The Kietta Start-Up: From Design to Acquisition of a 3D Marine Full-Azimuth, Full-Offset Seismic Survey

Offshore seismic prospecting methods need to adapt to the curent price environment and today the goal is to deliver high-quality data suited to advanced subsurface imaging and reservoir characterization while reducing costs. The main innovation of the method developed by the Kietta start-up relies in the constitution of the receiver array and the way it is operated. The recording spread is composed of a set of cables mean to be stationary in midwater (MSC, midwater stationary cable). Each MSC is physically independent of the others and attached as its two ends to unmanned surface vehicles (RAV, recording autonomous vessels) for tensioning and controlling its position. Each MSC is equiped with hydrophones and three-component geophones to measure both pressure wave and velocity. Hydrophone and geophone signals are combined together to cancel out reflection ghost thus leading to a flat amplitude spectrum regarding to depth. The MSC embeds dynamic ballasts to control the depth at low speed. The operations are supervised form a master vessel that communicates with the RAV swarm through wireless radios. Real-time QC is performed onboard. In this paper, a proof of concept followed by a full-fledged project and a production survey in complex environment are presented.