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应用马杏垣教授倡导的构造解析方法,对湘赣边区NNE 向走滑盆岭山链的构造发展过程及样式进行了研讨,论证了该地区前中生代EW 向古特提斯构造体系与中新生代NNE向滨太平洋构造体系之间的立交桥式横跨叠加关系和构造背景,建立了华南陆壳俯冲 会聚走滑转换造山模型,提出了新华夏式变质核杂岩构造的新概念,并对其基本特征和形成机制进行了阐述。文中强调,发育在湘赣边区的NNE 向走滑断裂是郯庐断裂带南段的主干成分,由NE30°同向走滑断裂(P) 和NW320°反向走滑断裂(R′) 交织而成的雁列菱形网结系统是该断裂在地表的基本构造样式。大多数陆壳俯冲型和会聚走滑型的花岗岩都具剪切重熔成因,雁列的半地堑盆地和新华夏式变质核杂岩体主要受走滑 伸展变形场所控制。指出自晚三叠世以来,该地区曾经历了两次不同的重大构造转换和两个性质及发展趋向相反的走滑造山过程,即印支晚期的陆壳俯冲向陆内会聚走滑转换和侏罗纪时期的会聚走滑造山;早白垩世开始的会聚走滑向离散走滑转换和白垩纪- 老第三纪的离散走滑造山。每次构造转换和构造变形对该地区的成岩成矿都起到了重要的作用。
Based on the tectonic analysis method advocated by Professor Ma Xingyuan, the tectonic development process and pattern of NNE strike-slip basin ridge in the border area of Hunan and Jiangxi Province are discussed. It is demonstrated that the EW tectonic system of the Pre-Mesozoic Era to Meso-Cenozoic NNE To the overpass superimposed relationship and tectonic setting of the overpass in the Pacific Ocean tectonic system, a new model of the crustal convergence-slip-transition of the South China crust was set up, and a new concept of the structure of the Xinhua-Xiaokang metamorphic core complex was proposed. Its basic characteristics And formation mechanism elaborated. It is emphasized that the NNE strike-slip faulting developed in the Hunan-Jiangxi border area is the main component of the southern segment of the Tanlu fault zone and is intertwined by NE30 ° strike-slip strike (P) and NW320 ° reverse strike-slip fault (R ’) Into the geese rhombic grid system is the rupture of the basic structure of the surface style. Most of the continental crust subduction and convergent strike-slip granites have the cause of shear remelting. The Yanghi semi-graben basin and the Xinhua-Xiaochen metamorphic core complex are mainly controlled by the strike-slip extensional deformation. It is pointed out that since the Late Triassic, the region experienced two major structural transformations and two strike-slip orogeny processes of opposite nature and development tendency, that is, continental subduction and slip-migration in the late Indosinian and The Jurassic period was a combination of slippery orogeny; convergence and migration from the beginning of Cretaceous to discrete slip-and-fall transition and the Cretaceous-Oligocene discrete strike-slip orogeny. Each structural transformation and tectonic deformation played an important role in diagenesis and mineralization in the area.