if it's any help, I picked up the 3.0 mag quake at Fort William, 
Scotland on the 10th of December.  I'm probably about 150 Km away, see 
http://www.earthquakes.bgs.ac.uk/recent_events/20051210232129.9.html 
(I'm just to the right of Edinburgh, having fallen off the map!).

I have a single, vertical 4.5 Hz geophone and got a very respectable 
trace from it.  I would agree, though, that life is more "exciting" with 
a long period device, like a Lehman, unless you live "on top of a 
volcano", as I used to do. 

Cheers

Ian
http://www.iasmith.com/realtime.htm

Jón Frímann wrote:

>Hi all
>
>What is the estimated range of 4,5Hz Geophone to detect earthquakes,
>three axis ? Then i am counting in kilometers.
>
>Regards.
>  
>
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)