Experts mystified by Plainfield’s earthquake ‘swarm’
Plainfield - The 11 earthquakes that have shaken the town since Jan. 8 are the first known to have occurred there in more than 375 years of historical records, and present seismologists with an "intriguing enigma" they are eager to study.
So said Alan Kafka, director of the Weston Observatory at Boston College, during a presentation Friday night to about 800 residents gathered in the high school auditorium for a public information session about the earthquake "swarm" that last rattled the town Thursday morning. The strongest of the quakes hit Monday morning, measuring 3.1 on the Richter scale. Another measurement put it at 3.3. No major damage or injuries have been reported from the quakes.
"This is the first case of known earthquakes in this part of Connecticut dating back to 1638," Kafka said. "Seismologists don't know why these earthquakes decided to happen at this place at this time, but from now on you will be seeing a lot of us. You have become for eastern seismologists a famous place. From now on we are going to think of the Danielson-Plainfield area as holy ground."
As part of its research, scientists from his office this week set up four portable seismographs in and around the epicenter of the strongest quake.
http://www.theday.com/local/20150117/experts-mystified-by-plainfield-swarm
There is no fracking in this region. The rock is igneous, dating back to the collision between Europe and North America.