Abstract: The restoration of sedimentary palaeogeomorphology,an important aspect of source-sink system analysis,is helpful for the reconstruction of the sediment transport path system. It is crucial to study the distribution and evolution of ancient drainage systems, sedimentary systems and reservoir development in sedimentary basins. This paper summarizes the common methods and research progress of palaeogeomorphology restoration. The residual thickness method,impression method,back stripping and filling method,sedimentology method,sequence stratigraphy method,and geophysics method, etc., are the common methods used to restore sedimentary palaeogeomorphology. In the process of palaeogeomorphology restoration,the factors such as tectonic subsidence differences,compaction,stratum erosion and palaeowater depth should be considered to restore the original sedimentary thickness and quantitatively restore the sedimentary palaeogeomorphology. In the future,the study of palaeogeomorphology will gradually develop in the direction of multidisciplinary theory intersection,multi-method comprehensive analysis and multi-data application verification. The Lixian slope in the Raoyang sag was NNE-trending,west-uplifting and east-dipping,and south-gentle and north-steep before the deposition of the First Member of the Paleogene Shahejie Formation. From west to east,it is devided into the uplift area,slope area and trough area. The distribution of sand bodies was obviously controlled by the geomorphology. The slope area was controlled by two slope breaks,and the sandy sediments were more easily developed in the gentle slope zone. The multiple sets of NE-trending normal faults in the trough area led to the semi-graben geomorphology,which limits the development and distribution of sand bodies. It is easier to accumulate sandy sediments in the lower terrain and near the faults. These sand bodies that are continuously distributed in the plane can be regarded as potentially favorable reservoirs.

Key words: palaeogeomorphology, compaction correction, original deposition thickness, Shahejie Formation, Raoyang sag, Bohai Bay Basin

摘要： 沉积古地貌的恢复有助于重建沉积物搬运路径系统,是源-汇系统分析的重要内容,对研究沉积盆地古水系和沉积体系分布演化以及储层发育至关重要。文中梳理了恢复古地貌的常用方法及其研究进展,明确残余厚度法、印模法、回剥和填平补齐法、沉积学法、层序地层学法、地球物理学法等是恢复沉积古地貌的基本方法,认为在恢复沉积古地貌过程中还应考虑构造沉降差异、压实作用、地层剥蚀和古水深等因素影响,未来古地貌研究将逐渐向多学科理论交叉、多方法综合分析、多资料应用验证的方向发展。饶阳凹陷蠡县斜坡沉积古地貌研究表明:沙一段沉积前该地区为北北东走向、西抬东倾、南缓北陡的斜坡,自西向东依次为凸起区、斜坡区和洼槽区;地貌对砂体的分布有明显的控制作用,斜坡区受2条坡折带控制,在坡度较缓处更易发育砂质沉积物,而洼槽区多组北东向正断层形成的半地堑组合地貌限制了砂体的发育,但在地势较低处和靠近断层处更易堆积砂质沉积物,这些砂体在平面上呈连片状,可作为潜在的有利储集层。

关键词: 古地貌, 压实校正, 原始沉积厚度, 沙河街组, 饶阳凹陷, 渤海湾盆地

CLC Number: 

• P531