Multi-bandwidth Blending, the Future of Seismic Acquisition?

Abstract

In traditional seismic surveys a single source (array) is used for each shot record. Therefore, it must transmit the full temporal frequency band. For example, a seismic vibrator and an airgun array are designed such that they have a large bandwidth. In general it is difficult and expensive to produce wideband sources. In addition, such designs are often a compromise. In blended acquisition, more sources are used than in a traditional acquisition. We propose that the individual sources do not need to satisfy the same strong wide-band requirements. Instead, they may be limited-bandwidth designs, which are simpler, less expensive and easier to control. With a multitude of narrow-band source elements, the blended incident wavefield at a particular subsurface gridpoint will contain the full temporal bandwidth. Because of the continuous growth in the number of sources and the number of recording channels, we expect that the future seismic acquisition will be robotized. In practice this means small autonomous source boats with single airguns of different sizes (marine) and autonomous single vibrators of different sizes (on land).