莺歌海盆地深层“暗点”型隐蔽圈闭识别方法  

Dim spot subtle trap identification in Yinggehai Basin

作　　者：潘光超 邓勇 范彩伟 朱沛苑 吴涛 

机构地区：[1]中海石油(中国)有限公司湛江分公司,广东湛江524057

出　　处：《石油地球物理勘探》2018年第5期1014-1021,1030,共9页Oil Geophysical Prospecting

基　　金：国家科技重大专项"莺琼盆地高温高压天然气富集规律与勘探开发关键技术(三期)"(2016ZX05024-005)资助

摘　　要：莺歌海盆地深层具备油气勘探潜力。通过岩石物理及地震正演模拟分析,明确了深层高温超高压领域含气储层地震反射特征及"暗点"型目标的勘探意义,分析了"暗点"型目标的识别难点。在此基础上,提出了"暗点"型目标识别三步法:(1)"暗点"识别,利用本文提出的FN属性识别出常规叠加剖面上具有Ⅱ类AVO异常的地震弱反射特殊异常体;(2)岩性识别,利用砂、泥岩纵、横波速度比的差异识别储层,剔除特殊岩性体造成的假FN属性异常;(3)物性预测,利用砂岩孔隙度与纵、横波阻抗的线性关系预测储层物性,识别"甜点"储层。该方法应用到乐东S区,成功发现乐东10-X"暗点"型目标,经钻探证实了方法的可行性和有效性,并值得进一步推广。Deep strata in Yinggehai Basin have good hydrocarbon potentials.Seismic reflection characteristics of gas reservoir and dim spot targets in deep high-temperature and ultra-high pressure are clarified based on rock physics analysis and seismic forward modeling.Difficulties in dim spot target identification are also discussed.Based on our mentioned research,we propose a three-step approach of dim spot target identification.The first step is dim spot identification.Weak reflection bodies with AVO type 2 anomaly on stack sections are considered as dim spots based on FN attribute.The second step is lithology identification.The reservoir identification is achieved with vP/vSdifferences between sandstone and mudstone,and false FN attribute anormalies caused by other lithology are eliminated.The third step is physical properties prediction,which is achieved with the linear relationship between sandstone porosity and P-and S-wave impedances,and sweep spots are identified at the same time.The proposed approach is applied to the Block Ledong and Ledong 10-X dim spot is identified.The latest drilling proves the feasibility and effectiveness.

关 键 词：莺歌海盆地 “亮点” “暗点” 深层高温超高压领域 隐蔽圈闭 低孔低渗 

分 类 号：P631[天文地球—地质矿产勘探]