| There are lots of complex geological structures in the Middle and Upper Yangtze (carton) region. This is one good natural laboratory to study intra-continental orogeny, especially for complex folds and thrust belts. The researches to them are keys to reveal structures in South China. However, there are a little study in this important area to oil-gas exploration. Different scientific ideas are split. Therefore, this thesis tries to reveal structural geometry and kinematics by the superficial characteristics using method of remote sensing technology which is based on Geographics Information System platform and finite element analysis. This paper stresses an importance of 3S technologies in structure geology. In order to do this, this research chooses some typical structural regions and creates the Shaded Relief Model to the study of folds and fractures in those typical regions. Finally, four conclusions as follows have been made.1. There are some different structures between the east and west sides of the Xuefeng mountain after analyzing the fold-systems of typical regions in detail. In the east side of the Xuefeng mountain, EW-trending folds formed in the Caledonian movement, then being superposed in the Indosinian movement which can be subdivided into two stages: the first-stage were EW-trending folding, and the second-stage northwestward-convexed thrusting to form arc-like structures; On the other hand, deformation in the west side of the Xuefeng mountain can be also subdivided into two-stage folding and one-stage strike-slipping, which occured in the Yanshanian movement. Of which the NW-trending structure was formed in first-stage Yanshanian and a series of SN-trending structure were formed in the second-stage Yanshanian. Finally, the sinistral strike-slipping happened in the Yanshanian movement. In some areas, there are some abnormal deformation such as rhombic-shaped fold superposition being controlled by border faults.2. The processes of both fold growth and formation show convergently-developed features at the conjunction point of structures or at the region of pre-existing structures strongly influencing later structures, based on the analysis of fold styles and patterns in the eastern and southeastern Sichuan Province. Moreover, the same phenomenon can be also found in the course of fault growth.3. Some new methods in this paper are proposed to distinguish the superposed structures and combined structure, including analysis fold's axial line and joint system for classical and regional deformation in the Middle to Lower Yangzte block.4. The dynamic mechanism are discussed based on analysis of the structural geometry and kinematics. However , the collission of the Yangtze block with the Indochina block and the North China block resulted in the formation of Indosinian structures. In the later Triassic, intracontinental collission of the Yangtze block with the Cathaysian block produced the NE-SW-trending arc structures. The NE-trending structures maybe be related to the NW-directed subduction of the Izanaqi and Pacific plates under the Yangtze block. At last,the subduction of the Pacific plate to the Yangtze block changed toward NWW direction and produced the SN-trending structures.
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