Seattle South

Hi everyone, thanks for coming here by clicking your mouse on this page or by accidentally coming here via Google or some other lesser search engine. Welcome to Seattle South! In the parlance of today, most refer to this place as San Francisco, but after record rain in March where it has rained every damn day, I've decided to give us a more appropriate moniker.

Actually, apart from the rain, there is some really interesting stuff going on here in San Francisco Seattle South. This year is the 100th anniversary of the Great '06 Earthquake. Today, the Chronicle has posted a story on the geolophysicists that simulated the 1906 earthquake (view the actual simulation here). The results made my knees buckle:

Less than 4 seconds after the ground ruptured off San Francisco's coast on April 18, 1906, much of San Francisco was destroyed. The great quake that struck before dawn that day savaged the entire Bay Area within 30 seconds and ripped the Earth's surface for 300 miles along the San Andreas Fault at speeds up to 13,000 mph.

For the first time, scientists have re-created in extraordinary detail what happened to the Earth's quiet surface that spring day nearly a century ago.

A new computer simulation of the quake's ground-shaking violence overlayed on today's Bay Area -- and from Cape Mendocino in the north to San Juan Bautista in the south -- offers scientists, engineers and disaster workers the ability to predict where the ground will shake most severely. That knowledge will help engineers design safer buildings and guide first responders as they decide where best to focus their efforts.

...The scientists will display the full reconstruction of the great quake's ground motions along all 300 miles of the fault during a major international conference starting in San Francisco on April 18, but Tuesday they released a vivid computer-created video showing in ominous colors of red, orange, yellow and blue how another big quake with a magnitude of 7.8 or 7.9 -- the estimated size the 1906 temblor -- would affect the Bay area and the delta region as far as Sacramento.

The video, based on a new three-dimensional model of the San Andreas and other nearby faults, shows precisely where the San Andreas Fault first ruptured 6 miles beneath the ground and 2 miles west of the city's coast.

It also shows how the quake's intensity ranged from moderate to shattering throughout the region as the ground ruptured with unbelievable speed.

Research geophysicist Brad Aagaard headed the teams of scientists from Stanford, UC Berkeley, the Lawrence Livermore National Laboratory and URS Corp., a Pasadena engineering firm. Together they created the impressive demonstration of a large quake's capacity to shake the ground in every direction.

Aagaard said he and his colleagues used invaluable data from the first group of scientists who began studying the 1906 quake only three days after it struck and who prepared a two-volume report, complete with scores of maps published in 1908 and 1910.

Invaluable too, he said, were models of the quake's behavior developed by geophysicists Gregory C. Beroza and Paul Segall and graduate student Seok Goo Song of Stanford. They determined how the fault behaved along a stretch that runs completely underwater for nearly 100 miles north of Point Arena in Mendocino County to Cape Mendocino in Humboldt County.

The quake's speed was "phenomenal," Aagaard said.

It took only 90 seconds to hit Cape Mendocino in the north and 54 seconds to strike San Juan Bautista to the south before it petered out, Aagaard said.

"I'd be under the nearest table the second I felt the first shudder," Aagaard said.

There's little to match the fury of the Earth when it's pissed off.