This project involves four injection-production wells located in a gas storage facility. Each well adopts a three-section drilling design, completed through open-hole casing cementing. The target reservoir lies at an approximate depth of 3000 meters, characterized by low porosity (3.76%–8.61%) and low permeability (0.16–9.67 mD).

During various operational phases, individual wells may encounter well integrity issues, including casing damage, external channeling, and packer seal failure. Such issues can lead to suboptimal daily gas injection and production rates, with potential risks to operational safety.

To address these challenges, our company employs a semi-permanent deployment method, embedding distributed optical fibers along the external surface of the tubing, extending to the target reservoir. By leveraging temperature data collected via distributed fiber optic sensing, combined with our proprietary realtime wellbore integrity monitoring algorithm for gas storage wells, we achieve:
 Continuous Monitoring: Real-time detection of well integrity parameters.
 Early Warning Mechanism: Immediate identification of anomalies, enabling proactive intervention.
 Precision Diagnostics: Accurate localization of integrity issues, pinpointing the depth and time intervals of detected anomalies.
For instance, in Well XX, during the initial shut-in phase, a temperature anomaly was identified at a depth range of 90m–105m, with an initial drop followed by a subsequent rise. The maximum temperature decrease reached 24.62°C. This triggered an automatic well integrity alarm lasting 7.8 hours, ensuring timely issue identification and rapid response measures.

By integrating distributed fiber optic data with geological information, the root cause of the observed well integrity issue was determined. Analysis indicated a minor leak likely occurred near the tubing body or thread at a depth of approximately 102.15m. Based on this diagnosis, a targeted technical solution was proposed, effectively addressing the integrity concern. This innovative approach provides critical technical support for the client, ensuring the safe, efficient, and reliable operation of the gas storage facility