"I think is not that a 9.0 quake could hit here, everyone assumed that, but that the 9.0 could go on for 4-5 minutes: to this point most predictions were for shorter duration quakes, a minute or so of shaking."

I don't know why people would think that after the 1964 Anchorage Earthquake. It was a 9.2 and lasted between 3-5 minutes (a quick search couldn't pin it down).

"...should we continue to build structures and infrastructures on land that will be thoroughly liquified by a quake."

Several posters here have pointed out the dangers of being in the S. Seattle area if a strong quake hit in the right place. The area is very susceptible to liquification. Right now, there is a fight to replace the existing elevated viaduct (same construction as the viaduct that collapsed in San Francisco in the 1989 Loma Prieta quake), and replace it with an UNDERGROUND TUNNEL! Right on the edge of Elliott Bay.

Unfortunately, the decisions are made by the same people who stand to make the most money. They aren't going to live there, they aren't going to work there. They don't mind setting up thousands of faceless strangers to die. They can look at the info provided by geologists and other scientists, and sweep it aside. If they take down the viaduct and build the tunnel, there is suddenly going to be a rather large patch of prime new real estate available in Seattle. And that's all they're looking at.

Science vs. Greed. And which do YOU think will win?