The Tectonic Deformation Analysis Of Benbatu Formation In Eugerwusu Area, Alxa Right Banner, Inner Mongolia

The study area is located in china-mongolia border region, south marginal active belt of northwest of north China plate.It has experienced a complex geological evolution process. Under the influence of different tectonic unit and structural evolution stages,geotectonic position is very important, but because of the natural conditions, the research level is low. The purpose of the study is that Through the study of the analysis of 1:50000 geological map of Engel Wu Su region, combined with tectonics deformation geology survey to give a detailed set of Fold feature. Establish a relatively complete framework and make A detailed set in the fold. Through detailed field geological survey, the new discovery are:There are three periods of fold in the study area. Hub,s approach is SE, SW, EW and NS.The first fold is a Homoclinal overturned fold and is Strata fold of the original bedding。Due to the effect of superposition of the late folds, the early tectonic structural development is more dispersed,which reflects Rock initial stage is formed by bedding shearing action.The second fold of benbatu formation is the largest one, and has nearly east-west axis trace. The collision to extrusion pressure of Engel Wu Su fault zone formed in the benbatu formation. Due to the late fold superposition reconstruction,The middle fold of wave bending axial trace.The last fold of principal stress orientation changes to the east-west squeezing effect, forming rolling fold. The formation of the late fold structure exists the possibility of two aspects. On the one hand, after the collision of Engel Wu Su fault zone, principal stress change. Fold the formation of the third stage of near NS to wide. On the other hand, Mainland China intraplate degeneration characteristics to form a series of NNE and NE to buckling folds in Yanshanian epoch, and the intensity of tectonic movement characteristics of strong east west general weakness. In Yanshanian epoch fold axial can change with time,and Fold axis rotate counterclockwise. Benbatu formation phase 3 fold formation may be associated with it.