塔里木盆地古城地区鹰三段硅质含量分布预测与主控因素分析  

Quantitative prediction of siliceous content and its controlling factor in the third member of Yingshan Formation in Gucheng area,Tarim Basin

作　　者：徐兆辉[1] 王露[1] 曹颖辉[1] 李洪辉[1] 闫磊[1] 王珊[1] 赵一民[1] 杨敏[1] XU Zhao-hui;WANG Lu;CAO Ying-hui;LI Hong-hui;YAN Lei;WANG Shan;ZHAO Yi-min;YANG Min(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China)

机构地区：[1]中国石油勘探开发研究院,北京100083

出　　处：《天然气地球科学》2020年第5期612-622,共11页Natural Gas Geoscience

基　　金：中国石油天然气股份有限公司重大科技项目“古老碳酸盐岩油气成藏分布规律与关键技术”(编号:2019B-04)资助.

摘　　要：自古城6井获得突破以来,塔里木盆地奥陶系鹰山组业已成为主力勘探层系,鹰三段是重点产层之一。钻井证实,古城地区奥陶系硅质含量普遍偏高。利用三维地震和钻测井资料,引入地震沉积学基本理论与方法,井震结合,应用-90°相位旋转、频谱分解、属性提取、RGB三色融合、主因子分析、回归拟合等技术手段,定量计算了目的层高硅质含量岩石平面分布,定性刻画了储层和断裂的平面特征,探讨了硅质含量与两者的对应关系。为了实现对硅质含量的定量计算和断裂储层的定性表征,将以上技术手段整合成"八步法"研究流程。研究表明,在研究区钻井中奥陶系鹰三段(以鹰三下亚段为主)广泛发育硅质,井内统计显示高硅质含量岩石厚度介于7.13~89.50 m之间,平均厚度为55.02 m;地震计算的厚度最大可逾百米,主要分布在研究区的东部。断裂(特别是长期活动断裂)是硅质的主控因素,断裂发育的地区高硅质含量岩石厚度大。硅质与储层的对应关系较为复杂,有效储层往往发育在高硅质含量岩石由厚减薄的地区。Since the breakthrough made in Well GC6,the Ordovician Yingshan Formation in Tarim Basin has become a major exploration formation,with the third member of Yingshan Formation(O1y3)to be one of the producing zones.It is proved by wells that siliceous content is commonly high in Ordovician of Gucheng area.Based on 3D seismic and well data,basic theory and methods of seismic sedimentology were introduced to cal⁃culate distribution of siliceous quantitatively and to characterize features of reservoir and faults in the target layer by such techniques as−90°phase rotation,frequency decomposition,attribute generation,RGB color blend⁃ing,principal component analysis,regression fit,et al.Relationship between siliceous content and reservoir and faults was discussed.In order to realize the purpose of quantitatively calculation of siliceous rock and qualitative⁃ly characterizing of reservoir and faults,the above methods were combined into an eight-step working flow.Re⁃sults show that the siliceous is very popular in the O1y3(mainly in the lower of O1y3,i.e.O1y3L).According to statistics from well data,thickness of high-siliceous rock varies from 7.13 m to 89.50 m,averaging 55.02 m.The siliceous rocks are mainly distributed in the east of the study area,which can be more than one hundred me⁃ters thick according to the seismic data.Faults,especially long-period active faults are the main controlling fac⁃tor of the distribution of siliceous.Thickness of high-siliceous rocks is obviously larger than that in other areas.Relationship between siliceous and reservoir is much more complicated.It seems that,effective reservoir is usu⁃ally located in areas where the high-siliceous rock become thinner.

关 键 词：塔里木盆地 古城地区 鹰三段 硅质含量 主控因素 地震沉积学 

分 类 号：TE122.2[石油与天然气工程—油气勘探]