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The topographic descent from the eastern margin of the Tibetan Plateau to the Sichuan Basin passes through the Longmen Shan Thrust—Nappe Belt, which is sub-divided by six NW-dipping, major listric thrusts, with accompanying duplexes and imbricate fans, into five large-scale nappes. Each nappe has its own stratigraphic and deformational features. In the inner Longmen Shan (Longmen Mountains), allochthonous nappe units have incorporated both Mesoproterozoic basement and Sinian (Neoproterozoic) to Triassic cover sequences as ‘thick-skinned’ horses; whereas in the frontal Longmen Shan, Sinian—Cretaceous cover sediments have been stripped from the basement as ‘thin-skinned’ fold and thrust sheets, including the extensively distributed klippen structures. Pre-thrusting extension during Devonian to middle late Triassic times resulted in syn-depositional normal faults. Structural inversion of these …