Valhall: Life of Field Seismic
When BP decided to install a permanent ocean bottom cable over the Valhall field in the North Sea, the objective was to deliver high quality 4D images of the reservoir every three months, and monitor the movement of fluids within the reservoir.
In order to achieve this goal it was essential that the source signature was just as repeatable as the instrument response of the receivers. BP selected DigiSHOT to provide digital source control for the source.
To reduce acquisition costs, BP selected the Ocean Flower (a Rovde support vessel) as the source vessel. Safety issues associated with a dual-use vessel prompted BP to utilize a unique rapid retrieval and deployment system, which required ION to modify the original DigiSHOT design.
DigiSHOT has delivered. The repeatability of the data is the best ever achieved. The data example shown here shows the variation in injection rates along a horizontal injection well. BP has also published widely commercial success of the project, claiming an increase in production of up to 60 million barrels(1).
(1) “Seismic on demand for BP’s born-again Valhall field”,
Oil Online, July 11, 2003
