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位于华北克拉通东部的辽东半岛记录了大量的晚中生代的伸展构造,其中包括:(1)具有氧化条件下沉积的陆相碎屑岩和溢流喷出的火山岩作为充填物质的半地堑盆地;(2)低角度拆离断层;(3)同构造花岗岩;(4)变质核杂岩.上述伸展构造在区域尺度上均具有NW-SE向的伸展方向.拆离断层具有NW-SE向的矿物拉伸线理和上部指向NW的剪切变形;同构造花岗岩的矿物拉伸线理也为NW-SE向,但表现为上部指向NW或SE的剪切变形.同位素年代学的测量结果指示了变形的时间在130~120Ma.这些伸展活动导致了同构造花岗岩和核部杂岩的快速隆升和折返.根据岩浆岩发育特征和辽东半岛伸展构造、岩浆作用的时空关系判断,华北克拉通破坏可分为侏罗纪地壳弱伸展和白垩纪强地壳伸展两个阶段.
The Liaodong Peninsula, located in the eastern part of North China Craton, recorded a large number of late Mesozoic extensional structures, including: (1) semi-graben basins with continental clastic sediments under oxidative conditions and volcanic efflux volosts ; (2) low-angle detachment faults; (3) isomorphic granites; (4) metamorphic core complexes. These extensional structures have an NW-SE direction of extension at the regional scale. The detachment faults have NW-SE directions Of mineral stratigraphic line and upper NW-directed shear deformation. The mineral stratification of syntectonic granites is NW-SE as well, but appears as shear deformation of the upper NW or SE. The results of isotope chronological measurements Indicating that the deformation time is 130 ~ 120Ma. These extensional activities led to the rapid uplifting and reenforcement of isomorphic granites and core complexes.According to the developmental characteristics of magmatic rocks and the extensional tectonics of Liaodong Peninsula and the magmatic role in time and space, Tung failure can be divided into weak extensional Jurassic crust and Cretaceous strong crust stretching two stages.