合成记录制作中井眼影响因素分析及对策

Analysis of borehole factors in synthetic seismogram building and countermeasures

通过制作合成地震记录来标定准确的时深关系是层序地层对比和储层反演的基础。分析合成记录制作中的声波和密度测井曲线受到诸如井眼状况、油气、泥浆侵入及浸泡程度等因素的影响,提出利用井径曲线和深中浅电阻率来综合指示判断这些影响的大小,讨论了声波曲线重构时电阻率和声波曲线的探测深度匹配问题。在合成记录制作完成后,利用多井时深关系对比可以检查所制作的合成记录是否受到了各种测井不利因素的影响,从而判断时深关系的可靠程度,为储层反演和精细目标预测打下良好基础。

Precise Time-Dpeth relationship derived from synthetic seismogram making is the base of sequence stratigraphic correlation and reservior inversion. Sonic and density logs used for seismogram making are subjected to the influence of factors such as borehole conditions, presence of hydrocarbon, mud invasion, degree of such invasion etc. Caliper log and deep-middle-shallow resistivity logs are proposed to monitor the impact of such factors and necessary corrections should be made before sonic and density logs are used in building synthetics. When a pseudo-acoustic log is reconstructed from a resistivity curve, investigation depths of acoustic and resistivity logs must match each other. Finally when synthetic seismograms are successfully built, the time-depth relationships obtained can help us to check whether the adverse influences of the various factors have been completely eliminated, so as to ensures precise reservoir inversion and target prediction.