Five years of experience with landstreamer vibroseis and comparison with conventional seismic data acquisition

Inspired by the work of others and increasing demands in Denmark for new and deeper groundwater resources as well as very costly shallow onshore reflection seismic surveys, we started building a landstreamer for reflection seismic data acquisition in 2000. Since the first 75 m, 30 channel prototype used for testing of the method an ongoing development of the design has taken place. The first landstreamer used for production was 150 m with 60 channels while the current generation has 102 channels, differentiated geophone spacing and a total length of 220 m. All generations of landstreamers have been equipped with conventional geophones mounted on steel sledges and the energy source is an IVI T7000 Minivib seismic vibrator. Examples are shown to illustrate the improvements in data quality along with the ongoing development of the landstreamer setup as well as a direct comparison to both explosive and vibroseis data acquired with conventional geophones and cables. Comparison is also made of frequency spectra from landstreamer mounted and spike geophones planted in the ground. In the past five years we have acquired more than 450 km of seismic using landstreamers and the purposes of the investigations have been multiple: delineation of buried valleys, stratigraphic mapping of deep regional aquifers, faults, geothermal energy projects and mapping of fracture zones in crystalline bedrock. The landstreamer setup has provided a very high production rate and a very high data quality fully comparable to data recorded with a conventional setup.