Role of stress triggering in earthquake migration on the North Anatolian fault
Ten M???6.7 earthquakes ruptured 1,000 km of the North Anatolian fault (Turkey) during 1939-92, providing an unsurpassed opportunity to study how one large shock sets up the next. Calculations of the change in Coulomb failure stress reveal that 9 out of 10 ruptures were brought closer to failure by the preceding shocks, typically by 5 bars, equivalent to 20 years of secular stressing. We translate the calculated stress changes into earthquake probabilities using an earthquake-nucleation constitutive relation, which includes both permanent and transient stress effects. For the typical 10-year period between triggering and subsequent rupturing shocks in the Anatolia sequence, the stress changes yield an average three-fold gain in the ensuing earthquake probability. Stress is now calculated to be high at several isolated sites along the fault. During the next 30 years, we estimate a 15% probability of a M???6.7 earthquake east of the major eastern center of Erzincan, and a 12% probability for a large event south of the major western port city of Izmit. Such stress-based probability calculations may thus be useful to assess and update earthquake hazards elsewhere. ?? 1997 Elsevier Science Ltd.
Citation Information
Publication Year | 1996 |
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Title | Role of stress triggering in earthquake migration on the North Anatolian fault |
DOI | 10.1016/S0079-1946(97)00039-6 |
Authors | R. S. Stein, J.H. Dieterich, A.A. Barka |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Physics and Chemistry of the Earth |
Index ID | 70018540 |
Record Source | USGS Publications Warehouse |