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位于辽西凌源市南部的牛营子—邓杖子地区侏罗系地质问题多年来困扰着地质学家。争论最多的构造形迹是一套平面上呈狭长矩形,以断层为界的近直立中元古界常州沟组石英岩,及局部长城系顶部地层。这套地层绵延35km,呈北北东展布。其西界为近直立的大齐子断层(新命名断层)和大部分向东倒转的陡倾下侏罗统邓杖子组;东界为近直立的朱杖子断层(新命名断层)和西倾的中侏罗统郭家店组。前人的构造解释倾向于大齐子断层为邓杖子组一侧下降的陡倾正断层,朱杖子断层为郭家店组一侧下降的陡倾逆断层。文中不同意这样的解释,并发现有证据表明上述两个断层都形成于之前尚未识别出的侏罗纪构造事件时期。将大齐子断层解释为早侏罗世晚期—中侏罗世早期形成的一条向西逆冲的断层,沿着它使长城系推覆于邓杖子组之上,然后,该逆冲断层上、下盘地层共同卷入后期褶皱变形当中。朱杖子断层原本为正断层,形成于原来未识别出的中侏罗世伸展变形阶段,并构成了郭家店半地堑边界断层。朱杖子断层沿着向东倾斜的常州沟组石英岩与串岭沟组页岩的界面发育。随着断层的发育,位于常州沟组石英岩之上的串岭沟组及长城系上部地层发生拆离沉降并被埋藏在半地堑之下。随后,发生在中侏罗世晚期或晚侏罗世早期收缩构造变形,改造了邓杖子—常州沟—郭家店组构造组合的几何形态。本期改造导致以下结果:(1)朱杖子正断层发生反转成为逆断层;(2)蓟县系沿着杨杖子—瓦房店逆冲断层向东掩覆于断层围限的长城系地层及相邻侏罗系之上。同时,邓杖子组倾角加大并向东倒转。研究表明,辽西地区的侏罗纪构造演化过程远比原先所认为的要复杂。
The geological problems of Jurassic in Niuyingzi-Dengzizi area, south of Lingyuan City, western Liaoning, have plagued geologists for many years. The most controversial tectonic trace is a set of narrow and long rectangle rectangles in the plane, the upright eclogites of the Middle Proterozoic Changzhou ditch group quartz rock in the plane of the fault, and the top of the local Great Wall series. This set of strata stretches 35km, was north and north east cloth. Its western boundary is the nearly upright Dazijiz fault (newly named fault) and most of the eastward reverse steeply declining Jurassic Dengzhangzi Formation; the east boundary is the upright Zhuzizi fault (newly named fault) and the westward dip Jurassic Guo shop group. The tectonic interpretation of the predecessors tended to be that the Dazijiz fault was a steep-leaning normal fault that declined on one side of the Dengzhangzi Formation, and the Zhuzizi fault was a steep-reverse thrust that fell on one side of the Guojiadian Formation. The text disagrees with this explanation and finds evidence that both faults were formed during a previously unrecognized Jurassic tectonic event. The interpretation of the Dazijiz fault is a western thrust fault formed in the early Jurassic to early Middle Jurassic along which the Great Wall Series was thrust over the Dengzhangzi Formation and then the thrust fault , Under the formation of the common fold into the fold during the deformation. The Zhuzhangzi fault was originally a normal fault formed in the previously unrecognized Middle Jurassic extensional deformation stage and formed the Guojiadian semi-graben boundary fault. The Zhuzhangzi fault developed along the east-leaning interface between the Changzhou Ditch Group quartzite and the Shalingling Shale. With the development of faults, the Chuanlinggou Formation and the upper Great Wall series strata above the Changzhou Goushi Quartzite have been detached and subsided and buried beneath the semi-graben. Subsequently, the shrinkage tectonic deformation took place in the late Middle Jurassic or early Jurassic, and the geometry of the combination of Dengzhangzi-Changzhougou-Guojiadian Formation was changed. The reconstruction of the current period led to the following results: (1) the Zhizhizi normal fault reversed to become an inverse fault; (2) the Jixian fault covered the Changcheng system stratigraphy along the fault and east along the Yangzhangzi-Wafangdian thrust fault Adjacent to the Jurassic. At the same time, Deng Zichang group increased its inclination and turned eastward. Studies show that the Jurassic tectonic evolution in the western Liaoning is much more complicated than previously thought.