Enhanced Flow Profile Evaluation by Combining Acoustic Noise Log and Thermal Modeling in Complex Design Wells

Abstract

The evaluation of injection efficiency is an important component of monitoring oilfield development; it is often complicated by well design, such as horizontal wells, dual or triple completions, and the use of inflow control devices (ICDs). This paper demonstrates how standard production logging (PL) measurements can be improved with the addition of a high sensitivity noise log and a quantitative temperature analysis that is sensitive to flow behind the tubing and casing. The latest generation noise tools are highly sensitive instruments that record data during multiple short duration stations. The tools acquire noise energy across a wideband spectrum ranging from 8 to 60,000 Hz. To improve interpretation and visualization, the noise data is separated into two displays: an ultra-low frequency narrowband spectrum (8 to 4,000 Hz) and a wideband spectrum (100 to 60,000 Hz). The implementation of high-resolution temperature data with thermal modeling enables improved multiphase flow profiling using the Joule-Thomson effect and near-wellbore temperature behavior in the surrounding formations. The integration of the noise tool and temperature modelling enables the detection of very low rate fluid flow that is not otherwise detectable with conventional production logging tools (PLT) and the quantification of multiphase flow behind the pipe in multi-barrier completions. This paper includes three case studies that demonstrate the integration of noise spectral data, temperature modeling, and spinner data. The first case is a single-string vertical injector well with separate injection at various layers. In this case, the well completion was challenging because the upper production interval was located behind the tubing. In the second example, the injection distribution changes under different flow rate conditions. At a high injection rate, the formation fracture pressure is exceeded; at low flow, the injection is below the fracture pressure. These results demonstrate that it is possible to qualitatively determine all injection intervals by noise logging and to quantitatively estimate the fluid distribution by thermal modeling, which was used to plan successful well workovers and restore injection. This technology identified zones that were taking injection that other conventional tools failed to identify, significantly improving the understanding of water injection conformance in the super giant Burgan field waterflood.