Numerical modeling on the tendency of collision between the Pamir—west Kunlun tectonic system and the west Tienshan one

Category Tectonic & Seismotectonic
Group GSI.IR
Location International Geological Congress,oslo 2008
Author Qiu, Zhuli; Li, Haibing; Si, Jialiang; Pan, Jiawei
Holding Date 03 September 2008

Since the collision between the Indian plate and the Eurasian plate about 55Ma ago, the intensive intercontinental convergence has formed the huge deformation domain between the Qinghai-Tibet Plateau and middle Asia. As an instance, The Tienshan deformation domain is the remote effect of this collision, whose western part has collided into the Pamir-west Kunlun tectonic zone, northwest of the Qinghai-Tibet Plateau, and has formed a sophisticated geologic body and unique geomorphic features. Studies of individual geologic processes, such as shortening or uplifting rate, of the southwest Tienshan, the Tarim Basian, and the Pamir-West Kunlun mountains are drawing more and more attentions from all over the world. Unfortunately, most of the efforts are within several sections and are lack of prediction of future geologic and tectonic processes. Furthermore, the interaction among these geologic bodies is seldom reported. So, an issue is put forward to us that numerical modeling of discrete parts of southwest Tienshan, the Tarim Basin, the Pamir-west Kunlun geologies, influences of the geologies on each other, and the future evolution of this zone—the collision between the west Tienshan system and the Pamir—west Kunlun system—should be discussed in detail. To do so, we are applying various theories and new technologies. The primary steps follow bellow: first, determining foreland thrusting of southwest Tienshan and west Kunlun over the Tarim basin by detailed researches of tectonic deformations, accretionary strata, and dating of young geologic bodies; then deducing directions and values of several paleotectonic stress fields of different time since Cenozoic with the help of structural feature analyses and Kaiser effect theory; and at last, finding out the rule of changes of paleotectonic stress fields and, combined with finite element theory (a numerical modeling method) and GIS software, applying it to the prediction of future stress fields, thus relief evolution, deformation mode and quantities, and collision tendency of the discussed zone.