Application of fullbore formation microimager logging in the evaluation of anisotropic resistivity in a thin interbed reservoir

摘要

Oil and gas reserves in sand-shale thin interbeds are extensive, but it is a challenge to achieve satisfactory precision in the identification of these interbeds using traditional logging data. Phasor induction and three-component induction logging are appropriate tools for the identification of sand-shale interbeds. Unfortunately, phasor induction data are expensive and three-component induction logging is rarely used in major domestic oil fields. As a result, evaluation of sand-shale thin interbeds heavily depends on a traditional logging suite, general image logging, array lateral logging and array induction logging, and so on. In this paper, we investigate the sand-shale thin interbed region in the northern part of the Sulige field. We propose a comprehensive method of anisotropic evaluation which is based on the combination of wellbore microresistivity image logging (fullbore formation microimage (FMI)) and high-resolution array induction logging (HRLA), where HRLA can be used instead of a traditional logging suite or high-resolution array lateral logging. The proposed method works well in the evaluation of thin interbeds in the northern part of the Sulige field. In this paper, the combination of FMI and deep resistivity of HRLA is used. It should be noted that it is possible to use deep resistivity of conventional laterolog or array induction log instead of HRLA.