DEVELOPMENT OF WOVEN BELT TYPE LAND STREAMER AND ITS APPLICATION TO HIGH-RESOLUTION SEISMIC SURVEY

The Land Streamer developed by the author uses non-stretch woven belt as a towing member but also as a component to mount geophone units in which geophone elements are incorporated. Because the belt is made of textile fabrics, the guided waves through the belt are negligibly small under the nontensioned condition. A metallic baseplate bolted under the belt ensures the coupling of the geophone unit with the ground. This firm fixation of geophone elements in the unit and plane contact of the unit to the surface with the aid of the belt weight brings high quality data comparable to those acquired by planted geophones. The surface condition of the ground is another important factor which strongly affects the data quality in high-resolution seismic survey. Comparative tests revealed the effect of pavement as a high-pass filter, and proved the advantages of the Land Streamer for the high-quality data acquisition at paved areas. One disadvantage of the tool is its prefixed spacing of geophone units or the baseplate. We therefore manufactured various types of belts and sensor units and combined them to meet with the targeting depths and structures of a survey. The tools have been successfully utilized to high-resolution seismic reflection surveys especially in urban areas, where the surface is mostly paved and cultural noises had perturbed the collection of high quality geophysical data.