An earthquake of Mc = 4.4 occurred southeast of Dixfield, Maine, on May 29, 1983. The event was widely felt in Maine and New Hampshire and caused a maximum epicentral intensity shaking of V(MM). Five aftershocks smaller than Mc = 1.0 were recorded by portable seismographs installed after the main shock. One of the aftershocks was well-located at a depth 2.4 ±0.5 km from the portable seismograph data, while the depth of the main shock was computed to be 1.8±1.4 km from the regional network data. Since the epicenters of the well-located aftershock and the main shock coincided, it is likely that these events originated from the same location. First motion polarities from the main shock suggest reverse motion on north-south oriented fault planes. The earthquakes occurred about 2 km west of the northeast-striking Bald Mountain fault, but they cannot be clearly attributed to that or any other recognized brittle structure in the area.

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