Advanced Multi-Lateral Monitoring Using Intelligent Inflow Tracers with Production Log Comparison in a Carbonate Reservoir

Abstract Production logging tools (PLT) have been the incumbent of downhole monitoring technology for decades. These tools, often used in conjunction with tractors in extended laterals, pinpoint the locations of water or gas breakthrough and map the flow profile across producing zones. However, the logistics of scheduling and mobilizing production logging equipment and personnel are cumbersome and time-consuming. Acknowledging these challenges, alternative downhole monitoring technologies had to be explored to circumvent the limitations associated with PLT monitoring. The innovative approach involved deploying a smart multi-lateral well system with inflow control valves (ICV), annular and tubing pressure and temperature sensors. In addition, unique oil and water inflow tracers were installed to enable monitoring without intervention risks, with limited personnel and costs. The sensors were strategically placed near the junctions in the mother-bore. The primary objective was to conduct a blind comparison of inflow tracing and conventional production logging, assessing tracer applicability in a complex well and reservoir environment. The chosen well, a penta-lateral with extended reach, completed across multiple zones with different pressure regimes and high H2S, provided a challenging setting for this comparison. The study implemented monitoring campaigns under varied rate conditions, with and without PLT, to evaluate the downhole technologies’ performance. This paper presents novel and patented modeling methods designed to accurately interpret inflow tracer responses, especially where standard modelling approaches fall short. The blind comparison initiative, encompassing six distinct monitoring campaigns across different production scenarios in a carbonate oil reservoir, aimed to track lateral performance over time. The findings indicate that inflow tracer interpretations are comparably similar to PLT results, validating tracer methodology as a means to enhance and simplify well monitoring in complex well settings.