Abstract: This invention describes an apparatus and method for generating seismic waves in the earth for seismic geophysical prospecting. It involves a slender pipe open at the lower end, which can be driven into the earth to a shallow depth. The upper end is closed. Means are provided for introducing oxygen and acetylene through a pair of control valves and check valves, for a selected period of time. The oxygen and acetylene are mixed in the pipe and flow downward through the pipe and through the perforations into the earth, and fill the voids and fissures in the shallow sediments. Means are provided in the top end of the pipe to detonate the gas mixture. The detonation wave travels down the pipe and eventually reaches the openings at the lower end, and detonates the gas in the pores and fissures of the earth. The resulting explosion opens up the fissures and provides a larger void space than was there before.