Land streamer for shallow seismic data acquisition: Evaluation of gimbal‐mounted geophones

Abstract

To increase the speed and efficiency of shallow seismic data recording and thereby decrease acquisition costs, the concept of a towed land streamer containing self‐orienting, gimbal‐mounted geophones is being evaluated. Our initial experiments at two locations within Switzerland demonstrate that good coupling with the ground may be achieved when the gimbal‐mounted vertical geophones are contained in heavy (∼1 kg) casings and pulled along a very shallow (2–3 cm deep) furrow. Such a furrow may be created by mounting a heavy wheel on the towing vehicle. Placing the geophones in even heavier casings may provide the necessary good coupling with the ground, negating the need for the furrow. Shot gathers and stacked sections recorded with the gimbal‐mounted geophones are practically indistinguishable from those recorded with conventional spike geophones. The principal advantage of this approach is that significantly fewer field personnel (only two or three) are required than for conventional shallow seismic surveying. When fully operational, the new acquisition system should be faster and less expensive for a wide variety of engineering and environmental applications.