断陷湖盆沉积层序演化模式及主控因素分析

发布时间：2018-06-14 23:38

本文选题：沉积层序 + 演化模式　；参考：《科学技术与工程》2017年17期

【摘要】：渤海湾盆地是我国东部新生代发育的主要含油气断陷湖盆,具有十分可观的资源储量。为了更好地指导油气储层预测,辅助勘探方案的制订,通过黄河口地区丰富的高分辨率地震数据以及钻测井等资料,全面分析了渤海湾盆地黄河口西洼东营组沉积层序的时空演化规律及其主控因素间的作用关系,最终得出如下结论:研究区东营组可划分为3套三级层序,其中SQ3和SQ2进一步划分为湖扩域和高位域。层序内部主要发育扇三角洲、辫状河三角洲、曲流河三角洲和湖相四种沉积体系,从SQ3至SQ1呈明显的继承性发育特征。沉积层序演化过程主要受到了古地貌和基准面变化的控制,其中坡折带作为古地貌的重要表现,它的形态和规模成为控制层序和沉积体系的首要因素;其不仅为沉积物供给提供保障,而且成为沉积物的搬运和卸载有利场所;另一重要影响因素是基准面变化,它通过影响A/S的大小,控制沉积物的储存状态,形成不同类型的沉积组合,最终在两种因素的耦合下形成了黄河口西洼复杂的层序、沉积模式。北部陡坡带,层序地层以断失现象出现,主要发育曲流河三角洲沉积体系。中部砂质滩坝大面积发育,而在南部斜坡带不整合特征以地层超覆为主,并形成持续发育、规模较大的辫状河三角洲沉积体系。未来勘探目标可设定为分布在滨浅湖砂质滩坝中的有利储集砂体。
[Abstract]:The Bohai Bay Basin is the main oil-bearing faulted lake basin developed in the Cenozoic in the eastern part of China. In order to better guide the prediction of oil and gas reservoir and to formulate auxiliary exploration plan, the abundant high-resolution seismic data and drilling logging data are used in the Yellow River Estuary area. The temporal and spatial evolution of the sedimentary sequence of the Xiwa Dongying formation in the Huanghe River mouth of Bohai Bay Basin and the relationship between the main controlling factors are analyzed. The conclusions are as follows: the Dongying formation in the study area can be divided into three sets of third-order sequences. SQ3 and SQ2 are further divided into lake extension domain and high level domain. Four sedimentary systems, fan delta, braided river delta, meandering river delta and lacustrine facies, are mainly developed within the sequence, with obvious inherited developmental characteristics from SQ3 to SQ1. The evolution of sedimentary sequence is mainly controlled by the changes of paleogeomorphology and datum, in which slope break zone is an important representation of paleogeomorphology, and its shape and scale are the primary factors controlling sequence and sedimentary system. It not only provides a guarantee for sediment supply, but also serves as a favorable place for transport and unloading of sediment. Another important factor is the change of datum level, which controls the storage state of sediment by influencing the size of A / S. Different types of sedimentary assemblages were formed, and finally the complex sequence and sedimentary model of Xiwa in the Yellow River estuary were formed under the coupling of two factors. In the northern steep slope zone, sequence stratigraphy appears as fault loss, and the meandering river delta sedimentary system is mainly developed. A large area of sandy beach dam is developed in the middle part, while the unconformities in the southern slope zone are dominated by stratigraphic overburden, and a braided river delta sedimentary system with a large scale is formed. The future exploration target can be set as a favorable reservoir sand body distributed in shallow lake sandy beach dam.
【作者单位】：陕西延长石油(集团)有限责任公司研究院;中国地质大学(北京)海洋学院;中国地质调查局油气资源调查中心;
【基金】：国家科技重大专项(2011ZX05023-002-005)资助
【分类号】：P618.13

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