I noticed the last couple of days I haven’t seen any of the earthquake registered in the Puerto Rico area on EQView. Also a few north of St Thomas USVI that were not posted by the PRSM & USGS. Is this due to lack of station in our area?
Also just curios how many stations are needed to register a quake in EQView?
Thank you for your message.
Yes, this is a function of station density.
The answer to your question is “it depends” but generally, we need 25 phases for the automatic detection system to register an event. This is to avoid false positives.
Sorry to bring this back up. I still believe there is something going on, I still do not see EQ posting events in our area(Puerto Rico/US virgin island). the last 24 hrs in this area we had a 1 M4.2, 5 M3.x , on 3/29 there was a M3.9 and none are on EQview. back in January I do remember seeing a map similar to Chile with lots of activity and Puerto Rico had less stations,