方位电阻率成像测井仪ARI

Azimuthal Resistivity Imaging Laterolog Tool

文章介绍一种新型的侧向测井仪器─—方位电阻率成像测井仪（ARI）。这种仪器比侧向测井（DLL）有更高的垂直分辨率，并且围绕井眼得到深的方位电阻率测量值。在双侧向电极排列中结合12个方位电极，提供12个深的、定向的电阻率测量，而保留标准的深和浅的侧向测井。并在方位阵列中结合一种浅的辅助测量，使得方位电阻率测量的井眼影响得到完全的校正。这种仪器还具有对不均质和裂缝地层进行地层评价和裂缝倾角计算的成像能力。

A new generation of laterolog tool, the azimuthal resistivity imager (ARI) was introduced in this pa per. The tool makes deep azimuthal resistivity measuerments around the borehole with higher vertical re solution than the Dual Laterolog(DLL), Twelve azimuthal eletrodes are incorporated into the DLL array to provide 12 deep, oriented resistivity measurements whi1e retaining the standard deep and shallow lat erolog measurements. To allow full correction of the azumuthal resistivity for borehole effect, a shallow auxiliary measurement is incorporated on the azimuthal array. Although the full－coverage azimuthal resis tivity image has much lower spatial resolution than borehole microelectrical images, it complements these because of its lower sensitivity to shallow features, Evaluation of heterogeneous and fractUred formation, and computation of fracture dip are aplications of the toolls imaging capabilities and are discussed and illus trated with least examples. Other log examples cover thin bed response and corrections for Groningen and borehole effects, including that for eccentering of the tool in the borehole.