常年流水型砂质辫状河心滩坝内部落淤层展布样式探讨

利用露头和现代沉积资料,综合前人研究成果,分析认为常年流水型砂质辫状河落淤层的展布特征主要受心滩坝演化以及后期多次冲刷改造的影响,其中心滩坝演化对落淤层分布的影响最为重要。在此基础上,利用沉积学原理,重点从心滩坝演化的角度出发,通过单因素分析、多因素组合讨论了不同沉积作用条件下落淤层的保存及分布,建立了落淤层的3种总体分布样式,即近穹窿式、近水平式和单向倾斜式,并给出了地下表征的基本思路。这一研究可以为地下同一沉积模式的砂质辫状河储层内部落淤层的精细表征提供模式指导。

Distribution patterns of the fall-siltseams in the channel bar of the perennial sandy braided river: An approach

According to the sedimentological principles and existing data, the preservation and distribution of the fall-siltseams in the channel bar of the perennial sandy braided river are discussed in this study with the aid of monofactor and multi-factor analysis, and three types of distribution are constructed for the fall-siltseams, i. e., the fornix type, subhorizontal type and monoclinal type. These distribution patterns of the fall-siltseams are mostly influenced by the channel bar evolution and successive erosion and reworking in the perennial sandy braided channels. The results of research in this study have assisted in the refinement of the model for the fall-siltseams in the subsurface sandy braided river reservoir rocks, and thus have important practical significance.