In a conference room on the second floor of McCone Hall at UC Berkeley sits an old-style seismograph with a mechanical pencil, ticking away as it marks tremors on a roll of white paper. Across the hall sits Peggy Hellweg, operations manager of the Berkeley Seismological Laboratory.
On duty: We collect and provide data, report on earthquakes in Northern California, and train new seismologists and do research with the data that we collect. Our funding comes jointly from the federal government and the state, with some from the university.
On education: I grew up in Lafayette. I studied physics at UC San Diego. I needed a part-time job and got a job with a group of seismologists who needed a programmer. I was learning the science behind the programs I was writing, and that was seismology.
On semantics: The difference between geophysics, of which seismology is a part, and regular physics, is that we seismologists don't have a lab to do experiments in. We get what the Earth gives us.
On equipment: That thing across the hall (seismograph) is only for show now. For the earthquakes we are interested in measuring, we'd need a roll of paper that is 3 miles across. Three-mile-across paper is not very convenient. We use computers now. I can display it on my screen.
On data: What you see on the paper and on the screen is data that comes from a station that was built in the 1960s in a tunnel in the Berkeley hills. It goes down to a data center then comes back up analog to the paper and digital to a program on the screen. With the equipment that we have, we can measure earthquakes on the Hayward Fault. But we can also measure a magnitude 4.5 earthquake in Japan or Tonga or India.
On location: At Memorial Stadium, we had a steel bore hole 400 feet down with wires that came up and went into a data logger box. Our recording equipment was in the north tunnel. It's basically inside the Hayward Fault. When they retrofit the stadium, they lost the bore hole. Our stuff was unrecoverable. So now they've drilled us a new bore hole at the stadium, just up the stairs from the main entrance. It's probably 500 feet down and there is a steel lid on it.
On registration: Nobody wears a pager anymore, but I do. Today, at 3:37 in the afternoon my pager went off with a magnitude 3.8. I was in a staff meeting when it went off. I said, "It's offshore of Eureka. It's not too exciting."
On excitement: Two years ago, in October, there were a couple of earthquakes that happened right here under campus, magnitude 3.9 and 3.8. One happened at about 8 in the evening during the Paul Simon concert up at the Greek Theatre. I was there sitting on the grass and got hit in my butt. A lot of people felt it. I wasn't worried. 3.8 is big enough to feel, just a little shake.
On study: There were more big earthquakes in the last 12 years than in the 12 years before. We are in an era with lots of big earthquakes. Is that significant? It's an interesting historical problem.
I'm interested in the details. Why are some earthquakes big and why are some earthquakes small?
On safety: This building (McCone Hall) is rated "life safe" only. That means I'm supposed to be able to get out with my life, in case of an earthquake, but I may be damaged by ceiling tiles that fall on my head.
- Sam Whiting, swhiting@sfchronicle.com
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