Thanks for the interesting posts, Chris. Just to clarify regarding the "Istanbul early warning" (system?), it seems to me that the system you describe is fundamentally different from those in existence in Japan, and Taiwan, and being proposed for the Los Angeles region and also Mexico City (vis-a-vis west coast quakes). The Istanbul system is not specifically designed for early warning (its purpose being to provide data for post-quake response), and uses accelerometers only, and without signal processing. The latter systems are specifically designed for early warning, and use rapid computer processing of data from seismographs (particularly P-wave information (?) which, if I am not mistaken, would barely register on seismographs).

I believe the systems designed for early warning are a little speedier getting the warning out, primarily because they do not have to wait for the strongest shaking to develop. Apparently the data processing has gotten extremely fast!

Please feel free to correct me if I'm mistaken on any of this.

Mike Williams in Arroyo Grande, CA USA