The 11/25/88, M=6 Saguenay Earthquake near Chicoutimi, Quebec: Evidence for anisotropic wave propagation in northeastern North America

摘要: On November 25, 1988, a magnitude 6 earthquake occurred in the province of Quebec, Canada. This triggered nine digital strong motion instruments New York and Maine at epicentral distances 200 to 820 km which were installed as part an effort by National Center for Earthquake Engineering Research (NCEER) study ground motions wave propagation eastern North America. We calculate Q(f) discrete frequencies from 0.6 26 Hz, assuming that geometrical spreading causes l/r0.5 decay spectral amplitudes. Of stations, four are Adirondack Mountains three Maine. If we these two clusters stations separately, obtain higher values stations. The Quebec-Adirondack path is along strike predominant structural trends northeastern America, Grenville Province crust, while Quebec-Maine high angle grain crosses boundary between Appalachian provinces. thus have instrumental data support earlier observations based on contours intensity historic earthquakes: Seismic America more efficient predominantly NE-SW striking geological trends. address possible biases due site effects.