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RE: Bias? Fishiness?
By StevoLincolnite on 5/25/2010 12:08:39 PM , Rating: 2
There's also this idea that the longer we go, the worse it will be.

That's because Earthquakes caused by tectonic stress DOES get worst the longer we go without one, as the stress increases and increases over time leading to a larger Quake.

RE: Bias? Fishiness?
By DesertCat on 5/25/2010 12:45:39 PM , Rating: 2
That's very much the case. We have some understanding of the mechanism that leads to earthquakes in the area. While we look at recurrence intervals for earthquakes to help in prediction, this is not simply a random phenomenon. Pressure is building where the Juan de Fuca Plate is locked with the North American Plate and the elastic limit of the rock will be reached sooner or later.

What Goldfinger and his colleagues have done is help show that Cascadia operates in sections instead of as a continuous feature. At one time there were fears that this fault zone would unzip from southern Oregon all the way to B.C. Canada. Now it appears that it behaves in a more segmented fashion. By understanding which sections are at the most risk, authorities can better concentrate preparedness and engineering resources to those areas first.

In the big picture, it has only been within the last ~20 years that Oregon and Washington have come to understand the potential for a 8+ magnitude earthquake. Oregon has started the process of retrofitting public buildings so that they do not collapse during a large quake, but that takes time and money (much less if the building is designed that way from the start). The schedule for all of Oregon's public schools to be finished with eq retro-fitting? The year 2032. Since it now appears that the southern section has a greater probability of having an earthquake in the short term, one would hope that funding would be concentrated there first.

Oh, and the vertical evacuation idea for tsunamis is being pursued in many seaside towns where no high ground (50+ feet above sea level) is nearby. Given the proximity of the Cascadia fault to the shoreline, residents have about 25 minutes from the time of the earthquake until the first tsunami wave hits. As a result, other options need to be considered. If I remember right the structure in question is the town hall, which will serve as something of a life raft in the case of a tsunami event.

