Norwegian oil major Equinor will deploy Sonardyne’s cabled subsea instrumentation to help increase the accuracy of time-lapse seismic data at the Johan Sverdrup oil field offshore Norway.
Sonardyne said on Tuesday that Equinor would use seafloor based seismic cable permanent reservoir monitoring (PRM) technology to observe the reservoir over time to help maximize recovery rates from first production onwards.
While PRM technologies increase the amount and quality of data that operators have about their reservoirs, processing it can be complicated due to environmental conditions such as water velocity and tidal height. If those conditions are known, their impact can be removed.
To resolve this issue, Equinor engaged subsea services contractor Subsea 7 to install a Sonardyne pressure inverted echo sounder (PIES) at 110 – 120-metre 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. Data is then used to calculate a continuous time history of average water velocity and tidal variation throughout the whole water column.
While PIES instruments are already very widely used in marine seismic survey operations, 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.
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, modeling and eventually also predictive analytics. By using PIES, Equinor will have higher repeatability in their seismic data which further supports proactive reservoir management.”
It is worth reminding that the Boka Vanguard (ex. Dockwise Vanguard), the world’s largest heavy lift, and transportation vessel reached Norway earlier this month after a two-month journey from South Korea, carrying the Johan Sverdrup field processing platform topside.