Integrated Geomechanics Study to Mitigate Compaction Well Operability Limit Risks in Condensate and Gas Field Development

ABSTRACT: An integrated geomechanics study is presented to determine compaction well operability limit (CWOL) crucial to depletion planning in condensate and gas fields. CWOL represents the reservoir depletion limit at a specific drawdown for preventing wellbore failure due to reservoir compaction. Objectives include understanding key geoscience drivers for geomechanics data associated with CWOL, reducing uncertainty in geomechanics data inputs for CWOL assessment, and filling data gaps in regions without geomechanics data. A comprehensive geomechanics database was compiled, quality-checked, and combined with key geoscience data for the region. The database includes compressibility from uniaxial-strain (UXS) compressibility testing, depletion pressure at onset of pore collapse (UXS), Routine Core Analysis (RCAL), X-ray Diffraction (XRD), Reservoir Quality (RQ), particle size analysis (PSA), and core description information. By applying integrated data analysis and machine learning to the database, the most essential controlling factors impacting CWOL have been determined. A fundamental framework was established to substantially reduce the uncertainty ranges of CWOL for the target reservoirs, thereby providing greater confidence in depletion planning. Finally, core- and log-data based predictive models were successfully developed using supervised machine learning for entire-field CWOL prediction, enabling screening of reservoirs sensitive to depletion (low CWOL), especially for the regions lacking geomechanics information.