Improving Seismic Data By Using Smaller More Compact Seismic Air-Gun Sources

This paper discusses the motivation and development, in the marine seismic industry, to reduce the physical size and the source output energy from a marine seismic air gun source. Generally going down from large multiarray sources to single sub array compact small sources. The idea is to go from using an effective array-source down towards a point-source like output. With the constant desire for ever increasing spatial resolution, it has been deemed necessary to reduce the spatial extent of not just the receivers (from large summed arrays down to single sensor recordings) but also the source. Ideally the source should mimic a singular point source, but as this is practically unachievable, a more compact source of 8x9m (width x length) have been designed, modelled and tested. In addition, both a new compact triple-source as well as several reduced volume sources have been tested, along with an industry first wide-towed dithered hexa-source test. Results from the new compact smaller sources are encouraging and in combination with several smaller autonomous source vessels decoupled from the receivers, the potential for improved imaging through many more sources giving higher spatial density as well as much higher fold is substantial.