Mapping Water Paths Using Ultra-High Resolution Borehole Imaging and Ultra-Deep Directional Resistivity Logging While Drilling in Carbonate Reservoirs

Abstract Water production is one of the most prevalent challenges for oil producers in water-flooded reservoirs. In carbonate reservoirs, this issue is exacerbated by the abundance of fractures and faults, which can create complex water-flow pathways when connected to aquifers or nearby water injectors. This paper explores technologies that help with understanding the relationship between fractures and water movement in such reservoirs. The recent development of the ultra-deep resistivity-based 3D reservoir mapping tool has opened the possibility of 360-degree reservoir mapping, extending over 150 feet away from the wellbore. Given the natural resistivity contrast between water and hydrocarbon-bearing formations, this tool is particularly effective in distinguishing water from hydrocarbons and mapping oil-water contacts (OWC). Improvements in resolution through 2D transverse inversion processing, which offers fine resolution in the plane perpendicular to the wellbore, have enabled the identification of irregular features, such as water-fronts or water-flow paths near the wellbore. Additionally, advancements in near-wellbore imaging technology have enhanced borehole imaging resolution to 0.2 inches. The resistivity-based ultra-high-resolution imaging tools can now capture features like faults and fractures while also distinguishing between conductive and resistive fractures. By integrating high-resolution near-wellbore imaging with deep-reading reservoir-scale mapping, a comprehensive approach to understand OWC, irregular water-fronts, and potential water pathways near production wells is achieved. This paper presents the results from two recent wells where this combination of technologies was applied, highlighting the value of this integration for optimizing completions and ultimately improving production. Having access to such detailed information during the drilling of production wells enabled proactive measures to optimize completion strategies, effectively delaying or even preventing water production. The ultra-deep azimuthal resistivity tool provided full 3D mapping of the area around the wellbore, revealing water movement controlled by fractures identified using the ultra-high-resolution image resistivity imaging tool. The multiscale, multidiscipline, and multidimensional integration of logging-while-drilling (LWD) measurements revealed complex water corridors linked to fractures and faults in carbonate reservoirs. This enhanced understanding of water movement within the reservoir marks a new level of insight. Incorporating this knowledge into reservoir models will be critical for future digitalization and automation of reservoir management practices.