Cathyryn..It depends where the earthquake initiates...if it breaks first in western Marmara Sea and propagates east, it could be 20 seconds...but I'm not sure because I did not ask that question. The director said something about just a few seconds. I also did not ask what would be done with such a warning. I doubt it would go out to the public. But, certain things might be shut down. I think this type of warning in Japan might be used to stop the high-speed trains. Such a system has at least been talked about in California: John...do you know if it has been set up? For example, an earthquake starting on the southern San Andreas and propagating NW...Kim Olsen's simulation show long duration strong ground motion in L.A....with quite a long warning being possible (30 s?). I downloaded that simulation and could look at it again...but don't feel like it..
Chris