University experts explain recent earthquakes in Connecticut
Photo Credit: Stuart Rankin
Amy Kulikowski – Special to the Southern News
The recent earthquakes in the Eastern Connecticut area have spurred interest and worry in locals. However, according to the Weston Observatory at Boston College, the highest magnitude earthquake detected was 3.1 in Danielson, which is considered minor.
The Observatory accounted for 11 minor earthquakes between Jan. 8 and Jan. 15. Jennifer Cooper of the Earth Science department, explained metamorphic rocks are found in Danielson and surrounding areas where the earthquakes occurred. Locals in Connecticut are aware that earthquakes are not typically common, and the 11 earthquakes that occurred within an eight day period has caused some alarm on social media.
Cooper said Connecticut is ultimately away from plate boundaries, and most significant earthquake activity is being associated with plate boundaries.
“Connecticut is basically in the middle of the plate,” said Cooper, “and it’s common to see in the middle of the plate that the rocks themselves will have fault systems that run through them, which represents zones of weakness.”
Cooper defines these small frequent earthquakes as intraplate earthquakes, which are essentially opposed to being located on edges of plates.
Cynthia Coron, earth science professor, puts together the exhibit for the Connecticut Science Center and maps seismically active faults in Connecticut.
Coron said most of the continental margins are accreted of large scale plate tectonic processes, like pieces of a puzzle, and that even though putting those pieces together may have ended 200 million years ago, there is still adjustment that goes on. Silver faults or a series of them are possible, or two terrains that are minutely shifting relative to each other.
“The reasoning for this activity,” said Coron, “is because old boundaries and silver faults are reactivated under the new stress regime which is created by spreading the Atlantic Ocean. Features that date back billions of years can still shift slightly, generating very low magnitude earthquakes.”
Intraplate earthquakes are not unusual, and happen without any proximal cause without causing any terrible damage. Coron said, “I think the bottom line is that people do not need to be afraid of this; it is not abnormal and not related to a major fault that could trigger a bigger one.”
Coron is from Moodus, Conn., or otherwise known as “place of bad noises.” Before settlers had come to America, the Native Americans gave the town this name because of the rumbling sounds they frequently heard.
Later on, the noises were attributed to natural causes such as seismic activity and in the 1980’s they were declared to be the result of shallow earthquakes, which explains the recent activity in the Eastern portion of the state.
Robert Flanagan of the geography department recalls back to 1981, when in the middle of the day he felt a building shake. Initially, Flanagan said he thought it was a construction site, but to his surprise, an earthquake had taken place right in Waterbury.
Flanagan is not worried about the eastern side of the United States. However, he said, “I’d be interested in the seismic activity that might be taking place at the same time on the west coast. I know it’s a different plate, but I’d be wondering if there is miniscule activity taking place.”
Being a geographer, Flanagan is concerned about the west coast and the urban environments collapsing. “Forget about the physical or built environment because there’s insurance, I worry about people losing their lives.”
As for any worry about a major earthquake following these multiple small ones, professionals of the Earth Science and Geography departments have assured that Connecticut will be just fine.