Prediction of lost circulation risk in fractured formations based on 3D geomechanical modeling

• An improved 3D geomechanical modeling method integrates multi-source data and three LC-related sensitivity factors (fracture characteristics, rock brittleness, in-situ stress) for pre-drilling lost circulation risk prediction. • A quantitative risk assessment model combines the analytic hierarchy process (AHP) and entropy weight method (EWM) to assign weights, overcoming limitations of arbitrary factor selection and subjective weighting. • The model enables digital visualization of regional risk zones, validated against field-identified LC zones with an average relative error of 19.08%, confirming its reliability. • The method provides practical guidance for mitigating lost circulation risks and optimizing drilling program designs in fractured formations.