Two of the main limiting factors in seismic resolution for marine towed-streamer acquisition are the ghost effect and sparsecrossline sampling of the streamers. The ghost is the reflection from the sea surface that interferes constructively ordestructively with the primary reflections, reducing the seismic bandwidth at the low and high ends of the spectrum.Acquisition and processing solutions to address the receiver ghost problem were introduced in early 1980s and again in the lastfive years; these are:1 Slant streamer (Ray and Moore, 1982)2 Over/under streamers (S?nneland, et al., 1986)3 Hydrophone-vertical geophone streamers (Carlson, et al., 2007)4 Variable receiver depth acquisition and processing (Soubaras, 2010; Moldoveanu, et al., 2012)These solutions address only the temporal resolution by attenuating the receiver notch. A new towed-streamer technologybased on multimeasurement acquisition was introduced in 2012 that addresses both temporal and spatial resolution.The concept of multimeasurement towed streamers was introduced by Robertsson et al. (2008). The system measures pressurewith hydrophones and particle acceleration in crossline and vertical directions with accelerometers. As the pressure gradientcan be derived from acceleration, the multimeasurement streamers provide measurements of pressure and gradient of pressurein two directions. Based on these measurements, wavefield separation of upgoing and downgoing components can beperformed simultaneously with crossline wavefield reconstruction (?zbek et al., 2010). The multimeasurement system enablesone to calculate the 3D upgoing wavefield at any desired position within the spread, for instance, a densely sampled grid of6.25 m x 6.25 m, and this allows improving not only the temporal bandwidth, but also the spatial bandwidth. Multisensorstreamers can be deployed at larger depths and this improves low-frequency content, signal-to-noise ratio due to reduced swellnoise, and acquisition efficiency. Operational efficiency can be further improved by using multimeasurement towed-streamerdata to detect and eliminate seismic interferences (Vassallo et al., 2012). Seismic modeling and feasibility studies wereconducted to prove that this new marine acquisition technology performs as expected, and commercial seismic surveying hasalready been performed with the new system.
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