Method of making a marine seismic streamer

Abstract

A seismic streamer comprises a substantially solid core having many of the main components of the streamer, namely hydrophones, electronics modules for digitising the outputs of the hydrophones, the main optical and electrical conductor bundles and Keviar strength members, embedded in it. The core also contains a large number of foam buoyancy elements. An outer skin surrounds the core, defining an annular gap around the core, and this annular gap is filled with open-celled polyurethane foam saturated with kerosene. The capsules containing the hydrophones communicate with the annular gap around the core, so that the kerosene can enter the capsules, each of which contains an open-celled polyurethane foam sheath to cushion the hydrophone. In an alternative construction, made possible by using the buoyancy elements in the core to render the core approximately neutrally buoyant in water, the outer skin and the polyurethane foam are omitted, and the core is used on its own as a solid streamer.