal crack in the Earth, slices along the base of the Berkeley Hills and directly through the University of California. ![]()
0 Comments
Read More
Leave a Reply. |