The first earthquake centered in Maine was reported on May 22, 1817. The probable focus was in the central portion, as it was widely felt throughout the State and in New Brunswick. As early as June 11, 1638, a strong earthquake in the St. Lawrence Valley region, near Trois Rivieres, Quebec, was reported felt throughout all the English plantations. Another shock from the same area, in 1663, was felt over all of eastern Canada and the northeastern United States. On November 9, 1727, a violent earthquake near Newbury, Massachusetts, was reported felt from the Kennebec to the Delaware River. Stone walls and chimneys were shaken down in the epicentral region. The famous earthquake of 1755, east of Cape Ann, Massachusetts, was felt from the Annapolis River, Nova Scotia, to the Chesapeake Bay.
On March 21, 1904, a shock overthrew some chimneys at Calais and Eastport, Maine, and St. Stephen, New Brunswick. The total felt area covered most of New England and the Canadian Provinces of New Brunswick and Nova Scotia, approximately 150,000 square miles. There were several light shocks near the origin a few hours after the main earthquake.
An earthquake on December 11, 1912, affected an area of approximately 20,000 square miles and reached intensity V - VI in the Bangor area. On August 20, 1918, damaged to chimneys in South Paris and Norway, Maine, resulted from another shock; felt reports were received from Bridgton, Cape Elizabeth, and Lewiston.
Another strong earthquake in the St. Lawrence River region on February 28, 1925, produced an extensive felt area covering eastern Canada, all of the northeastern United States, points south to Virginia and west to the Mississippi River. The total affected area of two million square miles makes the shock among the most widely felt earthquakes in North America. Estimated at magnitude 7.0, this tremor caused considerable damage at distances up to 200 miles from the center. Intensities reported in Maine ranged from a V - VI at Portland, and IV at Eastport, Greenville, and Orono.
In 1929 a magnitude 7.2 earthquake occurred on the Grand Banks of Newfoundland, about 250 miles from shore. A submarine slide triggered by the earthquake caused the fracture of 12 trans-atlantic cables. In each case they were broken at several points. A tsunami resulting from displacement of the ocean floor caused considerable damage and the loss of 27 lives at Placentia Bay, Newfoundland. Small seawaves were recorded along the east coast of the United States as far south as Charleston, South Carolina. The area of maximum intensity in the United States was the southeastern half of Maine, where clocks stopped, articles were shaken from shelves, and many people were alarmed. The total area affected in the United States was approximately 80,000 square miles.
An earthquake on January 14, 1943, centered near Dover - Foxcroft was reported felt over 50,000 square miles, including all or parts of the New England states. A shock on October 4, 1949, affected about 16,000 square miles in central and southwestern Maine and a portion of northern New Hampshire. St. Johnsbury, Vermont, also felt the tremor. Maximum intensity V reported in southwestern Maine included breaking of dishes, fallen knick-knacks, and displaced pictures.
The Portland area suffered minor damage from an April 26, 1957, earthquake centered about 20 miles offshore. A few cracked walls and some plaster cracks at Portland and split chimneys, broken windows and dishes at Westbrook were the most significant effects. The 6:40 a.m. shock awakened many residents over an area of 31,500 square miles of Maine, Massachusetts, New Hampshire, and Vermont. One city in northern Connecticut also felt the tremor.
Abridged from Earthquake Information Bulletin, Volume 5, Number 3, May - June 1973.
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