The Structural Characteristics And Evolution Of Jiaolai Basin

JiaoLai basin is a continental basin of Mesozoic era between JiaoBei uplift and Jiaonan orogenic belt which consists of three major fault zones, its western boundary is YiShu fault zone, southern boundary is WuRong fault zone, middle part is MuJi fault zone. The secondary fault has obvious control action to the two levels of tectonic elements growth and theevolution in basin. The faultsare all the normal faults and west Near East direction,controled by first-level of faults, activity in multi-stages, active stages is Wang stages.There exists three SN trending secondary structural units,i.e.Laiyang depression,DaYetou convex, Gaomi depression. According to its sedimentary formation and active characteristics of major fault zones JiaoLai basin is a compression contorted basin,its formation and evolution has close relationship with the subduction of the Pacific plate to Eurasian plate in Mesozoic era. The Jiaolai basin was dismemberment to inequality size, the dissimilar shape and form fault block by the different scale and heterogeneity faults which were fomed in different time, and have complex and ordery movement by pressed, extended and slippery, The movement form mainly has several kind of forms,the pressing, the horizontal extends, the vertical difference fluctuation, the fault block raises slanting revolves, relatively slippery movement and so on The evolution of JiaoLai basin can be divided into five active stages,namely basement folding stage,spreading and subsiding stage,volcanic activity stage,activity period and consuming stage.