Dynamic Characterization of Post-Fracturing Production Profiles in Horizontal Wells Using Fiber-Optic Monitoring: A Case Study from a Northern China Oilfield

Abstract Dynamic monitoring of production profiles in hydraulically fractured horizontal wells is critical to reservoir drainage efficiency and enhancing hydrocarbon recovery. Conventional production logging techniques face limitations in cost-effectiveness, temporal resolution, and continuous full-wellbore monitoring, hindering precise evaluation of fracture dynamics and fluid production behavior. This study addresses the unresolved production profile challenges in tight reservoir horizontal wells within a northern China oilfield by employing distributed fiber-optic sensing (DFOS) technology, integrating distributed acoustic sensing (DAS) and distributed temperature sensing (DTS). Through multidimensional data fusion and quantitative inversion, the dynamic fluid distribution under varying production regimes is systematically investigated. Four horizontal wells in the target block were instrumented with high-resolution DFOS systems. Full-wellbore acoustic (DAS) and thermal (DTS) data were comprehensively collected during post-fracturing shut-in regimes (short-term shut-in and staged depressurization) and production transition phases. Advanced signal processing techniques, including noise attenuation, time-frequency analysis, and temperature field modeling, were applied to correlate temperature anomalies with fluid phases and flow velocities. A coupled wellbore-reservoir flow model was developed, and a temperature gradient inversion algorithm for DTS data was implemented to establish a dynamic interpretation model for oil-water two-phase production profiles. Historical production data were utilized for multiparameter calibration and model validation.