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自元古代以来，北大巴山经历了构造伸展（∈－Ｄ２）、构造反转（Ｔ２）和构造冲断作用（Ｔ２－Ｊ１）。伸展构造主要由极性相同、北倾的大型犁式正断层构成，它控制了早古生代地层的强烈差异沉积。其成因可能受控于扬子板块北缘早古生代幔源裂谷作用所引起的大陆边缘岩石圈拉伸、减簿的动力学机制。之后，因华北和扬子两板块的对接和碰撞，扬子板块北缘发生内硅铝层Ａ型俯冲。使北大巴山构造作用由早期的伸展向大规模的冲断转变，形成中三叠世区域性构造反转作用。经构造反转后，北大巴山构造变形以强烈的深层次韧性滑脱和浅层次脆性冲断为特征。深层滑脱由发育在１０－３５ｋｍ的韧性台阶状逆断层冲断叠置而成、浅层滑脱则主要由脆性台阶状断层构成的盖层冲断岩席，双重推覆体和冲起构造等构成。由此北大巴山区地层缩短率平均至少达３５．５％－４４．２％，并造成绿片岩相的活化盖层
Since the Yuan dynasty, the northern Dabashan experienced tectonic extension (∈-D2), structural inversion (T2) and tectonic thrusting (T2-J1). The extensional structure is mainly composed of a large plow normal fault of the same polarity and a north dip, which controls the strongly differentiated sediments of the Early Paleozoic strata. Its origin may be controlled by the northern margin of the Yangtze plate caused by the Paleozoic mantle rifting in the northern margin of the continental margin of the lithosphere stretching, reducing the dynamic mechanism of the book. Later, due to the docking and collision between the two plates of North China and Yangtze, an A-type subduction occurred within the northern margin of the Yangtze plate. So that the North Dabashan tectonic role from the early extension to a large-scale thrust change, the formation of the Middle Triassic regional structure reversal effect. After structural inversion, North Dabashan tectonic deformation is characterized by strong deep-level ductile slip and shallow-level brittle thrust. Deep detachments are superimposed by ductile stepped reverse thrust faults developed at 10-35km. The shallow detachment is mainly composed of caprock thrust beds, double nappe structures and rushed structures formed by brittle stepped faults . As a result, the strata of North Dabashan area shortened an average of at least 35.5% -44.2% and resulted in the activation of the greenschist facies