Reservoir monitoring surveys using gWatch at several Equinor-operated gas fields

Advanced gWatch technology
Location Client Date
North Sea, Norwegian Sea & Barents Sea Equinor Summer 2023

Reach Subsea, offering high-quality solutions and technology to clients in need of ocean data and services, recently announced a notable accomplishment. The company has been awarded a contract encompassing surveying, monitoring, and subsea services, provided as an integrated turn-key solution. This milestone further marks the beginning of a gravity and seafloor deformation survey campaign that covers several Equinor-operated gas fields and is scheduled to commence in July this year.

Operations Engineer Geir Clement Wågen is giving student Hedda Sofie Færøy a training session in operations of the control room, for the upcoming gWatch campaign

Project in brief

  • Monitor survey at the Troll field (Troll East and Troll West)
  • Monitor survey at the Aasta Hansteen field
  • Installation of 35 concrete pads on the Irpa field
  • Monitor survey at the Snøhvit field (including the Snøhvit CO2 injection site)
  • Monitor survey at the Albatross field
  • Installation of 12 concrete pads and monitor survey at the Askeladd field

Fields of Operations

The gravity and seafloor deformation survey campaign encompasses several gas fields under Equinor’s operation. These fields, located in the North Sea, the Norwegian Sea, and the Barents Sea, hold great potential for gas production. By conducting detailed surveys, Reach Subsea will gather data to improve Equinor’s understanding of these fields, optimizing production strategies and maximizing resource extraction

The gWatch Technology 

Reach Subsea’s monitoring division will provide its leading-edge gWatch technology to the project. This advanced gravimetry-based survey method promises to deliver accurate data quality while minimizing the impact on the environment.  It combines advanced compact instrumentation, efficient data collection methods, and sustainable practices to ensure accurate data collection while reducing harm to marine life. The gravimetry technology used by Reach Subsea provides measurements of gravitational variations, offering valuable insights into the subsea bed strata and reservoir characteristics. The combination of Reach Subsea’s expertise and innovative technology sets the stage for visionary survey capabilities.

Vessel and Equipment 

The Viking Reach, Reach Subsea’s newly acquired ROV survey/light construction vessel, will play an important role in the gravimetry survey campaign. Equipped with relevant technology and designed to handle complex underwater operations, the vessel offers a stable and efficient platform for conducting the surveys. For this particular project, the Viking Reach will be mobilized with one SROV (Survey Remotely Operated Vehicle) and one work class ROV. Additionally, hull-mounted survey equipment will be utilized to gather comprehensive data-sets from the underwater environment. This comprehensive setup ensures that the gWatch surveys are performed with precision and accuracy. 

gWatch survey equipment mobilized onboard the Viking Reach

Future Prospects 

The award of this work by Equinor as a call off from the multi scope agreement with Reach Subseahighlights the company’s expanded product offering and the value it provides to clients. The utilization of gravimetry-based surveys as part of an integrated project delivery opens up interesting possibilities for Reach Subsea’s future operations. The compact and cost-efficient equipment employed in this project showcases the potential for using similar technologies with Reach Remote, their remote survey vessel platform. As the industry continues to evolve, Reach Subsea remains at the forefront of technological development, along the route to remote survey project delivery by embracing innovation and driving efficiency in underwater services.

Mobilization of the vessel Viking Reach started Monday 31st of July


Reach Subsea’s collaboration with Equinor for a gravimetry survey campaign at several gas fields in the North Sea, the Norwegian Sea, and the Barents Sea marks an important milestone. By leveraging Reach Subsea’s advanced gWatch technology, Equinor aims to gather high-quality data to optimize production strategies, illustrating the potential advantages that gravimetry surveys may provide through an integrated cost-effective project delivery. As Reach Subsea continues to push the boundaries of underwater services, their dedication to innovation positions them as a key player in the industry.