Applying the theory of collision orogenic tectonic facies, the authors investigated Triassic sedimentary characteristics and the tectonic environment in the Tianshuihai area, and also researched the structural style and its evolution in the foreland fold and thrust belt (caused by the collision between the Qiangtang terrane and the Tarim plate in the late Triassic). By analyzing the chemical components and sedimentary characteristics of the strata, the authors conclude that the sediment is a set of typical deep-water to semi-deep-water flysch formed in a passive continental margin. In the light of deformational characteristics, the foreland fold and thrust belt can be divided into five zones from NE to SW, i.e.: the trailing edge zone, root zone, central zone, front zone and edge zone. From NE to SW, the deformation becomes weaker progressively. The thrusting trend has high-angle associations. The characteristics of the fold style is SW-inverted fold to board fold along the NE-SW direction. Based on the above, the authors put forward an evolutionary model of the foreland fold and thrust belt in the Tianshuihai area: Before the end of Triassic, the area was a passive continental margin in the north of Qiangtang block. At the end of late Triassic, this block collided with the south margin of Tarim plate. From the end of Triassic to early Jurassic, the sedimentation in the passive continental margin ceased and this area entered an evolution stage of thrusting, folding, uplifting to form a foreland basin because of the collision between the block and the late Paleozoic-early Mesozic island arc on the south of the Tarim plate.
|Number of pages
|Acta Geologica Sinica (English edition)
|Published - 2000
- Foreland fold and thrust belt
- Imbricate fan
- Passive continental margin
- Western Kunlun Mountains