western quebec and southern ontario - Department of Geology

Quebec Seismic Zone (WQSZ), the Charlevoix Seismic Zone (CSZ), the Lower St.Lawrence Seismic Zone (LSZ) and the Southern Ontario Seismic Zone (SOSZ) (Figure2.3) (Adams and Basham, 1989), likely associated with the reactivation of lateProterozoic to Paleozoic and Mesozoic rift systems along the St. Lawrence and OttawaRivers (Thomas, 2006). Figure 2.3 shows the distribution of recent seismic events ineastern Canada. As can be seen from this figure, earthquakes are generally concentratedin a few seismically active zones including the NE-striking bands of earthquakes alongthe St. Lawrence valley and the Appalachian Mountains, and the NW-striking band ofseismicity consistent with the locations of kimberlite intrusions and other igneous activityalong the inferred continental track of the Great Meteor hotspot (Heaman andKjaarsgaard, 2000). There is also a seismically active area around the west end of LakeOntario and south of Lake Erie. Adams and Basham (1989) argued that most of theevents in southeastern Canada were associated with the reactivation of a Late Proterozoicto Paleozoic and Mesozoic rift system along the St. Lawrence and Ottawa Rivers(Thomas, 2006). Adams and Basham (1989) grouped the seismicity into four seismiczones (Figure 2.3):• The Western Quebec Seismic Zone (WQSZ) (northeast of Ottawa River)• The Lower St.Lawrence Seismic zone (LSZ)• The Charlevoix Seismic zone (CSZ)• Southern Ontario Seismic Zone (SOSZ)11