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扬子北缘黄陵地区古构造应力场于晚中生代经历发生了重大转变,是扬子板块与华北板块在三叠纪碰撞造山之后陆内构造变形的体现。由黄陵背斜周缘晚中生代盆地充填记录所反映出这一变革的起始时间为中侏罗世晚期。早侏罗世—中侏罗世早期,盆地内沉积了以桐竹园组为代表的河流—湖泊相岩层,由沉积碎屑成分和古水流统计所得出的物源区为北部的秦岭地区,黄陵背斜上部可能也接受了碎屑沉积;中侏罗世晚期—晚侏罗世,沉积中心发生了改变,表现为仅仅在黄陵背斜西侧的秭归盆地内有所保存,沉积环境以曲流河到辫状河流和三角洲为主,物源区则局限于黄陵背斜;早白垩世初期,周坪盆地和宜昌盆地为沉积中心,近缘冲积扇和辫状河流体系占据主体,物源区依然为黄陵地区,两盆地在黄陵背斜南缘可能相连,黄陵背斜上部的原下侏罗统被剥蚀;早白垩世晚期—晚白垩世,远安盆地逐渐发育,盆地西缘为冲积扇—辫状河流体系,中、东部则以曲流河—湖泊沉积环境为主体,并间有干旱沙漠环境。原型盆地再造结果显示,早侏罗世—中侏罗世早期盆地展布具有近东西向特点,古地貌总体呈现出北部为山脉、南部为盆地的格局;中侏罗世晚期以来,盆地呈近南北向,黄陵背斜逐渐形成山脉,盆地位于其东西两侧。两期盆地沉积特征反映了扬子北缘古构造应力场由近南北向转变为近东西向的过程。
The paleo-tectonic stress field in the Huangling area along the northern margin of the Yangtze Yangtze plateau experienced a significant shift in the experience of the Late Mesozoic. It is a manifestation of the intracontinental tectonic deformation after the collision of the Triassic Yangtze block with the North China plate. The record of the filling of Late Mesozoic basins in the peripheral margin of the Huangling anticline reflects the beginning of this change in the late Middle Jurassic. Early Jurassic-Early Middle Jurassic, river-lake facies rock represented by Tong Zhuyuan group was deposited in the basin. The provenance area derived from sedimentary detrital composition and paleocurrent flow statistics is the Qinling Mountains in the north, The Upper Huangling anticline may have also received detrital sediments. In the middle Jurassic-Late Jurassic, the sedimentary centers changed. They are only preserved in the Zigui basin on the west side of the Huangling anticline, Mainly from meandering river to braided river and delta, and the provenance area is confined to the Huangling anticline. In the early period of Early Cretaceous, the Zhouping and Yichang basins are the sedimentary centers, and the alluvial fan and braided river systems dominate , The provenance area is still the Huangling area. The two basins may be connected to the southern margin of the Huangling anticline, and the Lower Jurassic in the upper part of the Huangling anticline was eroded. From the Early Cretaceous to the Late Cretaceous, the Yuan’an Basin developed gradually , The western margin of the basin is an alluvial fan-braided river system, while the middle and eastern parts are mainly composed of meandering rivers and lakes sedimentary environment with arid desert environment. The results of prototype basin reconstruction show that the Early Jurassic-Early Jurassic basin distribution has the characteristics of near east-west distribution, the paleogeomorphology generally shows the northern part of the mountain range and the southern part of the basin pattern. Since the late Middle Jurassic, the basin was nearly North-South, Huangling anticline gradually formed mountains, the basin is located on both sides of its east and west. The sedimentary characteristics of the two phases reflect the process of the paleotextical stress field in the northern margin of the Yangtze that changed from nearly NS to EW.