Hi, This may be of interest. For the last three weeks one of my stations channels is an ELF detector (au4). It was set up to confirm or deny some magnetic effects that I observed from a fluxgate magnetometer. But in the process the device has captured some tantalizing traces that may be associated with large quakes. Basically what Charlie Plyler has suggested. See www.elfrad.com Anyhow a good example of such a trace has been sent to the event files. 000704a.au4 on the 7/4/00. It shows increased activity some 4.6 hours before the mb5.4 Honshu quake. Similarly but with less intensity an increase of activity occurred some 2.6 hours for the Honshu Mb6.1 event on the 7/1/00. Maybe the less intensity quake has a better signal due to some heating effects from the previous quakes. Maybe? Also from the Chile earthquake (Mw6.4 6/16/00 7:55:35 UTC) there has been some amazing ELF radiation matches. There appears to be ELF detection as various phases bounce through the same active area 120 km below the surface. As there are no "P" and "S" arrival times the station recorded the event as it happened. So far I've been waiting for another big quake in Chile to confirm these readings. One thing, I get the impression that the deeper quakes show better traces. I would be interested in any views. I for one, believed that ELF radiation would be local to an event, if detected at all. Maybe i'm wrong, I have been known to be. Arie Ps: The file 000704a.au4 is 8 hours long. __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>