Maersk Oil Qatar has, in cooperation with Qatar Petroleum, recently completed the world's largest ultra-high resolution 3-D seismic survey over the Al Shaheen field offshore Qatar. Acquisition started in October 2006 using the PGS vessel Pacific Explorer in an eight-streamer configuration.


The seismic survey is part of a development plan that will increase the Al Shaheen Field production to a plateau level of 525,000 barrels/day from late 2009. The 2005 Field Development Plan comprises drilling of more than 160 additional production and water injection wells as well as establishment of three additional offshore platform locations with production and accommodation facilities.


The seismic survey has been designed specifically for high-resolution imaging of relatively shallow targets. Narrow streamer separation allows for high lateral resolution of structural and stratigraphic features, while shallow streamer and source depths of 4.5m and 4m, respectively, offer a highbandwidth signal for vertical resolution of thin beds in the subsurface.


The sail lines were obstructed with both Maersk Oil Qatar and other operator’s oilfield installations, making the survey a logistical as well as a geophysical challenge. The survey area contained as much as 47 installations, and nearly 300 “close passes” were needed to obtain maximum data coverage. In addition, other seismic surveys were ongoing in the area which needed to be included in the day-to-day operational planning.


PGS and Maersk Oil Qatar were aided by a novel online graphic survey progress and planning tool. This system supplies updated vessel data, support vessel positions, positions of other seismic vessels in the areaand survey progress data approximately every hour online to both Maersk Oil Qatar and PGS offices. In this way, both companies were able to collaborate effectively to plan and manage the survey in the most productive manner. This project was the first full implementation of the planning system, and several new features were implemented in the functionality of the system during the course of the survey.


President of PGS Marine Rune Eng commented, "We are very pleased to be associated with Maersk Oil on this survey. These kinds of configurations are a key part of our HD3D survey suite -- leveraging the experience of our offshore crews and the precise control of In-sea equipment in these very dense spreads to create clearer images for our customers. I'm also happy to report no Lost Time Incidents or spills during the execution of this substantial and innovative program."


Officials from Maersk Oil Qatar commented, “We would like to thank QP and the external operators around the Al Shaheen field for excellent assistance and logistical support during the last 10 months. This allowed us to acquire successfully a uniform ultra high-resolution dataset over Block 5 and the Extension Area in a safe manner.”

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