| Experiments were conducted in order to reduce the acquisition time of three-dimensional (3-D) seismic reflection surveys. Steel square-tubing was used as the material to which the geophones were rigidly mounted as previous research determined the square tubing was superior to various shapes and media. The initial two-dimensional (2-D) array was efficiently transported and planted, and recorded useful seismic information (reflections as well as refracted and surface waves). Unfortunately, the array also recorded strong reverberations and anomalous modes associated with the body waves. The rigidity of the array in two dimensions caused it to flex or vibrate in response to incoming seismic energy. The reverberations degraded the quality of the data and the array was determined ineffective for near-surface seismic imaging.; To solve the reverberation problem, the level of interaction between the geophones and steel planting material was reduced. Experiments involved channel-iron modified with compression springs and square tubing with holes drilled into it. (Abstract shortened by UMI.)... |
