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Summary The Daliang Shan is a tectonic unit that connects the active southeastern Tibetan Plateau with the stable South China block. As a newly generated (formed later than the Xianshuihe–Xiaojiang active fault system) seismotectonic zone induced by the Tibetan tectonics, the detailed constraints of the crustal deformation are central to the understanding of the kinematics and dynamics of the Tibetan expansion. This paper establishes and analyzes a high–spatial resolution global positioning system (GPS) velocity field from a dense GPS network in this region. Our modeling results indicate that, in contrast to the equivalent sinistral strike–slip rate of approximately 5 mm/yr on the Anninghe–Zemuhe and Daliangshan faults, their inferred interseismic locking depth varies within a large range. The southern segment of the Anninghe Fault and the middle segment of the Daliangshan Fault have deep locking depths of ∼13 km, indicating that the seismic risk is high in these areas. In addition, the detectable counterclockwise rotation rate of 0.35 ± 0.12°/Myr of the Mabian block makes a significant contribution of ∼50 per cent to the strike–slip motion on its boundary faults. This counterclockwise rotation may be induced by a left-lateral shear gradient with SE-ward motion relative to the South China-fixed reference frame, indicating the significance of a simple-shear pattern in exploring the kinematics of the encroachment of the Tibetan tectonics upon a stable block (craton).

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