水平井双侧向测井响应及层厚/围岩影响快速校正

建立上下3层介质的水平井模型,采用三维有限元方法研究水平井双侧向测井响应.结果表明,水平井双侧向测井响应受井眼位置的影响,井眼位于目的层不同垂向位置时,非厚层的双侧向测井响应差异明显;不同层厚及围岩条件下水平井双侧向测井响应与直井差异较大,且在无侵入条件下深浅侧向电阻率显示明显的幅度差异.在三维数值计算的基础上,建立水平井双侧向测井层厚及围岩影响校正图版,并据此研究水平井双侧向测井层厚及围岩影响校正快速计算方法.利用快速校正公式计算得到的校正图版与基于三维数值计算的校正图版具有很好的相似性,说明该方法可快速、有效地实现水平井双侧向测井响应的层厚及围岩校正.图5表4参15

Response of dual laterolog and fast correction for layer thickness and shoulder bed in horizontal wells

Based on horizontal well modeling with 3 layers, the 3D finite element method is used to simulate the response of dual laterolog in horizontal wells. The modeling results show that the response of the dual laterolog is obviously influenced by the borehole position in the target formation. When the borehole position varies, the dual laterolog response of non-thick formation changes. Under conditions of different layer thicknesses and/or different borehole positions, the responses of dual laterolog in horizontal wells are different from that in vertical wells. The deep and shallow resistivity of the dual laterolog exhibits an apparent amplitude difference for the non-invaded zone in horizontal wells. Based on the 3D numerical simulation results, the correction charts of dual laterolog responses for layer thickness and shoulder bed are generated, and a fast calculation method for resistivity correction in horizontal wells is proposed. The correction results from proposed method agree well with those from 3D numerical computation. The fast correction method is rapid and effective in layer thickness and shoulder bed correction.