If you check recent earthquake lists you will see that there have been quite a few relatively low intensity earthquakes lately in the Puerto Rico area. It appears that they largely got started with the following more powerful ones.

2011/12/17 06:09:09 18.172 -67.371 17.0 5.3 Puerto Rico Area
2011/12/17 06:06:12 18.188 -67.370 14.0 5.1 Puerto Rico Area
NEIS Data

Lately, my forecasting charts have been showing strong line peaks in the 67 W area. And I thought that there might be a problem with the charts or that they could be pointing to some volcano activity around 157 W in Hawaii. My computer programs regard longitudes that are 90 and 180 degrees to the east or west of one another as being largely the same with regards to the types of calculations the programs do.

However, those Puerto Rico earthquakes now suggest that the programs might actually have been producing accurate data after all.

Because the standard versions of my programs preferentially favor longitudes where large number of earthquakes have occurred since the beginning of 1990 they are especially likely to point to the 67 W area. Earthquake database line # 15 on the chart below indicates how many earthquakes there are in my database file that occurred at different longitudes. And as can be seen, there were quite a few around 67 W.

Remember that this chart will change as newer versions are stored on my Web site.

There is quite a bit of earthquake forecasting and earthquake research activity underway at the moment. More later on those efforts.