[SSS10-P05] The Study of Nowadays 3D Crustal Movement in Fenwei Graban System
Keywords: Fenwei gruban, Crustal movement, Block model
The present crustal vertical velocity field image relative to ITRF2008 is obtained by the precise leveling data from 1970 to 2014 and the vertical velocity of the continuous GPS stations within this region were as a priori constraints. The image reveal that the Ordos block shows overall uplift rates of 3mm/a and Liupanshan-longxi block shows uplift rates of 4-5mm/a. Weihe basin shows subsidence rates of 3-5mm/a relatively Ordos block, while subsidence rates of 2-4mm/a relatively the North Qinling Mountains. Relatively Ordos block and Zhongtiaoshan , the Linfen - Yuncheng Basin demonstrate a subsidence rates of 4-5mm/a. Using the block model and dislocation model, the slip rates and locking depths of the major faults in the Fenwei rift zone were obtained. Our research results provide an important basis for the study on the interaction mechanism between the Qinhai-Tibet block and north China block and long-term risk prediction of regional large earthquakes.
In our study, we suggest a flow model by combing the results of FEA, analysis of Crustal movement profiles with lithospheric mantle deformation from the SKS fast-wave direction. The soft materials beneath the upper crust of Tibet plateau flow towards NE direction, because of the obstruction from the deep root of the Ordos block, the west part flow to Yinchuan along the edge channel, and the south part flow towards the North China across channel under the Fenwei graben.