Characterization of Annular Cement Permeability of a Logged Well Section Using Pressure–Pulse Decay Measurements

Abstract The cement behind casings is an important barrier element in wells that should provide zonal isolation along the well. hardened does not always isolate permeable formations, either due to placement issues or loads over time compromise integrity of barrier. modern method used characterize annular material ultrasonic logging which provides essential information concerning type casing, but no measurement permeability. This study permeability characterization a casing-cement sandwich joint retrieved from 33 years old production well has been logged at surface using state-of-the-art tool. contains interval low-permeable previously prevented by gas injection. A pressure–pulse decay test now performed based on monitoring evolution pressure pulse through joint. Long-term measurements show communication entire and are qualitative agreement with log. diffusion model estimate local joint, enabling comparison log response region relatively short, situated directly top casing collar, orders magnitude lower than above below. In longer term, results this related studies can be as input for future sustained evaluations quantifying seepage risk abandonment designs.