Rupture kinematics of the three Gazli major earthquakes from vertical and horizontal displacements data

Abstract An inversion of horizontal and vertical displacement data in the Gazli region shows that the Gazli earthquakes of April and May 1976 and March 1984 occurred on variously orientated fault planes (dipping to the ESE, N, and ESE, respectively). The kinematics of the 1984 seismic rupture exhibits a pure thrust slip motion of 2.5 m. Common data for distinct events during the 1976 rupture sequence are not optimal to solve the rupture characteristics. However, the complexity of the faulting is highlighted by (1) well-resolved different dips for the two shocks. (2) strike-slip components of motions on fault planes (with thrust-motion components close to the value of the 1984 event), and (3) discrepancy between geodetic and seismic fault models for the April 1976 earthquake. The results express the complex mechanics that drive compound intraplate earthquakes.

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