On-Demand Ocean Bottom Node (OD OBN) Technology for Seismic Reservoir Monitoring

Abstract Objective and Scope The objective of On-Demand Ocean Bottom Node (OD OBN) technology is to transform offshore seismic reservoir monitoring by offering a scalable, low-cost, and autonomous solution for long-term data acquisition. OD OBN systems are designed to remain on the seabed for extended periods, enabling continuous monitoring of seismic activity and seabed deformation in deepwater environments. These systems aim to enhance subsurface imaging and reservoir management while minimizing operational footprint and maximizing data quality. Methods, Procedures, Process OD OBN systems utilize modular nodes equipped with seismic sensors, pressure gauges, and inclinometers. Data is autonomously recorded and retrieved via optical laser communications using autonomous underwater vehicles (AUVs). The nodes support both optical and acoustic communication protocols, allowing for health checks and data alignment without human intervention. Deployment strategies include pilot arrays of hundreds of nodes, strategically placed to monitor subsidence and reservoir changes over time. The modular design supports long-term deployment and scalability for various offshore applications. Results, Observations, Conclusions Field trials conducted in deepwater environments demonstrated successful data acquisition and retrieval using OD OBNs. The system showed high repeatability and reliability in capturing time-lapse seismic data, which is essential for managing complex reservoirs. Integration of OD OBNs into reservoir monitoring workflows has the potential to reduce operational footprint and improve data quality. These results validate the feasibility of semi-permanent seabed monitoring and highlight the potential for frequent and flexible seismic surveys. Novel/Additive Information OD OBN technology introduces a paradigm shift in offshore seismic monitoring by combining long-term deployment capability with autonomous data handling. The use of AUVs and optical modems for high-bandwidth communication represents a significant advancement over traditional OBN systems. This approach enables active and passive monitoring and supports adaptive survey planning. The success of OD OBN systems underscores the importance of automation, scalability, and cost-efficiency in future offshore reservoir management strategies. Acknowledgments The authors would like to thank Shell, Petrobras and Senai Cimatec for their kind support making the 4D OD OBN system a reality and supporting the submission of this abstract. Special thanks to Samantha Grandi (Shell), Jorge Lopez (Shell), Alexandre Augusto Cardoso da Silva (Petrobras) Valter Beal (Seani Cimatec).