EQF-I don't believe that earthquakes could possibly cause a strong regional geomagnetic storm like yesterday (not the same as saying there could not be some local slight effect-I don't know about that). I read that Kp is measured all over, I think North America. Instead, the NOAA page says that things like coronal holes can affect Kp...so, you don't have to have a flare. I don't know exactly what a coronal hole is. Anyway, I'm sure that the spavce weather people know exactly what caused the high Kp yesterday-they just may not always be able to forecast this. Chris