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构造运动造就的古地貌在陆相盆地 ,特别是裂谷盆地对层序形成与发育起着重要的控制作用。裂陷扩张早期 ,凸起前发育下切河谷充填作用 ,前缘发育扇三角洲体系 ;当陆源碎屑补给缺乏时 ,局部隆起的水下平台区发育滨、浅湖滩坝或生物碎屑滩体系。裂陷扩张早中期 ,基准面上升时期凸起区为盆地主要物源区。受长期活动的边界基底断裂规模、性质、活动强度的控制 ,盆地边缘发育 3种类型的古地形坡折带 ,分别控制 3种类型沉积体系的形成。断崖型坡折带发育近岸水下扇沉积体系 ;断阶型坡折带发育斜坡扇体系 ;陡坡型坡折带发育扇三角洲及前方的盆底扇体系。基准面下降时期盆地充填作用增强 ,受凸凹相间分布的宏观地貌特征控制 ,凸起前缘发育扇三角洲体系 ,凸起间鞍部地区沿盆地长轴方向发育外源大型河流 -三角洲体系。
The paleogeomorphology created by tectonic movement played an important role in controlling the formation and development of sequence in the continental basins, especially the rift basins. In the early stage of rifting and expansion, the undercutting valley filling was developed before the bulge, and the fan delta system was developed on the front edge. When the supply of terrestrial debris was lacking, the coastal and shallow lake dams or bioclastic beach systems were developed in the partially uplifted underwater platform area. In the early and middle stages of rifting and dilation, the raised area during the rising period of the datum was the main source area of the basin. Under the control of the scale, the nature and the activity intensity of the long-term boundary basement rupture, three types of palaeo-slope break belts were developed on the margin of the basin to control the formation of three types of sedimentary systems. Cliff slope slope break develops near-shore submarine fan sedimentary system; fault-step slope break belt develops slope fan system; steep slope slope break belt develops fan delta and anterior pelvic floor fan system. The basin filling effect is enhanced during the period when the datum is falling down. It is controlled by the macroscopic topographic and geomorphologic features distributed between the convex and concave phases. The fan delta system is raised in the raised front and the extrinsic large river delta system developed along the long axis of the basin in the raised saddle area.