摘要
花岗岩风化壳储层具有高孔、高渗和厚度大的特点,但受潜山岩性、顶面形态、暴露周期和构造运动改造的影响,储层物性横向变化较快,风化壳储层与下伏基岩体、上覆沉积地层的界面阻抗差异变化大,连续性不高,常用的地震属性及其分析方法、地震反演预测风化壳储层的精度不高,难以满足油气勘探、开发的需求。为此,综合花岗岩风化壳储层地质成因、叠置模式、保存条件、钻井资料和地震响应信息,分析了潜山顶面倾角、振幅和频率等属性间的关系和变化特征并融合,形成了一种无因次复合属性,该属性能够揭示基岩潜山风化壳储层厚度与物性变化。应用复合属性预测Bongor盆地RP油田风化壳储层分布,结果表明,钻井结果与风化壳储层厚度预测结果的吻合率较高,风化壳优质储层主要分布于潜山表层0~50 m的深度范围内,且随着埋深增大,风化壳储层发育程度逐渐降低,这一特征也得到后续钻井的证实。
The granite weathered crust reservoir is characterized by high porosity,high permeability,and large thickness,but the lateral change of the reservoir is fast because of the influence of the lithology of the buried hill,the top surface shape,the exposure period,and the tectonic movement.The interface impedance between the weathered crust reservoir and the underlying formation and overlying sedimentary strata varies greatly,and the continuity is not high.The accuracy of seismic attribute analysis and seismic inversion in predicting weathered crust reservoirs is not high,so it is difficult to meet the needs of petroleum exploration and development.Therefore,the geological origin,superposition model,preservation condition,drilling data,and seismic response of granite weathered crust reservoir are integrated,and the relationship and variation characteristics among the structural dip angle,amplitude,and frequency of the buried hills are analyzed and fused to form a dimensionless composite attribute,which can reveal the thickness and variation of physical properties of the weathered crust reservoir in the bedrock.The application of composite attributes to predict the distribution of weathered crust reservoirs in RP oilfield of Bongor Basin shows that the drilling results are in good agreement with the prediction of the thickness of weathered crust reservoir,and the high-quality weathered crust reservoirs are mainly distributed in the 0~50 m depth range of the surface layer in buried hills.The development degree of weathered crust reservoirs decreases gradually with the increase in burial depth,which is confirmed by subsequent drilling.
作者
魏小东
窦立荣
夏亚良
王景春
曾庆芹
赵治斌
WEI Xiaodong;DOU Lirong;XIA Yaliang;WANG Jingchun;ZENG Qingqin;ZHAO Zhibin(Oversea Business Department,Geophysical Research Institute,BGP Inc.,CNPC,Zhuozhou,Hebei 072751,China;PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;BGP International,CNPC,Zhuozhou,Hebei 072751,China)
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2023年第S01期77-82,共6页
Oil Geophysical Prospecting
基金
中国石油天然气股份有限公司专项课题“海外复杂裂谷盆地精细勘探关键技术研究”(2021DJ3103)资助。
关键词
构造倾角
振幅
频率
属性融合
风化壳
储层预测
Bongor盆地
structural dip angle
amplitude
frequency
attribute fusion
weathered crust
reservoir prediction
Bongor Basin
