Maine Geological Survey officials announced Tuesday afternoon, May 3, that a number of small earthquakes have occurred the past few days in the Belfast, Bucksport, Searsport area.

As many as 30 small events — collectively, referred to as a swarm — have occurred, all measuring less than 2 on the Richter magnitude scale, said Dr. Robert Marvinney, Maine state geologist and director of the Maine Geological Survey, under the Maine Department of Conservation.

“This swarm may continue for several days, but there is no need for alarm,” Marvinney said in a press release from the Maine Department of Conservation.

“This type of swarm has occurred before in Maine. While local residents may feel these earthquakes because they occur only a few miles below the surface, they are well below the magnitude 5 threshold at which damage might occur.”

Marvinney said the occurrence of the swarm is not an indicator that a larger, potentially damaging earthquake will occur.

“Earthquakes are not something that Mainers think about a lot,” said Rob McAleer, Maine Emergency Management Agency director. “This earthquake swarm reminds us that we need to understand Maine earthquakes as part of preparing for all the hazards we face here.”

According to the press release, the Maine Geological Survey, Maine Emergency Management Agency and the New England Seismic Network are monitoring the situation and will provide updates, as necessary.

The Richter scale is a logarithmic scale measuring the amount of energy released by an earthquake. An earthquake that measures 5.0 on the Richter scale, for example, is 10 times stronger than one that measures 4.0.

Seismologists at the New England Seismic Network, run by the Weston Observatory at Boston College, have reportedly located eight of the larger events. The locations determined for these earthquakes are approximate, Marvinney said.

A number have taken place between Bucksport, Belfast and Searsport.

Typically, Maine experiences several earthquake events of magnitude 2 or less each year, Marvinney said.

“These occur in response to the movement of large, rock plates that make up the earth’s crust, even though Maine is not near a plate boundary, where most of the large events occur, such as California and Japan,” said Marvinney.

“The crust in Maine is still adjusting to the loss of thick ice at the end of the last ice age, and this may be a cause for some earthquakes.”

Marvinney noted similar previous swarms:

• In the Bar Harbor area in 2006, about three-dozen earthquakes occurred, including one magnitude 4.2 event and two magnitude 3 events. These were much larger events than in the current swarm, and caused minor rock-fall damage.

• In the Augusta area in 1967, at least 12 located events occurred; many smaller events were likely not detected. The largest event in that sequence was 3.9.

Additional information on these earthquakes can be found at: http://aki.bc.edu/quakes_recent.htm

Anyone feeling earthquakes may report the occurrence to the Maine Geological Survey at mgs@maine.gov

McAleer said MEMA recommends residents take the following preparedness steps for earthquakes:

• Check for hazards in the home;

• Identify safe places indoors and outdoors;

• Educate oneself and family members;

• Have disaster supplies on hand;

• Develop an emergency communication plan.

More information on earthquake preparedness is available at Maine Prepares at maineprepares.com

The direct link to the earthquake information article, “Earthquakes: What You Should Know,” is maine.gov/mema/prepare/prep_display.shtml?id=197853

A large-format “Earthquake Awareness” brochure is available from MEMA by calling 1-800-452-8735 to request a copy.

For more information about the Maine Geological Survey, go to maine.gov/doc/nrimc/mgs/mgs.htm

For more information about the Maine Emergency Management Agency, go to maine.gov/mema/

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