测井资料与应用 -3-课件.pptVIP

测井资料与应用(3);2.5 声波测井 (Acoustic Log);2.5.1 测量原理;Full wave form;常规声波测井一般提供声波时差Δt ;不同的地层具有不同的声波速度和时差Δt;2.5.3 声波孔隙度;2.5.4 应用;Wyllie 平均时间公式 ( WTA ) 最常用的孔隙度公式 : ?s = 式中, △tma 纯地层骨架的声波时差 ; △tf 孔隙流体的声波时差; Cp 压实校正系数 . ;压实校正; 压实校正图版 范例砂岩 Δt = 110 μs/ft不校正 : Φ = 40%选择 Cp = 1.5 : Φ ≈ 27%;泥质影响校正; 油,气影响校正 油,气的? t大于水 --- 油/气层处理出的 ΦAC 偏大 油,气影响校正 系数: 气层 Φt = 0.7 × ΦAC 油层 Φt = 0.9 × ΦAC ;GR;研究岩石的物理特性;Borehole Breakout;地层出砂分析;用斯通利波计算渗透率;;;2.6 电阻率测井;;不同地层的电阻率 ;Presentation;;2.6.3 Dual Lateral Resistivity Tool;;* 8 Rt curves with different investigation depth (10 – 120 in) * The logging curves separate in the permeable zone. * The invasion pro us the flushed zone, transition zone and virgin zone. ; Use focused current* Very shallow  investigation (2-12 in)* Measure Rt of  flushed zone ( RXO)* Used for evaluation  of invaded affection ;2.6.6 环境影响; 主要的环境影响 ● 井眼垮塌 ● 电阻率差异大的围岩 ● 泥浆侵入. ;The affection of bed thickness;Bed thickness Correction ( Induction log ) Bed thickness 6 ft No correction Thinner beds need more correction Different Rs need different correction ;Chart for borehole correction to dual lateralExamplegive:Rm = 1?mRD = 10 ?mborehole = 11inRLLDcorr  ≈ 10 × 1.4  ≈ 14 (?m); Water zone  Salty mud (Rm Rw, low Rt  invaded ) :  Ra Rxo Rm  Fresh water mud (Rm Rw,  high Rt invaded ) : Ra Rxo RmOil zone Salty mud (Rm Rw, low Rt  invaded ) :  Ra Rxo Rm  Fresh water mud (Rm Rw,  high Rt invaded) : Ra Rxo Rm  Ra – apparent log resistivity Rxo – flushed zone resistivity Rm – mud resist