Dr. Ali Misaghi, Dr. Mohammd Raeesi,
Volume 19, Issue 4 (12-2024)
In this comprehensive study, we investigate the spatial distribution of landslides, strong motion data, and seismic intensity patterns associated with the June 20, 1990, earthquake, which registered a moment magnitude (Mw) of 7.4. Our primary objective is to elucidate the rupture characteristics of this significant seismic event. A focal point of our analysis is the southeastern segment of the coseismic rupture zone. By integrating geological field observations with seismological data, we aim to determine the extent and nature of the rupture along this segment. Our findings indicate that the southeastern segment experienced only a partial rupture during the 1990 earthquake. This partial rupture is evidenced by the distribution and density of landslides, variations in ground motion recordings, and the observed intensity patterns. The incomplete rupture of this segment suggests that it retains a considerable amount of accumulated strain energy, which was not fully released during the 1990 event. Consequently, this segment remains a potential source for future seismic activity. The implications of these findings are significant for seismic hazard assessment and risk mitigation in the region. Understanding the rupture dynamics and the potential for future seismic events is crucial for developing effective preparedness and response strategies. Our study underscores the importance of continuous monitoring and detailed geological and seismological investigations to better anticipate and mitigate the impacts of future earthquakes.
