Quick output parameters related to the 2 December 2023 M_W7.6 Mindanao, Philippines earthquake

At 22:37 on December 2, 2023 (Beijing time), a M7.6 earthquake occurred in the eastern waters of Mindanao, Philippines. The Institute of Geophysics, China Earthquake Administration initiated the response mechanism after this earthquake and organized geophysics researchers to estimate the source parameters, focal mechanism, rupture process and earthquake radiation energy of this earthquake. Based on the source model, the Shakemap and the coseismic deformation field simulation are carried out. Product results demonstrate that this earthquake occurred on the subduction zone slab where the Philippine Sea Plate collided with the Eurasian Plate/Sunda Block. This earthquake is of dominant thrusting mechanism. The energy was concentrated and released in the first 40 seconds. The maximum slip of the fault rupture is up to 7 m. The efficiency of the earthquake source in radiating seismic energy is low and the slowness coefficient is slightly lower than the average level of the global same moment magnitude earthquake, and the feeling of the earthquake is relatively weak. The earthquake intensity in the extreme seismic area possibly reaches more than Ⅸ, and the approximate disaster range is up to 27000 km². This earthquake caused apparent coseismic displacement with the maximum displacements reaching 0.6 m and 1.2 m in the horizontal and vertical directions respectively. Comprehensive analysis shows that this earthquake can’t produce a large-scale tsunami.