March 6, 2005 Riviere-du-Loup Earthquake
Widely Felt Across Maine

The Geological Survey of Canada reports that an earthquake occurred at 1:17:49 a.m. Eastern Standard Time on Sunday, March 6, 2005 near Riviere-du-Loup, Quebec, on the St. Lawrence River about 95 miles northeast of Quebec City. It was felt widely across Maine and as far south as Boston. No damage was reported.

The following parameters have been calculated for the earthquake:

Magnitude 5.4 (Nuttli, 1973)
Location 47.75 degrees North latitude, 69.73 West longitude
Depth 13 kilometers
This places the epicenter about 63 miles north-northwest of Fort Kent, Maine.

Felt Reports

Many people across the northeast region submitted felt reports to the U. S. Geological Survey in Pasadena or to the Maine Geological Survey through their on-line web sites. Shaking in northern Maine was at intensities III to IV (weak to light), and reports from southern Maine were mostly at intensity II, according to the Modified Mercalli Intensity scale. The USGS data are automatically posted by zip code on an intensity map.

The MGS reports are reviewed by a geologist and assigned MMI values. The results are listed by town below.

Reports from 284 people who felt the earthquake in Maine are tabulated below. The columns are as follows:

  • Town. Listed alphabetically as reported by the submitter.
  • MMI = Modified Mercalli Intensity (given in Roman Numerals). For the U.S. Geological Survey data, these values are determined automatically by an algorithm described at their web site. For the MGS data, these values are assigned by a geologist based on interpretation of information provided in each report.
  • USGS = Number of responses received by the U.S. Geological Survey through their web site.
  • MGS = Number of responses received by the Maine Geological Survey through their web site.

Data in this list were collected between March 6 and March 8, 2005.

Town MMI USGS MGS
Andover II 2  
Anson IV 1  
Ashland IV 5  
Auburn III 2 3
Augusta III   3
Augusta II 7 2
Bangor III   1
Bangor II 3  
Bar Harbor II 1  
Belfast III 1  
Belgrade III 1  
Benedicta V 1  
Bethel II 1  
Biddeford III 1  
Bowdoinham II 1  
Brewer III 5  
Brewer II   1
Bridgton II 1  
Brownville III 2  
Brunswick III 7  
Brunswick II   2
Bryant Pond II 1  
Camden III 2 1
Camden II   1
Cape Elizabeth II 1  
Caribou III 5  
Columbia Falls IV 1  
Cumberland II 2  
Detroit II 1  
Dexter III 1  
Durham II 3  
Ellsworth III 1  
Fairfield III 2  
Falmouth II 2  
Farmingdale III 2  
Farmington III 5 1
Fort Fairfield III 2 1
Fort Kent IV 12 2
Fort Kent III   3
Frankfort II 2  
Freeport IV 2  
Frenchville IV   1
Frenchville III 1  
Gardiner III 5  
Gorham II 3  
Grand Isle II 2  
Hallowell IV 2  
Hallowell III   1
Hampden III 2  
Holden II 1  
Houlton II 2  
Jackman III 4  
Kents Hill III   1
Leeds II 1  
Lewiston II 3  
Lincoln III 4 1
Lisbon II 1  
Littleton III   1
Livermore Falls IV 2  
Madawaska III 9  
Madison III   1
Manchester II 1  
Mapleton IV 2  
Mariaville III   1
Mechanic Falls III   1
Millinocket IV 3 1
Millinocket III   1
Milo III   1
Naples II 2  
New Goulcester II 1  
Newry III 1  
Norridgewock III 2 2
North Anson II 1  
North Monmouth III   1
North Yarmouth III   1
North Yarmouth II 5  
Old Town II 1  
Orono III 4  
Oxford IV 2  
Passadumkeag V 1  
Patten II 1  
Peaks Island II 2  
Phillips III 1  
Pittsfield III 2  
Portland III 6  
Portland II 4 2
Presque Isle III 6  
Readfield III 4  
Rockland IV 2  
Rockport II 1  
Rumford III 2  
Saco III 3  
Saco II   1
Saint Agatha III 1  
Saint David III 2  
Saint Francis IV 4  
Scarborough II 2  
Sinclair II 1  
Skowhegan IV 1  
Smithfield III 1  
South China III   1
South Portland III 3  
Stockholm III 1 1
Stratton II   1
Strong IV 1  
Topsham II 3  
Turner III 1  
Van Buren IV 4  
Waldoboro II 1  
Wallagrass III   1
Wallagrass II 7  
Waterville III   1
Waterville II 3  
West Paris III 1  
Westbrook III 1  
Wilton IV 1  
Winterport III 1  
Winthrop III 2  
Woodland III   1
Yarmouth II 6  
Totals 239 45

News Reports

The Associated Press produced a brief news release that was picked up by several newspapers in the northeastern U.S. It reported people feeling the earthquake in Boston, Montreal, and Ottawa.

Bangor Daily News, Monday, March 7, 2005, "Quebec quake felt in northern Maine".

Portland Press Herald, Monday, March 7, 2005, "Early morning earthquake felt in northern Maine".

Seismograms

The Canadian Seismic Network's Hourly Seismogram plot for March 6, 2005, 6:00 to 7:00 (UT) shows the earthquake was felt strongly at all seismic stations across the region. The Geological Survey of Canada reports that more than a dozen small aftershocks (magnitude 0.9 to 2.1) were recorded over the next 9 hours.

March 6, 2005 Riviere-du-Loupe Earthquake hourly seismic plot from the Canadian Seismic Network.

Reference

Nuttli, Otto W., 1973: "The Mississippi Valley Earthquakes of 1811 and 1812; Intensities, Ground Motion, and Magnitudes," Bulletin of the Seismological Society of America, v. 63, No.1, p. 227-248.


Last updated on April 27, 2012