November 25, 1988 Earthquake: Saguenay, Quebec City, Quebec, Canada

Damage in the Chicoutimi-La Baie area and in the Quebec City area. Maximum intensity VII. Landslides reported in the La Tuque area. Felt in Canada from southern Ontario to Nova Scotia and western Labrador. Felt (V) in parts of Maine, Vermont, New Hampshire and New York. Felt in the New England States and in parts of Indiana, Michigan, New Jersey, New York, Ohio, Pennsylvania, Wisconsin and as far south as Washington, D.C. Depth 19.8 kilometers from broadband displacement seismograms. FAULT PLANE SOLUTION: P-Waves NP1:Strike=340 Dip=63 Slip=90 NP2:Strike=160 Dip=27 Slip=90 Principal Axes: (T) Plg=72 Azm=250 (P) Plg=18 Azm=70 Comment: The focal mechanism is poorly controlled and corresponds to reverse faulting. The preferred fault plane is not determined. RADIATED ENERGY No. of sta: 5 Focal mech. C Energy 1.9+0.8*10**13 Nm CENTROID, MOMENT TENSOR (HRV) Data Used: GDSN L.P.B.: 10S, 25C Centroid Location: Origin Time 23:46: 3.1 0.7 Lat 48.01N 0.07 Lon 71.16W 0.05 Dep 27.5 3.6 Half-duration 3.4 Moment Tensor; Scale 10**17 Nm Mrr=5.16 0.20 Mtt=0.03 0.25 Mff=-5.19 0.24 Mrt=-4.56 0.70 Mrf=1.07 0.50 Mtf=1.17 0.22 Principal Axes: (T) Val=7.83 Plg=60 Azm=183 (N) Val=-1.90 Plg=26 Azm=332 (P) Val=-5.93 Plg=14 Azm=68 Best Double Couple:Mo=6.9*10**17 NP1:Strike=189 Dip=39 Slip=135 NP2:Strike=317 Dip=64 Slip=60

Damoge in the Chicoutimi - Lo Baie area ond in the Quebec City area. Moximum intensity VII. Landslides reported in the Lo Tuque area. Felt in Canada from southern Ontario to Novo Scotia and western Labrador. Felt (V) in parts of Maine, Vermont, New Hampshire and New York. Felt in the New England States and in parts of Indiana, Michigan, New Jersey, New York, Ohio, Pennsylvania, Wisconsin and as for south as Washington, D.C. (reference #1053)

1988 November 25, 23:46:04.38 UTC, 48.047 N 71.315 W, magnitude 5.83 Mw (reference #10476, v.10)

The mainshock was felt on Cape Breton Island to the east, in Labrador to the northeast, along the southern shore of Hudson Bay to the northwest, along the northern shore of Lake Superior to the west, and in Indiana and Virginia to the southwest. All of New England and the Middle Atlantic U.S. states reported feeling this earthquake […] The 1988 earthquake appears to have taken place at the southern boundary of the Saguenay graben, a valley that down-dropped about 575 million years ago when ancestral North America started to rift away from a continent to the east […] There was some notable damage to unreinforced masonry structures due to the shaking of the 1988 Saguenay earthquake. The epicenter of this earthquake was about 22 miles (35 kilometers) south of the Quebec towns of Jonquiere and Chicoutimi, and Saguenay was about 25 miles (40 kilometers) from the epicenter. Almost all of the damage in this area was confined to walls made of unreinforced brick, cinderblock, or stone. Several schools suffered cracks in masonry walls, and at one secondary school in Chicoutimi, the tops of some cinderblock divider walls fell, destroying the suspended ceilings and littering the floor of the school with debris. Fortunately, no one was hurt by the failures of these walls because the school was unoccupied at the time of the earthquake. In Chicoutimi, the earthquake shaking caused significant cracking in some walls in the provincial government building, and at La Baie the police and fire stations sustained cracks to a nonstructural masonry wall. In addition to this masonry damage in the area near the epicenter, for a bridge across the Saguenay River, the earthquake shaking caused the plate of one of the bridge’s girders to separate from the abutment on which it was installed. Also, in Jonquiere two pipes carrying natural gas were damaged, which led to fires from the leaking gas […] There were some deaths and a number of injuries reported following the 1988 Saguenay mainshock. The November 26, 1988, issue of the Globe and Mail in Toronto, Ontario, reported that one man died of a heart attack at a restaurant in Quebec City during the earthquake shaking. The November 26, 1988, issue of the Boston Globe of Boston, Massachusetts, contained a report that there was a traffic fatality in Quebec City that occurred at an intersection where the traffic lights were not working due to the loss of electricity in the region. The November 27, 1988, issue of the Boston Globe indicated that following the earthquake about 50 persons were treated for minor cuts and bruises at Chicoutimi, Quebec. (reference #13657)