孟加拉扇更新统加积型深水水道规模和演化  

Scale and Evolution of the Pleistocene Aggradational Channels in the Bangle Fan

作　　者：许小勇 张颖 鲁银涛 马宏霞 闫春 刘忻蕾 徐宁 邵大力 孙辉 丁梁波 XU Xiaoyong;ZHANG Ying;LU Yintao;MA Hongxia;YAN Chun;LIU Xinlei;XU Ning;SHAO Dali;SUN Hui;DING Liangbo(PetroChina Hangzhou Research Institute of Geology,Hangzhou 310023,China;North China Institute of Science and Technology,Langfang Hebei 065201,China;China National Oil and Gas Exploration and Development Corporation,Beijing 100031,China)

机构地区：[1]中国石油杭州地质研究院,浙江杭州310023 [2]华北科技学院,河北廊坊065201 [3]中国石油海外勘探开发公司,北京100031

出　　处：《地球科学进展》2022年第3期268-276,共9页Advances in Earth Science

基　　金：国家自然科学基金项目“孟加拉湾东北部深水沉积体系发育特征与生物气成藏规律研究”(编号:42076219)和“孟加拉湾东北部沉积过程与特提斯东段构造变形耦合关系”(编号:92055211)资助。

摘　　要：近年来,深水油气勘探发现的储量在全球新增储量中的占比逐年增加,2010年以来其占比已超过50%,深水已经成为未来油气勘探的重点领域。作为深水油气勘探主要储层之一的深水水道,同样成为深水油气勘探的重点研究对象。以高分辨率(40 Hz)三维地震资料为基础,对研究区内的加积型水道—天然堤复合体进行了精细刻画,着重刻画了水道—天然堤复合体内部不同期次水道的中心线,重点分析了深水水道的发育和演化特征。该水道天然堤复合体整体宽25~30 km,单期水道宽度约300 m,推测厚度约10 m。深水水道的演化整体表现为有序的发育过程,初期水道较顺直,弯曲度较低,后期弯曲度逐渐升高,晚期水道的平面形态较为稳定,变化较小。深水水道在演化过程中不仅向左右两侧迁移,同时也具有向下游方向迁移的特征;前人认为深水水道向下游迁移的现象非常罕见,但是研究表明在某些情况下,这种现象可能并不罕见。Recently,the proportion of deep-water incremental reserves has increased gradually each year.This proportion has exceeded 50%since 2010.Deepwater environments have become a key area of future oil and gas exploration.As one of the main reservoirs for deep-water oil and gas exploration,deep-water channels have attracted increasingly more attention.Based on high-resolution(40 Hz)3D seismic data,this study carried out a detailed description of an aggradational channel-levee complex in the study area.The centerlines of the different channels in the complex were recognized from bottom to top.The overall width of this channel-levee complex is 25~30 km.The width of the single-channel is about 300 m,and the thickness is estimated to be 12 m.The channel morphology of this complex shows an organized evolution.The channel was relatively straight with low curvature at the beginning of aggradation,and the curvature gradually increases over time.During aggradation,the deep-water channels not only swing but also sweep downstream.Predecessors believed that downstream sweep is very rare in deep-water channels;however,our research shows that this phenomenon may be common under some special conditions.

关 键 词：孟加拉扇 更新统 深水 水道中心线 水道演化 

分 类 号：P618.13[天文地球—矿床学]