渤南低凸起北坡坡折带特征及其沉积充填响应
Characteristics of Slopebreak Zone and Its Deposition Response in the North Slope of Bonan Low Uplift

摘要： 渤南低凸起北部东二下段发育多种类型的沉积体，与坡折带的结构与演化密切相关。东二下段沉积时期，渤南低凸起北部斜坡带发育一个完整的坡折带沉积旋回：坡折带演化早期，即东二下段沉积早期，渤南低凸起北部斜坡上有断裂活动，斜坡坡度较大、起伏不平，发育一些古沟谷与洼地，其内堆积了近源碎屑物，在地震剖面上可见古沟谷内充填杂乱或蠕虫状地震反射体；坡折带演化晚期，即东二下段沉积晚期，伴随着准平原化斜坡被填低补齐，演变为沉积物的搬运通道，碎屑物借道斜坡被带到洼陷内部沉积，发育一系列高角度前积地震反射体。东二下段沉积早期斜坡内部古沟谷充填的杂乱或蠕虫状的地震反射体为近源快速堆积的产物，主要分布在第一坡折带内；东二下段沉积晚期洼陷内部发育的高角度前积地震反射体为远源沉积，主要分布在第二坡折带内。渤南低凸起北部斜坡带发育典型的坡折带演化旋回，空间上不同成因地震异常体从斜坡带向洼陷内转移，共同构成一组具有成因联系的坡折带-沉积复合体。
Abstract: There were several different kinds of sedimentary bodies of E3d2 in the northern Bonan Low Uplift which were closely related to structure and evolution of slopebreak zone. It developed a complete slopebreak zone sedimentary cycle of E3d12 in the northern Bonan Low Uplift. In the early stage of the evolution, (iethe early E3d12 period) some ancient gulchs filled with vermiform, chaotic anomalous bodies and lowlying lands developed in slope with submarginal sedimentation. In the late stage of the evolution, (iethe late E3d12 period) after the peneplanation process, the slopebreak zone became the channel of sedimentary deposited in the sub sag area and a series of highangle foresets were deposited within the channel. The anomalous bodies in the early time of evolvement of slopebreak zone were the rapid proximal sedimentary bodies，mainly distributed in the first slope break zone. And in late stage of the evolution, the anomalous bodies, mainly distributed in the second slope break zone, were the distal sedimentary bodies characterized by hightangle progradation. Above all, there were different kinds of sedimentary bodies developing in the northern Bonan Low Uplift from slope to depression during the whole slopebreak zone sedimentary cycle, making up the complex of slopebreak zone and deposition