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The formation of the Songpan‐Garzê Fold Belt and the initiation of the terrestrial Sichuan Basin are related to closing of the Palaeo‐Tethys during the Late Triassic Indosinian orogeny. The Songpan‐Garzê Fold Belt is composed of Triassic (T₁‐_‐T²₃) turbiditic deposits and Palaeozoic greywacke‐shale, whereas the Sichuan Basin consists of Sinian to middle Upper Triassic (T²₃) platform carbonates and Upper Triassic (T_3X to Quaternary terrestrial elastics. Three principal deformation episodes during the Late Triassic (Norian to Rhaetian) were progressively localized towards the south‐eastern margin of the fold belt. D₁ was a SW‐directed shortening event, related to continuous subduction of the Palaeo‐Tethys, and produced NW‐trending structures. Differential strain between the fold belt and the Sichuan Basin was accommodated by sinistral shearing along a NE‐trending transitional zone during D₂^. D₃ SE …