The Deformation Characteristics And Geological Significance Of Hechi-yizhou Fracture Zone In Guangxi

The paper on the basis of field geological investigation and the previous data,researching the deformation characteristics?tectonic style ?structural characteristics of fracture zone between the north and the south on both sides of the research of the Hechi-Yizhou fracture zone,Mainly in the following:(1)Fracture zone overall it nearly east-west width slow exhibitions throughout north of GuiZhong depression,by article 2 nearly east-west main faults and hostage to nearly east-west double fold(syncline).The double fold(syncline)as the fracture bend fold,near the breakup rock steepening,away from the slow,give priority to with interlayer sliding.(2)Fracture zone is divided into western and eastern,western to Hechi section and Yishan section,eastern to Liucheng section and YingShan section,eastern deformation intensity is better than the western.In the section for the western is half positively flower structure,Eastern positively flower structure,fracture zone is a positive flower structure as a whole.(3)Fracture zone with compressive tectonic style,extensive tectonic style and strike-slip tectonic style,compressive tectonic style is mainly characterized by fracture fold and fracture fold,extensive tectonic style valley rift and strike-slip tectonic style main show is positive flower structure,fracture zone as a whole is given priority to with positive flower structure.(4)Fracture zone north side develop a series of high NNE Angle fault,its southern end in Hechi-Yizhou fracture zone,the east convex right traction point;Fracture zone south side develop a series of high NNE Angle fault and fold,its northern end in Hechi-Yizhou fracture zone,the west convex right traction point.The Siding zone was found nearly NS-trending basal fracture,right-lateral strike-slip properties,also show Guangxi North uplift right-lateral strike-slip properties;Formed by the north-south trunk fracture clamping "gourd shape" compound synclinal trail toward the east,illustrates the fracture zone show dextral shear,and traction on either side of the fracture zone in the south,north tectonic showed consistent direction of kinematics.(5)Fracture zone in the tectonic evolution process is divided into four stages,stage Caledonian orogeny formed fracture zone,Hercynian stretch fracture activity,Indosinian epoch fault happened into reverse-strike-slip fracture,fracture paragraphs start together,the fracture occur right-lateral strike-slip,until the end of indosinian movement,the structure of the fracture pattern basic finalize the design;Yanshan epoch superimposed transformation of fracture with a faint,but the impact is not big.The above understanding to guangxi structural framework and south China plate multiphase tectonic activity is of important geological significance.