A NUMERICAL SIMULATING RESEARCH ON NEOTECTONICS IN THE LOP NUR BASIN

Based on analysis of previous researches on neotectonic in Lop Nur Basin, two types of numerical simulation models have been built in this paper: ~N-S trending compression in first stage and NE-SW striking compression in the later stage. Combining with the previous studies, our numerical simulation shows the two main episodes of tectonic evolution occurred in the Lop Nur Basin since Late Cenozoic: (1) the ~N-S trending compression, the extension and rifting from late Oligocene to Early Pleistocene, and (2) the NE-SW striking compression and the shearing deformation since Early Pleistocene. Furthermore, the research shows the stress condition of the geological units is controlled both by lithology and faults; moreover, the low stress appears inside of the basin, and extensional direction is perpendicular to maximum principle compressive stress. The two main faults to the south of the basin are dominated by high shearing stress, whereas the minimal shearing stress distributes both in the basin and to its east. Furthermore, obviously controlled by faults, the displacement decreases from southwest to northeast, indicating the pore fluid migrates from southwest to northeast. This study provides some structural evidences for the research on sylvite forming and oil storage and transformation.