Nikolai Posted January 18, 2012 Share Posted January 18, 2012 Oh, it was. I know just because of what friends in NY told me. It was one of those big, nonstop stories on the TV news-- before the 24-hr cable news fad-- with a huge, banner headline on the front page of the NYT. It was a big story. The nation's second-largest city was smashed up, paralyzed, and under curfew for days. isn't it still?!?!? Link to comment Share on other sites More sharing options...
Ian Posted January 18, 2012 Share Posted January 18, 2012 i was there. it shook a lot and woke me up Link to comment Share on other sites More sharing options...
Coach McGuirk Posted January 18, 2012 Share Posted January 18, 2012 Wow, it only killed 57. Link to comment Share on other sites More sharing options...
on_wx Posted January 18, 2012 Share Posted January 18, 2012 People are often confused about this topic, so let me explain it: The Richter magnitude is a measure of the total energy released in the event-- not how violent the shaking is at the surface, at a given location. The motion "violence" is measured by the Modified Mercalli (MM) scale, which is what the map in Post 1 shows. While there's a rough correlation between Richter magnitude and MM intensity, it's not a perfect correlation-- so some smaller quakes can produce extremely violent shaking. (Other factors include depth and soil composition.) The Northridge quake (6.7) produced MM IX shaking. The tremendous Chilean quake of last year (8.8) produced the same level of shaking: MM IX. The Chilean quake shook a larger area and lasted longer than Northridge, but it was no more violent than Northridge. So, what we experienced in L.A. in 1994 was just as violent as what Chileans experienced in their quake in 2010. It's just like how two hurricanes can have the same max winds, but one is tiny and one is enormous. The Northridge quake was relatively small (compared to the Chilean quake), but that didn't matter to us Angelenos, because that "small" quake happened right under the city. We had a direct hit; we were "in the eyewall". Thank you. No, you are not off base-- you are basically right. See above. Yeah. Christchurch, New Zealand for example. The September 2010 earthquake at 7.1 caused devastating damage to the city, but nothing like the February 22, 2011 6.3 that collapsed tall buildings and killed 181 people. The 6.3 had peak ground acceleration of 2.2G. In comparison, the Japan 9.0 was 2.7G and the Haiti 7.0 was only 0.5G. While the Christchurch quake was only a 6.3, it felt like an 8 or 9 mag. And I think it's the 2nd most intense PGA recorded, with the Japan 9.0 in 1st place. Link to comment Share on other sites More sharing options...
aslkahuna Posted January 18, 2012 Share Posted January 18, 2012 The World Series Earthquake was the 1989 Loma Prieta one. Interestingly enough, the portions of the San Andreas that encounter the Transverse Ranges and the coastal mountains around SFO both of which force the fault off its linear track results in the fault having a thrust component to its movement-in fact, a surface rupture was never found for the 1989 shock. Then we have the triple point off Cape Mendocino where the San Andreas merges with an E#-W fault which itself intersects the south end of the Cascadia subduction zone. There most any kind of movement and intensity are possible. Steve Link to comment Share on other sites More sharing options...
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