地震岩石学在G区块岩性预测中的应用

Application of seismic petrology to lithology prediction in G Block

(1．中海石油(中国)有限公司湛江分公司,广东湛江524057;2．长江大学,湖北荆州434023)

Zhanjiang Branch,CNOOC,Zhanjiang 524057,China

地震岩石学研究分为微观和宏观两个层面。微观层面的地震岩石学研究岩石微观结构和地震弹性参数间的关系,为地震储层预测服务；宏观层面的地震岩石学研究岩相和地震反射特征之间的关系,为地震属性相分析和沉积解释服务。目前,宏观层面的地震岩石学研究尚没有形成一套明确的概念和成熟的方法。首次提出宏观层面的地震岩石学研究应以最小等时研究单元为基础、以测井岩石物理学研究为前提。虽然测井和地震资料的密切结合和统计分析仍是主要的研究方法,但这种统计必须建立在考虑地层成因进行分层、分区的基础上。在北部湾盆地涠西南凹陷G区块流沙港组一段进行了地震岩石学研究,较准确地预测了砂体平面分布规律。

Seismic petrology research includes micro-level and macro-level. Micro-level seismic petrology studies the relationship between rock micro structure and seismic elastic parameters,to serve for seismic reservoir prediction. Macro-level seismic petrology studies the relationship between lithofacies and seismic reflection characteristics,to serve for seismic attributes facies analysis and sedimentary facies interpretation. Till now,macro-level seismic petrology research doesn’t form a series definite concept and mature methods. We first proposed macro-level seismic petrology should be based on minimum isochronous research unit,and take petrophysics research as prerequisite. Though the combination and statistical analysis of logging data and seismic data are still the main research method,but the statistical analysis should be on the basis of layer and block classification with considering formation genesis. Finally,seismic petrology research was carried out in the 1st member of Liushagang Formation at G Block of Southwestern Weizhou Sag,Beibuwan Basin,which relatively accurately predicted the plane distribution of sandbodies.