"Thai" elements, bordering the Indochina block, are of
华夏古陆n type and characterised by palaeo-tropical warm-water
沉积相. The external "Shan" part has Gondwanan cold-water facies whilst the central "Sibumasu" part is transitional between the other two.
The internal parts of Shan–Thai merged with Laurasia 265 Ma when the Nan-Uttaradit suture closed.[4]
Oceanic basins separated the other elements of Shan–Thai until the Late Triassic–Early Jurassic Late Indochina Orogeny.[5]
The collision between India and Eurasia during the Oligocene and Miocene resulted in clockwise rotation of south-west Asia, severe deformation of south-east Asia, and the extrusion of Shan–Thai and Indochina blocks. These two blocks are still crisscrossed by the faults from this collision.[6]