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Stephen Pharez, Petroleum Geo-Services (United Kingdom)
David Carlson, Petroleum Geo-Services (United States)
Walter Söllner, Petroleum Geo-Services (Norway)
Anthony Day, Petroleum Geo-Services (Norway)
Martin Widmaier, Petroleum Geo-Services (Norway)
Guillaume Cambois, Petroleum Geo-Services (Norway)
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Traditionally, towed marine cables measure the seismic wavefield using only hydrophones. A new solid core dual-sensor cable has been introduced that measures simultaneously the pressure using hydrophones and the vertical component of the particle velocity using motion sensors. The two wavefield measurements are made at the same locations in a single streamer, which facilitates the data acquisition. The first of many advantages of measuring the dual wavefield is that the two measures can be combined to separate the wavefield into up-going and down-going components. This method may be used to derive the up-going pressure field, thereby eliminating the receiver ghost. This gives increased bandwidth for both low and high frequencies, which consequently enhances resolution and signal penetration. Another advantage, and the reason for the added low frequencies, is that, since the receiver ghost can be suppressed, the streamer can be towed at greater depth where it encounters reduced acquisition noise thus improving the ability to acquire data during rough weather. The up- and down-going wavefields can be extrapolated and summed to reconstruct the total wavefield at any recording depth. The ability to separate wavefields is also advantageous for suppressing surface related multiples. These applications are illustrated using 2-D field test data that was acquired concurrently with a survey that used a standard (hydrophone only) cable.
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