Low Frequency Addition to Bubble Gun Seismic Systems
Falmouth Scientific (USA) presented the HMS-620LF low frequency bubble gun seismic system at Oceanology International 2014. Bubble gun systems are suited for small-boat, shallow-water geophysical surveys. The systems utilise a contained air volume to generate narrow-band, low-frequency acoustic signals. The data collected with HMS-620 systems rivals that of much larger, heavier and more expensive air-gun, boomer and sparker systems without the need for large power sources or air compressors.
This proven technology provides superior signal penetration through coarse sand, gravel tills and other difficult-to-penetrate sediments.
With some new technology developments and increases in the physical dimensions of the acoustic transducer FSI can now offer a much lower bandwidth system that gives even deeper signal penetration. Previous bubble gun systems demonstrated frequency characteristics in the low-hundreds of hertz, but the new HMS-620LF shifts the spectrum downward such that it produces substantial energy components below 100Hz. The new system requires a small 2kW generator as its power source.
