'Rig 3D' ? A revolutionary technique looking for a case history

Abstract

Three dimensional (3D) marine seismic surveying is expensive and often a lengthy and technically difficult survey to perform. It is therefore only executed when an economically viable discovery is made. An alternative technique is offered which may be used when a marginally economic discovery is made. The technique is inexpensive compared to the conventional full 3D marine survey; it is cheaper than reconnaissance surveying and two boat operations, and provides a 3D migrated annular volume just over 3 kilometres in diameter for the approximate price of a single offset vertical seismic profile (VSP).The technique uses the exploration drilling rig as the energy source platform, the rig supply vessel as the receiver, and the site location system as the 3D navigation network. In using equipment conventionally mobilized with each drilling rig relocation, costs are substantially reduced and a larger portion of the 3D seismic exploration budget may be transferred to the engineering/drilling budget.Failure of the technique to be trialled is due to the conservatism found within the industry rather than technical considerations.