摘要
烃类异常会引起地震振幅变化,因此地震振幅常可用于油气预测。然而储层地震振幅不完全与流体特征相关,而是受到多种因素尤其是储层厚度的影响,解释多解性和不确定性不可避免。为提升油气预测准确度,本文提出一种基于振幅拟合的新的流体识别因子提取方法,通过将地震振幅分解为不同厚度砂体振幅与流体识别因子的乘积,利用砂体瞬时频率、砂体时间厚度与砂体真实厚度良好的相关关系拟合得到不同厚度砂岩的地震振幅,然后在实际振幅中弱化厚度变化带来的影响,进而得到流体识别因子。该因子弱化了储层厚度对地震振幅的影响,可有效提高单砂体油气预测的准确度。模型测试及在渤海油田中的实际应用显示了方法的有效性。
Hydrocarbon anomalies can cause changes in seismic amplitude,so seismic amplitude is often used for oil and gas prediction.However,the seismic amplitude of reservoir is not completely related to fluid properties but greatly affected by many other factors,especially reservoir thickness.Thus,multiplicity and uncertainty of hydrocarbon prediction by seismic amplitude are inevitable.In order to improve the accuracy of hydrocarbon prediction,this paper proposes a new method for extracting fluid identification factor based on amplitude fitting,which decomposes the seismic amplitude into the product of amplitude of sand bodies of different thicknesses and the fluid identification factor.Seismic amplitudes of sandstone of different thicknesses are obtained by fitting the good correlation among instantaneous frequency,time thickness and actual thickness of sand body,then the influence of thickness changes can be weakened in the actual amplitude,thus the fluid identification factor is obtained.This factor eliminates the influence of reservoir thickness on seismic amplitude and can effectively improve the accuracy of hydrocarbon prediction of single sand body.Model test and field application in Bohai oilfield demonstrate the feasibility of this method.
作者
明君
王波
王建立
王林
MING Jun;WANG Bo;WANG Jianli;WANG Lin(CNOOC China Limited,Tianjin Branch,Tianjin 300459,China)
出处
《中国海上油气》
CAS
CSCD
北大核心
2023年第6期35-42,共8页
China Offshore Oil and Gas
关键词
油气预测
振幅拟合
流体识别因子
储层厚度
渤海油田
hydrocarbon prediction
amplitude fitting
fluid identification factor
reservoir thickness
Bohai oilfield
