JZ气田湖底扇岩性砂体沉积模式研究与应用  

Research and Application of Sedimentary Pattern for the Sub-Lacustrine Fan Lithologic Sandbody in the JZ Gasfield

作　　者：文佳涛 吕坐彬 韩雪芳 房娜 严皓 Wen Jiatao;Lyu Zuobin;Han Xuefang;Fang Na;Yan Hao(CNOOC(China)Tianjin Branch,Tianjin300459,China)

机构地区：[1]中海石油(中国)有限公司天津分公司

出　　处：《特种油气藏》2020年第1期75-81,共7页Special Oil & Gas Reservoirs

基　　金：国家科技重大专项“渤海油田高效开发示范工程”（2016ZX05058-001）

摘　　要：JZ气田是渤海油田的一个典型的湖底扇沉积气田,目前处于开发初期,湖底扇内部储层横向变化快,砂体分布范围和沉积模式认识不清,给储量计算和开发方案研究带来了严峻挑战。为解决上述问题,在探井资料少,井距大的条件下,充分利用地震沉积学方法,通过地震分频解释技术和方差体地震属性刻画湖底扇砂体平面分布范围;以单井相、测井相和地震相标志为基础,结合地震属性优选优势频带下的平均瞬时频率属性和地层倾角属性,进而刻画出湖底扇内扇、中扇和外扇亚相分布范围,建立了湖底扇精细沉积模式。结果表明:JZ气田在勘探阶段初步认为是一个连片分布、稳定沉积的湖底扇砂体,其实是由2个相互独立不连通的岩性砂体组成,主力湖底扇砂体的内扇亚相位于构造高部位的陡坡带,地震相较为杂乱,连续性差;中扇亚相面积相对较大,储层横向展布较为稳定,为气田有利储层发育区,开发潜力大;外扇亚相面积相对较小,储层整体不发育。研究成果为JZ气田的储量计算和开发方案编制提供了可靠地质依据。The JZ Gasfield is considered as a typical gas reservoir with sub-lacustrine fan sedimentation in the Bohai Oilfield,which is still in its initial development stage.The reservoir calculation and development program design are greatly challenged by large lateral reservoir variation and a short understanding in sandbody distribution range and sedimentary pattern.The seismic sedimentology method was fully used to solve the above problems under the condition of less exploration well data and large well spacing deployment.The lateral sub-lacustrine sandbody distribution was characterized by seismic frequency division interpretation technology and seismic attribute interpretation of variance cube.Based on the marks of single-well,logging and seismic facies,the average instantaneous frequency attribute and formation dip angle attribute in the dominant frequency band are optimized by combining with seismic attributes.Furthermore,the inner fan,middle fan and outer fan subfacies of the sub-lacustrine fan were characterized to establish a fine sedimentary pattern of sub-lacustrine.Result indicates that the JZ Gasfield which initially considered to be a sub-lacustrine sandbody with continuous distribution and stable sedimentation is composed by 2 isolated lithological sandbodies without connection.The inner fan subfacies of the major sub-lacustrine fan sandbody is located in the steep slope zone of high part,which is characterized by a relatively chaotic seismic facies and poor continuity.The middle fan subfacies is characterized by relatively large area and relatively stable lateral reservoir distribution,which is considered as a favorable zone with significant potential for gas reservoir development.The outer fan subfacies indicates a relatively small area with non-developed reservoir.This research could provide a reliable geological basis for the reservoir calculation and development program preparation in the JZ Gasfield.

关 键 词：湖底扇 岩性砂体 地震属性 储层预测 沉积模式 渤海油田 

分 类 号：TE122[石油与天然气工程—油气勘探]