Field Evaluation of Relative Permeability Modifier Effectiveness Through Integrated DTS and Production Logging Measurements

Abstract

High water cut in oil producing wells presents significant operational challenges and accelerates economic decline. Conventional mitigation methods are often non-selective, restricting hydrocarbon production and requiring costly workovers. A more targeted remediation approach combines coiled tubing (CT) production logging to identify water entry profiles with selective placement of relative permeability modifier (RPM) treatments. However, conventional CT logging can suffer from incomplete interval coverage due to friction‑lock and bottomhole assembly compression limitations. This paper presents a novel intervention methodology that integrates a hybrid CT system with targeted RPM agent placement. Separate pre and post treatment production logging runs were conducted to verify the effectiveness of the RPM deployment. The hybrid CT configuration consisted of a 2.0 in. CT incorporating a 4mm wire housing a triple fiber-optic cable. Multiple distributed temperature sensing (DTS) acquisitions were performed to enhance diagnostic capability and improve visualization of RPM placement. The DTS data provided continuous downhole temperature profiles, enabling post-job evaluation of fluid movement and stage coverage. The subject well exhibited a gradual increase in water cut, reaching approximately 70% after 45 years production. The intervention program comprised five stages. First, a production logging run was conducted to identify fluid entry and divided the water producing interval into two sections. Second, an RPM agent was squeezed across a 154 ft. open hole (OH) section from 6,283 to 6,435 ft. Third, hybrid coiled tubing was deployed to acquire DTS measurements across the identified water‑production zone. Fourth, the well was flowed back, and oil and water production rates were measured. After a 32 hours soaking period followed by approximately 55 hours of flowback, the oil to water production ratio exhibited a sustained upward trend, indicating partial effectiveness of the RPM treatment in reducing water production. The final stage involved post‑treatment production logging to evaluate RPM performance, which indicated an overall neutral treatment response. The coordinated application of DTS and PLT measurements supports precise RPM agent placement across the intended pay zone and confirms placement effectiveness without disrupting real‑time operations. This operational workflow also enables an alternative evaluation approach for selecting RPM products in mature wells with high water‑cut histories.