贵州南部碳酸盐岩地震“亮点”与油气意义

贵州南部海相碳酸盐岩沉积区,在可控震源与炸震源的地震普查勘探中,由于反射振幅的变化,在地震反射剖面上,出现了强振幅异常,有“亮点”、“平点”与“暗点”。对其显示的地点和层位,进行了沉积环境、岩层特征、油气生成条件、有机质热演化程度、构造固闭情况等的综合对比分析,认为强振幅形成的“亮点”,可能为储气层的显示;水平反射显示的”平点”,可能是含气储层与不含气层之间形成的波阻抗界面;反射振幅减弱形成的“暗点”,可能为岩性变化的层间反映。

THE SIGNIFICANCE OF SEISMIC "BRIGHTSPOT" SHOWED iN CARBONATE ROCKS ON HYDROCARBON, SOUTHERN GUIZHOU

In seismic reconnaissance prospecting with controlled source and detonation source in carbonate rocks area of Southern Guizhou, as variation in reflection amplitude, "bright spot", "flat spot"and"dim spot" display on reflection sections. For the position and horizon indicated by the above spots, we have a comprehensivea correlation and analysis on sedimentary environment, lithological features, hydrocarbon generating conditions, evolutionary level of organic material and structural traps. We consider that the "bright spot" from strong seismic amplitude perhaps may be an indication of gas reservoir and the "flat spot" from horizontal section may be the wave impedance boundary between gas bearing reservoir and non-gas bearing reservoir and the"dim spot" from the weakened reflection amplitude may be the interbedded reflection of lithologic variation.