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笔者总结了近年来的研究成果认为,中国东部的郯庐断裂带自海西期以来经历了两个主要发展阶段:第一阶段是广义的郯庐断裂带发展阶段,晚三叠世—早侏罗世由于扬子地块与华北地块的碰撞,成为两地块的对接边界,具有逆冲推覆的性质,属广义的特提斯构造域。第二发展阶段从早白垩世以来,发展成为一条平移断裂带,属于狭义的环太平洋构造域的平移系统。岩相古地理资料显示了扬子地块与华北地块的对接始于晚二叠世早期;印支期的郯庐断裂带是一条由NE、NNE向展布的缓‘S’型的地块拼贴边界,在现今的郯庐断裂带上表现为残留的由北北西向南南东的斜向逆冲推覆的性质,中下构造层次表现为韧性逆冲推覆变形,上部构造层即前陆褶皱冲断带内的变形;应力场分析资料显示:早三叠世晚期开始地表浅部就有近南北向的挤压作用,左行走滑平移作用开始发育;早白垩世晚期开始转入引张伸展阶段,与中国东部的伸展作用一致;新近纪又转为近东西向挤压,发育逆冲兼右行走滑作用。
The author summarizes the research results in recent years that the Tanlu fault zone in eastern China has undergone two major stages of development since the Hercynian period: the first stage is the development stage of the Tan-Lu fault belt broadly defined, the Late Triassic-Early Jurassic Due to the collision between the Yangtze block and the North China block, the Loess became the docking boundary between the two blocks and had the characteristics of thrust nappe, belonging to the generalized Tethyan tectonic domain. The second stage of development has developed into a translational fault zone since the Early Cretaceous and belongs to the translational system of the Pacific Rim tectonic domain in a narrow sense. The lithofacies palaeogeographic data show that the connection between the Yangtze block and the North China block started in the early Late Permian. The Indo-China Tan-Lu fault zone is a slow “S” -type block spread by NE and NNE The collage boundary is characterized by the residual thrust nappe thrust from northwest to southwest on the present Tan-Lu fault zone. The middle-lower tectonic level is characterized by ductile thrust nappe deformation. The upper tectonic level Deformation in the foreland fold-thrust belt. The analysis of stress field shows that there is near-north-south crustal extrusion in the shallow part of the Early Triassic and the left-lateral slip-migration begins to develop. In the late Early Cretaceous, Extensional stretching stage, consistent with the extension of eastern China; Neogene and into the nearly east-west extrusion, the development of thrust and right-sided slippage.