Research and Application of Downhole Pressure Monitoring for Identifying Fracture-Driven Interference

Abstract Downhole pressure monitoring technology, recognized for its operational simplicity and cost-effectiveness, provides critical insights for evaluating fracture communication and optimizing fracturing parameters. This technology is implemented through two main approaches: in-well monitoring for assessing inter-stage communication and offset-well monitoring for diagnosing inter-well fracture connectivity, with its core methodology centered on the interpretation of pressure and temperature curve characteristics. This study establishes a systematic classification of pressure responses through comprehensive field monitoring data analysis. By integrating fracture diagnostics with numerical simulations, a standardized interpretation framework has been developed. For in-well monitoring, four distinct response types are identified: no communication, minor leakage due to cementing issues, minor communication from stage spacing, and severe fracture hits. Notably, minor fracture interference indicates effective inter-stage coverage and benefits stimulation, while severe fracture hits negatively impact production. Key influencing factors include stage spacing, natural fractures, cementing quality, and operational continuity. In offset-well monitoring, pressure responses are categorized into poroelastic effects, pressure diffusion, direct communication, and no response. Only direct communication adversely affects production, while the other responses indicate favorable fracture development. The successful implementation of this methodology across multiple field blocks has reduced inter-stage communication probability from 15.1% to 7.4%, demonstrating its significant practical value for optimizing fracturing design and enhancing operational efficiency.