Current and future multicomponent towed streamer design

Abstract

Summary The towed streamer market is moving towards the widespread use of multicomponent streamers. This type of streamer contains hydrophones and particle motion sensors which are used to carry out receiver-side deghosting of the data. The main source of noise on the particle motion sensors is streamer transverse vibration, and it can be challenging to obtain a high enough signal to noise ratio to use this data in the de-ghosting process. In this paper, we study how the characteristics of transverse vibration noise are affected by the choice of the streamer mechanical platform. To compare the implications of design options we built different streamer sections with dense single sensor sampling, identical electronic backbones and MEMS sensors. We towed them together under different tensions in a field experiment and observed that, as expected, the transverse vibration noise was the dominant noise mode, with dispersion characteristics depending on the streamer bending stiffness. We also found that the noise amplitude and maximum frequency (under the same towing conditions) depends on the mechanical properties of the cable, and that they could be reduced by using a new type of gel optimized to dampen vibration. As a result of theoretical modelling and these field observations we propose a new approach to streamer noise attenuation which involves optimising the mechanical characteristics and using non-uniform single sensor sampling in the design of the cable. This avoids some of the compromises we incur using analog arrays and the high cost of single sensor, uniform Nyquist sampling.