Rescues, fires, weather, roads, trails, water, etc.
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Taco
Snownado survivor
Posts: 6061
Joined: Thu Sep 27, 2007 4:35 pm
Postby Taco »
I almost fell over when I was walking home, didn't know WTF that was. Got home, looks as if someone broke in and just made a bigass mess of everything without stealing anything (except my cat, Bill... can't find him).
Bit of shaking down here in San Diego. Lasted longer than normal, I got up and moved away from my ceiling to floor windows, but nothing fell of shelves, ect.
What we need is a cool earthquake hike. I know their is the Punchbowl hike, but something near Cajon/Devore. There is all those mountains there and canyons, it would be easy to name the hike..."The Big One"...
I was standing in a parking lot in Burbank next to a 6 story office building. I felt nothing...all of a sudden hoards of people started coming out of the building talking about the quake and how bad the shaking was on the upper floors. A few books fell off shelves, and it rattled some nerves.
Meanwhile I felt nothing while standing in the parking lot . Must be my 'drunk' legs.
We felt it real good here in Corona. I was in a 2nd floor conference room doing a design review with a customer. The projector started to shake then the whole building swayed, then everything shook violently. The customers had flown in from New York and never felt an earthquake before but they were really calm and just got under the table. One was even really stoked to have felt a real genuine California earthquake!
Tim wrote: One was even really stoked to have felt a real genuine California earthquake!
lol. Depends on what you mean by real. I live in the SF Valley and remember the Northridge Quake well. I've been through a few named quakes (Sylmar, Whittier, Sierra Madre, and Northridge), but the Northridge quake scared the living daylights out of me. I bet he'd be a lot less stoked in a 6.7 like the Northridge Quake instead of a 5.8! Remember that the scale is logarithmic not linear. Each point on the Richter Scale is 10 times larger than the previous point.
The magnitude of most earthquakes is measured on the Richter scale, invented by Charles F. Richter in 1934. The Richter magnitudes are based on a logarithmic scale (base 10). What this means is that for each whole number you go up on the Richter scale, the amplitude of the ground motion recorded by a seismograph goes up ten times. Using this scale, a magnitude 5 earthquake would result in ten times the level of ground shaking as a magnitude 4 earthquake (and 32 times as much energy would be released). To give you an idea how these numbers can add up, think of it in terms of the energy released by explosives: a magnitude 1 seismic wave releases as much energy as blowing up 6 ounces of TNT. A magnitude 8 earthquake releases as much energy as detonating 6 million tons of TNT.
It was just a moderate earthquake. The Northridge Earthquake was ~13x more powerful if I'm understanding the Richter Scale properly. The Northridge Quake caused bridges to come down, buildings to collapse, and deaths. The Northride Quake was a "strong" earthquake (6 range). I can't imagine what a "great" (8 range) earthquake like the Great San Francisco Earthquake would be like. An 8 quake would be ~100x more powerful than a 6 quake like the Northridge Quake.
The thing about magnitude is that it isn't representative of total energy released respecive to periods of vibration (duration), amplification (ridge shattering, liquifaction etc.) and the projection of various waveforms through heterogeneous soils (localized schists and basin fractures).
Still, it was exciting considering we haven't had a good shaking here since '94.
Jim, I wasn't even born when the Sylmar quake happened ..