THE STRUCTURAL FEATURES AND ORIGIN OF THE KUQA REJUVENATION FORELAND THRUST BELT

Abstract

Kuqa rejuvenation foreland thrust belt is devided into five structural zones from north to south as follows: 1. North margin thrusting cyptowedging zone, 2. Stike anticline zone, 3. North linear anticline zone, 4. Baichen pigyback depression, 5. Qiulitag frontier zone. They composed a southward thrust wedge which is about 50 km width and more than 200 km long. There are varied structural styles in the structural zones, i. e. fault bend fold, fault propagation fold, detachment fold, hybrid fault propagationdetachment fold and duplex thrust structure. There are different geological ages of growth strata in antichne limbs of different structural zones, showing the different emplacement ages of the structural zones. The Stike anticline zone was formed since Miocene (24. 5Ma). The North linear anticline zone was since middle Miocene (16.9Ma). The Dawanqi anticline in Baichen depression was since late Pliocene (3. 9Ma),and Yaken anticline in Qiulitak frontier zone was since early Pleistocene (1.8Ma). Therefore the deformation ages were younging southward from Miocene to Quaternary. The Kuqa rejuvenation foreland thrust belt is resulted from the remote tectonic effect in continent interior by the continent to continent collision of Indian to Tibetian continent.