BAR HARBOR – Warm weather is not the only natural phenomenon that seems to be lingering on Mount Desert Island.

A series of earthquakes centered on or near the island that began in September also seems to be persisting.

Another tremor was felt Monday, rattling offices at the town’s public safety building and at The Jackson Laboratory, among other places.

John Ebel of Boston College’s Weston Observatory said initial estimates of Monday’s quake indicate it had a magnitude of 2.3 and was centered 2 1/2 miles southeast of Bar Harbor in Frenchman Bay.

Shasta Philpot, a dispatcher with the Bar Harbor Police Department, said she was on the phone when she felt the floor shake around 2:50 p.m. She said she got a few excited calls after the rumbling but that no one reported any damage.

“Everyone’s been asking if it was an earthquake,” Philpot said.

At Acadia National Park headquarters on Eagle Lake Road, the tremor was detected by different means.

“We heard it,” park dispatcher Allen Moyer said. “It was the same kind of rumble we heard last time.”

That most likely would have been sometime in early November, when a 1.3-magnitude quake on MDI was measured by Weston Observatory, the facility that tracks seismic activity in the Northeast on behalf of the U.S. Geological Survey.

Other local tremors detected by the observatory include a 2.3-magnitude tremor on Oct. 22, a 4.2-magnitude rumble on Oct. 3, and a 3.4-magnitude quake on Sept. 22, according to the observatory’s Web site.

Magnitude measurements represent the strength of earthquakes as calculated by seismographs, which detect and record ground motions. Magnitude is measured in exponential increments. So a difference of 1, from 3.5 to 4.5, for example, represents a tenfold increase in strength.

Magnitude 4 earthquakes are capable of causing moderate damage, while those measured at magnitude 5 can cause considerable damage.

Monday’s rumble seems to have been centered on the eastern side of Mount Desert Island. A dispatcher with the Southwest Harbor Police Department said Monday that police there had not felt anything or received any calls about an earthquake.

Moyer said an Acadia ranger was heading out Monday afternoon to see if the most recent quake caused any damage in the park.

The Oct. 3 tremor, which is believed to have been felt as far away as New Hampshire and on Long Island in New York, sent boulders tumbling onto the Park Loop Road and caused rock slides that led to the closing of the park’s Precipice, Homan Path and East Face hiking trails on Champlain and Dorr mountains.

Ebel, director of Weston Observatory, said that Monday’s 2.3-magnitude quake was an aftershock from the stronger quakes felt earlier in the fall. Monday’s tremor was not strong enough to cause any damage, he said.

Normally, aftershocks following an earthquake become less and less frequent as time passes, Ebel said. There is no way to determine, however, whether the tremors in and around Bar Harbor will continue.

“How long they will last we cannot tell at this time,” Ebel said.