oa Hydraulic Fracture Production Monitoring Using Hybrid Distributed Acoustic-Temperature Sensing Based on Ultra-Weak Fiber Bragg Gratings

Fiber optic technology possesses inherent characteristics, including compact size, exceptional temperature and pressure resistance, corrosion resistance, minimal optical loss, immunity to electromagnetic interference, and absence of hysteresis. These unique qualities make optical fiber an unparalleled choice for borehole monitoring. Over the past few years, distributed fiber optic sensing has emerged as a valuable tool for monitoring oil and gas production, offering versatility regardless of the complexities of geometry and completion. In particular, Distributed Acoustic Sensing (DAS) and Distributed Temperature Sensing (DTS) techniques have gained significant traction in hydraulic fracturing of unconventional reservoirs, surpassing the capabilities of traditional seismic technology.

In our study, we present the integration of DAS and DTS techniques within a groundbreaking and cost-effective system known as DXS. To achieve hydraulic fracturing production monitoring, we utilize a fiber optic cable installed outside the casing, incorporating an ultra-weak fiber Bragg grating array. Through a comprehensive field test, we demonstrate the practical implementation of this system. Additionally, we conduct a comparative analysis by juxtaposing the real-time monitoring data collected by the DXS system with that of a commercial DAS/DTS system.