A semi-analytical approach to model drilling fluid leakage into fractured formation

Loss of circulation while drilling is a challenging problem that may interrupt operations, reduce efficiency, and contaminate the subsurface. When drilled borehole intercepts conductive faults or fractures, lost manifests as partial total escape drilling, workover, cementing fluids, into surrounding rock formations. control materials (LCM) are often used in mitigation process. Understanding fracture effective hydraulic properties fluid leakage behavior crucial to mitigate this problem. Analytical modeling flow fractures tool can be quickly deployed assess perform diagnostics, including rate decline, conductivity, selection LCM. Such models should applicable Newtonian non-Newtonian yield-stress where rheology nonlinear function shear stress. In work, new semi-analytical solution developed model fractured medium. The for various types exhibiting yield-power-law (Herschel-Bulkley). We use high-resolution finite-element simulations based on Cauchy equation verify our solutions. also generate type-curves compare them others literature. demonstrate applicability proposed two field cases encountering circulations. To address subsurface uncertainty, we combine solutions with Monte-Carlo probabilistic predictions. method estimate range parametrized by aperture, time-dependent loss predict cumulative volume fluid. approach accurate efficient enough support decision-making real-time operations.