Charlevoix Seismic Zone Charlevoix Seismic Zone The Charlevoix Seismic Zone is a seismically active area in the Charlevoix region of northeastern Quebec, Canada. It is also known as the Charlevoix-Kamouraska Seismic Zone because earthquakes occur in Kamouraska County where the land expression of the seismic zone is separated by the Saint Lawrence River. Much seismic activity takes place under the river. With over 200 small earthquakes occurring each year, the Charlevoix Seismic Zone is one of the most active seismic zones in Canada. Since 1663, five damaging earthquakes have occurred in the area, including a magnitude 7.3-7.9 event in 1663, a magnitude 7.0
Seismic tomography better understand core, mantle, and plate tectonic processes. Tomography is solved as an inverse problem. Seismic travel time data are compared to an initial Earth model and the model is modified until the best possible fit between the model predictions and observed data is found. Seismic waves would travel in straight lines if Earth was of uniform composition, but the compositional layering, tectonic structure, and thermal variations reflect and refract seismic waves. The location and magnitude of these variations can be calculated by the inversion process, although solutions to tomographic inversions are non-unique. Seismic tomography is similar to medical x-ray