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

Abstract

Proper hydrocarbon field management requires evaluating downhole production and injection efficiencies. This process can however be very challenging in many well configurations with behind pipe or formation flow, such as horizontal wells, wells with inflow control devices (ICDs), or in dual and triple string completions, especially when using standard logging techniques. This paper highlights how additional measurements, such as high-sensitivity spectral noise and fast-response temperature, can improve the quantitative analyses obtained with conventional production logs (PLT). Production log analysis typically provides very reliable flow profiles inside the wellbore, but much of what is going on behind the pipe or directly in the formation around the well is hidden from the PLT sensors. The downhole flow environment is more completely characterized, however, by complementing the PLT analysis with spectral noise and thermal modelling, and current technology makes this possible on a single run in the well. Several regional cases are presented to show the technology and the results from the individual analyses, demonstrating how they can be integrated to improve the understanding of the downhole panorama. The case studies presented in the paper were selected from some of the more complicated operating environments in UAE production wells and are used to demonstrate how spectral noise and temperature data can successfully complement the downhole analyses obtained from specialized production logging sensors in these high-angle wells. The noise tools used for these logs are highly sensitive instruments recording across a wideband frequency spectrum to acquire noise signatures from very small fluid movements in and around the wellbore. The addition of thermal modeling on the high-resolution temperature data improved the flow profiling in the surrounding formations. The presented cases include producer wells, along with different types of lateral completions. Objectives among the examples also vary, showing production profiling, investigation of formation fluid movement, evaluation of flow behind casing, and diagnosis of leaks in the completion. The acquisition of data sets with different types of sensors not only helped improve the dynamic downhole analyses but also enabled corroboration of the responses among the tools, ultimately increasing the reliability of the interpretations provided to the well operator in these complex conditions. The case studies presented will demonstrate how operators can benefit from the effective use of the latest generation of spectral noise tools to qualitatively identify production intervals, in combination with thermal modelling to quantitatively estimate fluid distribution, and with production log data for wellbore flow and fluid profiling. The improved understanding of the downhole fluid dynamics is used to program more informed interventions, optimizing production efficiency, and overall field and reservoir economics.