The Deep Coupling Relationship Between Tarim Basin And Altyn

The paper is based on the on the magnetotelluric sounding(MT)data of line 4000which are accomplished by the university of Geosciences.In the lab,we used modern data processing methods to finish the work of magnetotelluric data processing and,finally got the reliable MT response.By utilizing modern 2-D algorithm of inversion and a series of inversion calculation,we achieved the 2-D electrical structure model with high reliability in the survey region.According to the result of magnetotelluric decomposition of impedance tensors,the main structure of study region showed the approximate two-dimensional structure.Based on the result of data processing,materials of geophysics and areal geologic structure,initialization of MT model,we conducted the MT inversion.What's more,we discussed the investigation depth by using constrained inversion technology,analyzed the influences of the tau to the result of inversion,depicted the electric character of underground medium and then enhanced the resolution,increased the reliability of inversion model,improved the result of inversion,finally achieved the goal of inversion.The result of the research showed:Along the study area distributed many electric gradient and distortion zones.After contrasted with the regional tectonic information,we found that the position of the electric gradient and distortion zones roughly coincides with the major fault line delineated by regional geological data.The whole profile displayed the characters of vertical stratification and block distribution in north-south strike.The research displayed the Altyn Tagh Fault is nearly a lithosphere fault with upright occurrence,and vertical 80km-extention.We found the evidence that Tarim is diving into the south.Along the north edge of the Qinghai-Tibet Plateau,it's occurring the collisions of continental lithosphere block convergence.Along the south Altyn Tagh Fault,the south Tarim block dived into the Altyn Tagh terrain slantly,finally combined with the Altyn Tagh Fault in the deep.But we can also find the subduction to the Tarim basin in the middle of Altyn Tagh thrust is very limited.