Array length magnification through the use of multiple sources and receiving arrays

For wide aperture seismic experiments, very long effective arrays can be synthesized by using multiple sources and receiving arrays. In marine seismic work where a source is coincident with the end of each array, the total length of the arrays can be multiplied by a factor between n - 1 and n, where n is the number of sources. Three ships, each with a source and 3.6-km array, can be positioned so that the offset range 0 to 25.2 km can be continuously sampled with duplication only in the 0 to 3.6-km range. With 100-m group spacing these data can be gathered into 252-fold common-depth-point (CDP) data with a CDP spacing of 150 m. While it is not likely that we will ever see five or six ships steaming in line, two and three ships will be used in the near future for detailed sedimentary and deep crustal studies.