Equinor plans to deploy cabled subsea instrumentation from Sonardyne International to help increase the accuracy of time-lapse seismic data at the Johan Sverdrup oil field.
From first production at the development, Equinor plans to use seafloor based seismic cable permanent reservoir monitoring (PRM) technology to observe what is happening in the reservoir over time to help maximize recovery rates.
Equinor has engaged subsea services contractor Subsea 7 to install a Sonardyne Pressure Inverted Echo Sounder (PIES) at 110 – 120 meter water depth at Johan Sverdrup.
PIES instruments continuously measure the two-way travel time of sound waves propagated through the water column from the seabed to the sea surface as well as the pressure (depth) at the seabed. This data is then used to calculate a continuous time history of average water velocity and tidal variation throughout the whole water column.
This will be only the second time where PIES units are hardwired into topside power and communication infrastructure, which means Equinor will have instant and continuous access to their data, the company explained.
Conventionally, PIES data is collected acoustically by a passing surface vessel, including unmanned surface vessels.
Shaun Dunn, global business manager for Exploration and Surveillance at Sonardyne, said, “Time-lapse seismic is a key tool to help operators optimize their recovery rates through improved reservoir visualization, modelling and eventually also predictive analytics. By using a PIES, Equinor will have higher repeatability in their seismic data which further supports proactive reservoir management.”