f The 'Shock Gun' - a Revolutionary New Seismic Source Based on 'Shock Tube' Technology

British Gas Research and Technology has developed a novel seismic source based on 'shock tube' technology (Melvin & Clarke, in press). A high pressure gas (typically with a low density and high sound velocity) is initially separated from a second low pressure gas (higher density and lower sound velocity). The gases are separated by a rapidly opening valve or bursting disc. When this barrier is removed the high pressure gas impacts on the low pressure gas and a shock wave develops.