Question for today...do small plates "twitch"? How small? What about 100 km-scale fault-bounded crustal blocks in California? If there is an earthquake on one side, can it cause a little twist or rotation that sets off a quake on the other side? There was a M6.0 quake south of Guadeloupe early today...that is the opposite side of the Carribean plate from the M6.2 in Costa Rica, and 27 1/2 hours later...but this plate is not so small, so the distance between is large.The Costa Rica quake was a shallow oblique normal slip...not part of the subduction motion there. The depth of the Guadalupe quake is also shallow, but they have not put up a focal mechanism yet so I don't know what the slip is...The depth may be incorrect...Costa Rica's was "set by location program"

Chris