Reasearch spotlight in the January 4 EOS highlights an article in JGR solid earth that there were fewer small quakes in the 4 years before a M8 quake in 2003 in Japan (subduction beneath Hokkaido). It also says that this sort of quiescence has occurred prior to "several other earthquakes"

This seems to be the opposite of what the other article is saying about Tokyo. Well, maybe not the opposite, but very different logic?

I would wonder whether a Great quake beneath Puerto Rico and Virgin Islands would be preceded by quiet, or increase, or neither. I have posted before that I was curious whether the swarms you see near Puerto Rico and Virgin Islands occur on other subduction zones: only USA areas including these have all quakes >2.5 listed on the USGS catalogue, so swarms of 3s in other regions would not show up on this list.

Chris