Daily earthquakes in Connecticut in the last week have officials scratching their heads and discussing ways the state can prepare for and respond to the next seismic event. In the past seven days, 11 small tremors have been recorded in the Plainfield area, the Hartford Courant reported.

"So far, we have not found any answer to the question why this particular spot had these earthquakes," Dr. Alan Kafka, director of the Weston Observatory at Boston College and a researcher of East Coast earthquakes, told the Courant. Kafka met with Plainfield officials Friday to discuss the quakes and address residents’ concerns.

Plainfield residents have made more than 300 calls to 911 in the past week, CBS News reported. A majority of the earthquakes have been less than a magnitude 2 on the open-ended Richter scale. The largest quake happened Monday with a magnitude of 3.1 to 3.3, which is enough to be felt by people but rarely causes damage, the U.S. Geological Survey said.

No injuries from the earthquakes have been reported, and less than a dozen people reported structural damage to buildings, such as cracked foundations, Plainfield Fire Marshal Paul Yellen told the Courant Friday.

Scientists are unable to determine the route of the rumblings because the quakes are too small to rupture the earth’s surface, which would have allowed officials to locate the epicenter. Rob Williams, a geophysicist at the U.S. Geological Survey, told the New York Times Connecticut’s seismic activity appears to be an earthquake “swarm,” in which an area experiences a rapid succession of many earthquakes in a short period of time. Williams said swarms are fairly common geological events and are not precursors of something worse.

This is not the first time the northeast has experienced earthquakes, which occur when underground plates move against each other and release energy that produces seismic waves into the Earth’s crust. A slew of 38 minor quakes rattled Bar Harbor, Maine, from late 2006 to early 2007.