Abstract:In terms of the attenuation difference which seismic waves of different frequencies cause in various rock formations, the author advanced a new seismic-trace analysis technique that is called pseudo frequency log (F-LOG). High attenuation index that indicates tenuation degree of relative high-fequency seismic content is obtained bV making frequency spectrum analysis of seismic traces. In order to remove the influence of unrelated factors, ratio is used. Thus, the high attenuation index only means relative degree. A F-LOG curve consists of high attenuation indexes of all sampling values of a seismic trace. Its relative high values indicate that the relevant fomation is relativelysoft, loose, or hydrocarbon bearing. Hence, F-LOG curves may be used to predict reservoir variation. It is discussed how we improve resolution and make horizon correlation of F-LOG curves. This method was used to analyse fractured-porous reef gas reservoir in Leping series, fractured-caved limestone gas reservoir in yangxin series, and fractured needle-like porous dolomite gas reservoir in middle-Triassic sVstem in Sichuan basin. Good effect was received.
徐中英. 应用地震道的F-LOG分析技术研究裂缝-孔隙性气藏[J]. 石油地球物理勘探, 1991, 26(4): 437-451.
Xu ZhongVing. A research on fractured-porous gas resservoir by F-LOG analysis of sismic traces. OGP, 1991, 26(4): 437-451.