Conventional resistivity tools often miss hydrocarbon payrnzones in thinly laminated sand-shale sequences. Incorporationrnof formation resistivity anisotropy into a petrophysical modelrnallows for a significantly more accurate means to estimaternhydrocarbon reserves in low-resistivity reservoirs. Torncorrectly determine the anisotropy distribution around thernborehole, an interpreter must use the multi-componentrninduction logs acquired with the application of the newrn3DEX tool.rnIf the multi-component induction measurements are notrnavailable, an interpreter should consider some alternative waysrnto determine anisotropic properties of the formation.rnIn this paper, we propose two new methods to estimaternresistivity anisotropy using vast logging data from the ArrayrnLateral Log (High-Definition Lateral Log - HDLL) and ArrayrnInduction Log (High-Definition Induction Log – HDIL) tools:rn?? The first method is based on a sequentialrninterpretation of the HDIL and HDLL data. It doesrnnot require layer selection for formation modelrndefinition. It is very fast because it uses sequentialrninduction and galvanic data processing as well asrnshort inversion windows.rn?? The second method utilizes borehole-corrected lateralrnresistivity (LR) logs and vertical resolution matchedrn(VRM) focused logs. The method does not requirernapplication of inversion-based processing andrnprovides anisotropy values at every logging point.rnThis approach is extremely fast.rnWe evaluate and compare the anisotropy interpretation resultsrnderived from the application of these methods. We use arn150-foot portion of a single data set acquired in a verticalrnoffshore well in the Mediterranean region. This uniquernlogging data set contains various different array resistivityrnlogs. We show that both methods supply an interpreter withrnanisotropy estimates within time limits imposed by real-timernwell-site processing.
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