On 6 February 2023, two large earthquakes (moment magnitude 7.8 and 7.6) shocked a vast area of southeastern Türkiye and northern Syria, leading to heavy casualties and economic loss. To investigate the rupture process over multiple fault segments, we performed a comprehensive analysis of local seismic and geodetic data and determined supershear ruptures on the initial branch and the Pazarcık and Erkenek segments and subshear ruptures on the Amanos segment of event 1. The bilateral rupture of event 2 also presents distinct sub- and supershear velocities. The dynamic stress of the branch fault rupture triggered the Pazarcık segment initial rupture at a point 9 kilometers west of the junction of these two faults, boosting the supershear rupture of the Pazarcık segment of the main fault. The geometry and prestress level of multiple segments controlled the rupture behaviors and influenced the ground shaking intensity.

We developed a hybrid algorithm using both convolutional and recurrent neural networks (CNNs and RNNs, respectively) to pick phases from archived continuous waveforms in two steps. First, an eight‐layer CNN is trained to detect earthquake events from 30‐second‐long three‐component seismograms. The event seismograms are then sent to a two‐layer bidirectional RNN to pick P‐ and S‐arrival times. The data for training and validation and testing of the networks are obtained from the continuous waveforms of 16 stations recording the aftershock sequence of the 2008 Wenchuan earthquake. The augmented training set has 135,966 P–S‐wave arrival‐time pairs. The CNN achieved 94% and 98% hit rate for event and noise segments in the test set, respectively. The RNN picking accuracies for P and S waves are $−0.03±0.48$ (mean error $±$ standard deviation) and $0.03±0.56s$⁠, respectively.

Significance: The Songpan-Ganzi terrane lies in the central-east of the Tibetan Plateau, which was considered a stable block in some tectonic models. Its deformation mode is of crucial importance for understanding the evolutionary history and seismic hazard of the plateau. The recent Maduo earthquake occurred inside the terrane. We resolve a bilateral rupture process with distinct super- and subshear rupture modes for this event. We also find that pervasive folding structures that are aligned by shear deformation in the current Songpan-Ganzi terrane are responsible for the seismic wave anisotropy and shear strain orientation in its upper crust. Its deformation mode can be classified as distributed simple shear, which receives shear loads from side walls and produces internal earthquakes.