Source parameter studies on the 8 January 2017 Mw 6.1 Resolute, Nunavut, Canada, Earthquake

• Published in: Seismological Research Letters
• Main Authors: Motazedian, D. (Dariush), Ma, S. (Shutian)
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2018
• Subjects: Arctic; Nunavut; Canada
• Online Access: https://ir.library.carleton.ca/pub/18325; https://doi.org/10.1785/0220170260

On 8 January 2017, a strong earthquake with Mw 6.1 occurred 8° north of the Arctic Circle and 90 km southeast of Resolute, Nunavut, Canada. Because the epicenter was in a very remote region, the seismic station coverage was not good. As such, the errors in the source parameters determined using conventional procedures were not small. In this article, some results obtained on the source parameters by processing waveform records and modeling procedures are introduced. The teleseismic depth phase sP was used to determine the focal depths of the mainshock and the two principal aftershocks, because the nearest seismic station was at a distance of ∼90 km. The selected mantle Rayleigh-wave records surrounding the epicenter were used to invert for the moment tensor of the mainshock, and the nodal plane corresponding to the rupture plane was selected by analyzing the arrival-time differences between the Sg and Pg or Sn and Pn phases at the three close stations. Based on the focal depth values, it was found that the mainshock and its two principal aftershocks occurred within the lower crust. The fault plane was inferred to strike southeast and dip to the southwest, from the relocated hypocenters of the mainshock and the two principal aftershocks. A procedure using the calculated sP-P time duration to quickly determine focal depth was established. An average crustal model surrounding the epicenter was retrieved using Rayleigh-wave dispersion data.