Interesting.

I have no idea if this is at all relevant to the recent activity in Taiwan, but there was a 4.9 earthquake on the Northern Marianas island of Agrihan yesterday. Agrihan is a small island which is just the crown of a massive volcano sticking out of the ocean.

This area sees very little seismic activity, but occasionally it has massive earthquakes. A few years ago an 8.1 hit Guam. It was the largest earthquake in the world that year.

I've been watching this site: https://earthquake.usgs.gov/earthquakes/map/. It defaults to a view of North America but you can zoom out to a world view.