摘要
在扩径、压实不好和井壁不规则的井段,用单发双收声波测井资料求的孔隙度往往偏大。目前一般用压实系数CP或附加校正参数ACC进行校正。由于取值缺乏客观依据,结果也不合理。本文阐明了井壁不规则、压实不好及扩径对单发双收声波测井影响的机理,提出了相应的校正方法,进行了理论上推导,并从仪器结构原理的角度加以说明.同时,用计算机对井壁不规则的影响进行了考察,还给出了井壁不规则、扩径和压实校正的实例。
Porosity derived from acoustic log with single transmitter and dual receivers tends to behigher in enlarged, rugose borehole drilled through badly compacted formation. Correctionis now normally made with compacting factor CP or additive correction factor AAC. Sincethe parameters taken do not ground on the objective fact, the result is not reasonable. Theeffect of bad compaction, enlarged and rugose borehole on the log is presented and a newcorrection method is proposed. The new method is described from the view point of the con-figuration of the tool along with theoretical derivation. And the effect of rugose borehole isanalysed with computer. Examples of new correction method are given.
