Hi EQF. The crustal deformation sites currently in use in the Philippines cover a very small area. They are essentially the same as those being used in California. Don’t remember the exact location at the moment of those in the Philippines.

They do however have a good number of GPS sites, which have been put to good use. Most of them are on site recorders though which means someone has to go to the site and take the recordings.

What they have learned is that the region from Mindanao, the Philippines to Sulawesi, eastern Indonesia, that is located near the triple junction of three major plates (the Philippine Sea, the Australian, and the Sunda), forms a complicated tectonic deformation zone. From four GPS campaigns since 1997, they have been able to determined crustal velocities at 7 sites in the region. They have found that there is a counterclockwise rotation of the Philippine Islands that is being caused by westward movement of the Philippine Sea with respect to the Sunda.

It’s rather doubtful that they can tell me anything I don’t already know about earthquakes. That is that I know why they occur and how they occur. What I don’t know is the when. I can only speculate about that. Besides when and if I need to know or learn something I have the best source about an hours drive from where I live. The seismologist at the USGS and the University of Berkeley are always more then willing to answer my questions. Take Care…Don in creepy town