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3.5 Km/Day Of High Resolution Seismic Reflection Data Using A Landstreamer1
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 17th EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, Feb 2004, cp-186-00119
Abstract
The Illinois State Geological Survey has undertaken the task of preparing 3D quadrangle maps of<br>the upper 100 meters of the entire state at a scale of 1:24,000. High resolution seismic reflection<br>techniques have provided vital data for constructing realistic maps and cross sections. At first,<br>conventional seismic acquisition methods were used. We used a 48-channel system with 3 m shot spacing<br>and geophones planted geophones in the ground with 3 m spacing. A crew of 6-8 people achieved an<br>acquisition rate of up to 2 km/day. In the context of the mapping program, this crew size was too<br>expensive relative to the amount of data acquired. To improve our acquisition rate, we designed a 24-<br>channel landstreamer system that uses a crew of 3 to 5 people. With a shot spacing of 3 m, we can acquire<br>data at a rate of up to 3.5 km/day. We use an automatic weight-dropper mounted on an ATV or a trailer,<br>and a high-precision distance measuring device to reduce our shot cycle to 10 or 15 seconds. Now, the<br>major challenge is to cool the motor driving the hydraulic system of the weight dropper.