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中蒙边界地区在晚侏罗世晚期—早白垩世发育一个广阔的伸展盆地体系,内部由许多不同规模的次级盆地所组成。盆地体系大致经历了两个发展阶段,早期阶段普遍发育相互独立的次级盆地,而晚期阶段则发生以次级盆地侧向相互连接为特征。相互连通的次级盆地进一步演化为大型次级盆地,形成盆地体系内的沉积和沉降中心,并在平面上呈条带状。与此同时,由于应力逐渐集中在大型次级盆地边界断层之上,处于应力影中的次级盆地停止发育。中蒙边界地区晚中生代的伸展盆地体系的形成与地壳浅部的伸展作用相关,动力学成因机制很可能与增厚岩石圈的重力垮塌有关。
In the Late Jurassic-Early Cretaceous, a broad extensional basin system was developed in the border area between China and Mongolia, and the interior was composed of many secondary basins of different sizes. The basin system has undergone two stages of development in general, with independent secondary basins generally developed in the early stages and late-stage secondary lateral basin interconnections. The interconnected secondary basins further evolve into large secondary basins, forming sedimentary and subsidence centers within the basin system and are strip-like in plane. At the same time, the secondary basins in stress shadows stopped developing due to the gradual concentration of stress on the boundary faults in the large secondary basins. Late Mesozoic extensional basin formation in the Sino-Mongolian border region is related to the extension of the shallow crust. The dynamical mechanism is probably related to the gravitational collapse of the thickened lithosphere.