Fig. 1: Tectonic setting and fault coupling ratio on the Anninghe-Zemuhe fault (AZF) system.

A Tectonic setting of the study area. Black solid lines indicate active faults obtained from the public Data catalog of the China Seismic Experiment Site. Red and gray triangles represent the 24 newly-developed near-field GNSS stations and existing stations used for constraining the kinematic coupling model, respectively. Cyan stars indicate historical events (M > 6.5) in the past 500 years (ref. ²⁴). Blue vectors show the GNSS velocity in this region (“Data availability” section). ANHF: Anninghe fault; ZMHF: Zemuhe fault; DLSF: Daliang Shan fault; LJ-XJHF: Lijiang-Xiaojinhe fault; LMSF: Longmen Shan fault. Cyan vectors in the upper left inset show the block motions. Red star and ellipse represent show the epicenter and rupture extent of the 2022 Mw 6.6 Luding earthquake. B Coupling ratio on the AZF and DLSF. The fault changes from a completely locked state to a fully steady slip state as the coupling ratio varies from 1 to 0. Gray dots show the seismicity distribution that was projected onto the faults. AZF-1 to AZF-6 show the identified asperities on the AZF. Purple dots represent the near-fault cities. The topography data used in the figure is obtained from NOAA Data Catalog. The GNSS velocities on the new stations are available at Table S1. The seismic catalog data is available in Supplementary Data 1. The figure was drawn using the GMT5 software (“Code availability” section).