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Changing the PRM

Whichever it is, the onus has fallen on the service sector to come up with a winning solution. As with much technology advance in the seismic business, oil companies have been

Production able to sit back and wait to see what is on offer.

Ironically, the major marine seis- mic contractors have not fallen over themselves to win this particular technology race because it is not a great value proposition for them.

Supplying equipment and installing a PRM system is a one-off project, while the margins to be made in equipment maintenance, reshoots, value and even the regular data processing are not that enticing. There needs to proposition be a stream of coming projects for the business to make commercial project on the Valhall feld, off sense. It is perhaps symptomatic that

Andrew McBarnet suggests

Norway. UK-based WGP Group has Schlumberger, which was involved that seismic permanent been carrying out two monitoring in the very frst pioneering PRM reservoir monitoring may surveys each year, using a portable system, on the Foinaven feld west modular source system (PMSS) that of Shetland in the late 1990s, has soon be seeing a new wave it designed. Not so long ago, the not been involved in advancing this of interest if not an increase company reported the 15th reshoot technology. The company apparently in projects.

over Valhall. Over the years, there does not regard it as a sustainable have been numerous testimonials business. This has not stopped major from BP to the technical success and geophysical companies such as

It seems like forever that people in economic value of LoFS in help- Petroleum GeoServices (PGS), CGG, the E&P business have been talking ing to boost production from a feld and TGS from investing in seismic about a digital oilfeld in which seis- expected to continue until 2050. The PRM technology solutions.

mic permanent reservoir monitoring apparent value of LoFS encouraged Marine seismic contractors do (PRM) would play an integral part. BP to undertake further PRM-type understand the value of 4D seismic

Ever since 3D time-lapse seismic, or installations on the Clair feld in the to offshore oilfeld operators. Up to 4D seismic, was shown to work, in UK offshore sector and on the Azeri- now, they have successfully persuad- the 1980s, the potential value of hav- Chirag-Gunashli (ACG) complex in ed the industry that towed-streamer, ing seismic recording instruments the Caspian Sea. repeat 3D, high-resolution seismic placed on the seabed for the lifetime Not surprisingly, the BP experi- surveys over a reservoir target can of a feld seemed so logical as to ence fueled an expectation in the provide a satisfactory monitoring be irresistible for optimal reservoir E&P seismic community of new busi- solution at a fraction of the cost and management. Once a system is in- ness. But PRM has attracted so few risk of a PRM survey installation, or stalled, regular, more or less exactly takers in the last decade that it could even an ocean-bottom seismic survey repeatable, seismic surveys can be just as well stand for Phantom Reser- using retrievable cables or nodes. shot at the minimal cost of a vessel voir Market. Excluding the BP felds, The towed-streamer results cannot with an airgun and some instru- the tally for PRM projects, either compete with the improved imag- mentation. The result should offer announced or in service, amounts to ing from multi-component seismic valuable images of the changes in Ekofsk in Norway (ConcoPhillips); recording on the seafoor. Only a a reservoir’s character as a result of Jubarte in Brazil (Petrobras); BC-10 few companies, with the fnancial ca- hydrocarbon extraction, and provide in Brazil (Shell), Snorre, and Grane pability and technical competence to data to determine the best oil and gas (Statoil). Not exactly a boom. make full use of that data, will order depletion strategy. Oil-company pushback regarding ocean bottom 4D, but they are very

As we know, things haven’t turned the adoption of seismic PRM has much in the minority. out quite as expected. It is now 10 either been on technical grounds, the But any type of 4D seismic can years since BP began operations with value proposition or, whether such scarcely be called mainstream. For the frst life- of-feld seismic (LoFS) a system is appropriate or necessary. example, this year offshore UK and

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