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劈理构造是一定应力场中形成的具有透入性的面状构造,一般代表变形过程中的最大压扁面.通过了解某一区域的劈理特征和发育序次,能对该区域的构造变形序次和大地构造演化研究有一定的指示意义.在准噶尔盆地西北缘扎伊尔山石炭纪地层中发育多组透入性的劈理构造,通过实地对研究区内劈理系统性地观察,理出了3类劈理:(1)早期与蛇绿混杂岩构造就位相关的劈理;(2)晚期顺达尔布特断裂和哈图断裂发育的断裂劈理以及(3)方位十分稳定,与层理发生不同程度置换,构成不同大小的夹角,代表近南北向区域性挤压运动的近EW向劈理.早期劈理产生于晚石炭世早晚之交,与研究区内蛇绿混杂岩系在晚石炭世陆块斜向汇拢洋盆汇聚闭合、蛇绿混杂岩陆续构造就位于上覆相对较新的地层系统有关;大型断裂劈理与区域内二叠-三叠纪大规模的北东-南西向断裂左旋走滑有关;东西向劈理切过305±15Ma的花岗斑岩脉,而未影响到不整合于石炭系地层之上的中生代地层(最老为晚三叠世),结合区域构造背景确定其形成时限为二叠纪末-早中三叠世,与第2类劈理近于准同时,可能与西伯利亚板块向南推挤导致的近南北向陆内挤压有关.
The cleavage structure is an intrusive planar structure formed in a certain stress field and generally represents the largest crushed plane in the deformation process. By understanding the cleavage characteristics and the development order of a certain region, the structure of the region Deformation order and tectonic evolution research has certain significance.Multiple groups of penetrating cleavage structures are developed in the Carboniferous strata of Zaire Mountain in the northwestern margin of the Junggar Basin, and systematically observe the cleavage in the study area , Three types of cleavages were identified: (1) cleavage in situ associated with ophiolitic mélange structures in the early stages; (2) cleavage of the Late Sundalbt fault and Hatu fault development; and (3) Stable and stratified with different degrees of replacement, constitute the angle of different sizes, representing near-north-south regional squeeze movement near EW cleavage Early cleavage produced in the late Carboniferous at the turn of the morning and evening, and the study area snake The green melanges are converged and converged in the oblique oceanic basins of Late Carboniferous. The ophiolite melanges are located in the overlying relatively new stratigraphic system. Large-scale fault cleavage is related to the Permian-Triassic Large-scale North-Southwest fault has left-lateral strike-slip faults The cleats of 305 ± 15Ma granite porphyry cut by east-west cleavage without affecting the Mesozoic strata (the oldest being Late Triassic) unconformable to the Carboniferous strata, and their formation was confirmed by the regional tectonic setting The time limit is from the end of Permian to the Early Triassic, which is close to that of the second type of cleavage. It may be related to the near-north-south intracontinental extrusion caused by the thrusting of the Siberian plate to the south.