A Novel Source-Over-Cable Solution To Address The Barents Sea Imaging Challenges
J.E. Lie, V. Danielsen, P.E. Dhelie, R. Sablon, R. Siliqi, C. Grubb, V. Vinje, C.I. Nilsen and R. Soubaras
Event name: Marine Acquisition Workshop 2018
Session: Seismic Source Technology
Publication date: 22 August 2018
Info: Extended abstract, PDF ( 3.21Mb )
Price: € 20
The Barents Sea is an important petroleum province for Norway. Several oil and gas fields have been found and some of them are already in production, such as Snøhvit, Goliat and soon Johan Castberg. However, seismic imaging in the area is problematic. The large Tertiary uplift and erosion of the area has brought rocks with high seismic velocities up shallow and the seabed is often irregular due to iceberg plough marks. Lundin set themselves the challenge of fundamentally improving the seismic imaging across the Barents sea. This resulted in a new way of acquiring seismic data, which was developed through close technical cooperation with CGG. The solution involves two vessels, one streamer vessel and one source vessel towing its sources with a wide crossline separation on top of the seismic spread. A series of modelling, field tests, risk assessments led to the decision of acquiring a full-scale source-over-cables acquisition in the Barents Sea during the summer of 2017. This paper describes the geological and geophysical arguments that led to this new acquisition geometry. It also presents the large scale 2017 seismic acquisition as well as the processing and imaging results from this unique slit-spread marine geometry.