高分辨率阵列侧向测井井眼影响自动校正研究

Auto-correction of borehole effect for high-resolution array laterolog

阵列侧向测井具有较高的纵向分辨率,在径向上可以提供多种探测深度的测量曲线,为地层侵入剖面的描述提供更加详细的信息,但其测井结果不可避免地会受井眼的影响,特别是浅探测深度的测井结果受井眼影响尤为严重;因此,需要对其进行井眼校正。文中以斯伦贝谢公司推出的高分辨率阵列侧向测井仪HRLA为例,在分析阵列侧向测井井眼影响的基础上,对HRLA的井眼校正图版进行数字化,然后优选Akima插值算法实现了图版曲线高精度插值拟合,利用网络加权分析实现了井眼影响的自动校正,并编制程序对实际阵列侧向测井资料进行自动连续校正处理。应用结果验证了对井眼影响规律的分析。校正结果表明,该校正方法和处理程序提高了井眼校正的精度和效率,具有良好的实用性。

The array laterolog not only processes superior vertical resolution but also provides various measured curves of different depth on the radial, offering more detailed information for the description of invasion profile within the formation. However, the logging result is inevitably affected by the borehole, especially for the shallow lateral logging. Hence, borehole correction is demanded. This paper focuses on the high-resolution influence caused by the HRLA, an array lateral logging instrument provided by Schlumberger. On the basis of analyzing the result of array laterotog borehole, we digitalized the HRLA borehole correction chart and optimized Akima interpolation algorithm for automatical correction. The auto-correction of borehole effect was achieved by network weight analysis, and the automatic successive correction of practical array lateral logging data was programmed. The analysis of influence rule was verified by the reasonable application results. The correction method and processer improve the accuracy and efficiency of borehole correction with high practicability.