a concentration in the estuary, near La Malbaie and Rivière-du-Loup. Surveys and the establishment of a seismometer network were conducted in the 1970s and allowed to circumscribe the seismically active area in an area of on along the Saint Lawrence River, this zone includes the towns of La Malbaie, Baie-Saint-Paul and La Pocatière. The seismic data indicates that an earthquake happens on average every 36 hours in the Charlevoix-Kamouraska zone. They are concentrated in the Precambrian bedrock under the Logan line and the Appalachian Mountains, at a variable depth between deep and the surface Another seismic area located in the Gulf of Saint Lawrence, in a triangle between the towns of Matane, Baie-Comeau and Sept-Îles. However, this seismic area is less active than the one uphill, as only an average of sixty earthquakes occur each year and has not had a destructive earthquake in history. An earthquake of magnitude 5.1 occurred in 1944 east of Godbout and another of the same magnitude occurred on the 16 March 1999, its epicentre was located at about south of Sept-Îles. Topography The topography of Bas-Saint-Laurent has two main elements : the plateaus of the Appalachian Mountains, called Notre Dame Mountains, and the lowlands in the fine stripe of land along the Saint Lawrence river. These are separated by an intermediate area of ridges and foothills which meld with the plateaus. The Notre Dame Mountains, are a group of small mountains with summits reaching between high. the landscape is sometimes interrupted by valleys, like the Témiscouata valley or Matapedia Valley. These two parallel valleys allow access to The Maritimes, Maine and Chaleur Bay. The littoral, spanning across is composed of riverside land of altitudes ranging from above sea level. This area has a depth of before reaching the mountains in the west of the region, but reaches in the vicinity of Rimouski, only to shrink again in the eastern limits of the region. This riverside land disappears entirely between the municipalities of Sainte-Félicité and Grosses-Roches. In the western part of the territory, this littoral plain is interrupted by inselbergs, ridges reaching that can reach 200m in height, typical of the riverside land of Bas-Saint-Laurent In the Quaternary, the region was marked by glaciation. the Wisconsin glaciation caused the crust to sink by in the vicinity of Rimouski. When the end of the glaciation started in 18,000 BP, it opened a sound in the Saint-Laurent