| This paper reviews the development of the Deep Seismic Sounding (DSS) method firstly. Based on the analyzing of the DSS's basic theory of tomography,an inversion scheme that can be described as the combination of the finite-difference inversion and ray inversion using traveltime,amplitude and gravity data is proposed.The third chapter of this paper explored the method of acquiring amplitude-ratio,and also the significance of the amplitude and gravity data for the probing of the crust and upper mantle's structure is investigated. Thus the framework of inversion adopted by this paper is formed.Several numerical experiments are carried out to detect the actual steps and limitation for the velocity and depth parameter's ray inversion in the fourth chapter,and the we find that:a. the resolution capability of the layer's velocity change along both the top and bottom boundary is very poor. Thus generally the vertical homogeneous layer model whose top velocity equal to that of its bottom boundary should be considered. During the inversion process of velocity and depth parameter,the velocity parameter should be inversed firstly and then do the depth so as to assure the stability of the final results and the reliability of the solution.Take advantage of the checker-board-test method to test the horizontal resolution of velocity and depth parameter on HQ-13 profile and the four profiles of Yunnan region. It's found that the best absolute lateral resolution of the velocity on the HQ-13 profile is about 30 kilometer,while that of the depth parameter on this profile can be smaller than 10 kilometer. Both of the velocity and depth parameter points are of 20 kilometers interval on the four profiles in Yunnan region,their lateral resolution are also detected by the checker-board-test method. It shows that the resolution of the crust interface's shape on this four profiles is very good,nevertheless that of the velocity structure is relatively poor.The crust and upper mantle's fine configuration on the HQ-13 profile is obtained by our tomography,which reveals some important structure and dynamic features of this region:The velocity structure of the crust consists of three layers,the upper crust,the middle crust and the lower crust. However it also can be divided into six lateral blocks,each of them 's velocity is always higher or lower than that of its neighboring blocks. The high or low velocity anomalies's locations are consistent with the uplift and depression respectively,and their contacting boundary always correspond the faults exposed on the ground's surface. The basement interface that is the bottom interface of the sedimentary cover undulates strongly. The characters of velocity's distribution within the mid-layer of the middle crust resemble that of the upper crust's bottom layer,and the velocity strongly disturbed. The prominent higher velocity anomalies exist below the Linbi uplift and theHu-Su uplift within this layer. The velocity difference between the two layers of the lower crust is not obvious. The depth of Moho interface is about 30-36 km,and the velocity of the upper mantle is nearly 8.06-8.29 km/s.The final structure also shows that the Fuliji fault,the Songgou basin south fault,the Hongze-Liujungou fault among with other deep faults stretch into the upper mantle. While there is no distict evidence to prove the Tanlu fault's noted deep and dynamic behavior within the lower crust or even on the upper mantle. Thus there still exists a necessary to research and check the understanding about the boundary's location and the dynamic background.Base on the velocity profile,the seismotectonic environment along this profile is studied. The reason for the moderate and large earthquake of Zhengjiang block could be attribute as such features:Because of the structure's more rigidity and the rising of the several interfaces in the crust,the energy from the deep crust of upper mantle is transported to the middle or upper crust persistently. Thus it always accumulates at some locations and this may...
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