| The continental dynamics and continental geology is one of the advanced ranks of geoscience research , the continental orogenic belt is the key issues of continental dynamics .To determinate the framework and evolution of orogenic belt will be an important basis for continental dynamics study .TongHuaShan-YuShuGou area is one of the typical western mountainous district of high and cold, with the bareness of the surface and bad environment. it is difficult to do the field geological mapping there . however geological information is fully recorded in the remote sensing image, which made it possible for the choosing of this area as a dissection point to extract complex structural information of orogenic belt in west china. Taking fully advantage of multi-band image richly bearing concealed geological information in combination with remote sensing analysis and structure analysis, to anatomy the supracrustal composition and structure of orogenic belt with the regional linear structures and their partitioned block and schistous geological masses as the macro-frame(in corresponding to structure units and structure segments) and with the rock masses, structure-rock assemblages, line-featured and belt-featured structures as well as penetrative and non-penetrative foliation (primary stratum and trans position layering) and folds as the texture and structure elements .The methods of how to distinguish granulite > ductile-shear zone, imposed fold, different deformed belts -. different rock mass on the remote sensing images were obtained, based on a comprehensive remote-structure analysis, a new acknowledge on the characteristics of regional structure in TongHuaShan-YuShuGou area was acquired .It was suggested that TongHuaShan-YuShuGou area underwent multi-phase structure movement, multi-phase, multi-orientation> multi-level deformed structure superimposed each other accompanied with complex deformation. The style of deformation in different rock mass and tectonic units is varied . According to the distinction of stratigraphic assemblage ,rock type .tectonic block type and the characteristics of deformation ,the whole district can be subdivided into three structure belt .namely southern and northern metamorphic fold stratigraphic system and central tectonic mixed system and multi-stage intruded magmatites. The north belt is mainly composed of Silurian marble , chlorite-quarts schist ,biotite-quarts schist. Lithologically different rock sheets intertexturally superimposed with faults and folds of various styles .while, the southern belt is chiefly of Devonian tuff ,tuffaceous schist ,marble relatively stable in strata and manifested by regional asymmetric fold easi-westward in axis, with well developed superimposed overthrust south-northward which controlled the whole structural framework in this area . the central tectonic belt is complex in strata , reflected by matching up of rock blocks with different ages x lithology and scales . especially interesting is the serpentinous peridotite in this belt occurred as lense blocks of various sizes, and superimposed with other geological masses with faults, and in combine to constitute the mixture .system in the belt. five tectonic stage can bediscerned in this area: (1 )south-north ward overthrust; (2)sinistral strike-slip (3)dextral strike-slip (4)south-north ward overthrust (5) northeast, northwest late stage fault...
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