The 3D Autojuggie: automating acquisition of 3D near‐surface seismic reflection data

Abstract

New instrumentation, known as the 3D Autojuggie, has been developed that allows acquisition of three‐dimensional shallow seismic reflection data in a cost‐effective manner. The 3D Autojuggie is capable of simultaneously planting 220 geophones with 0.5‐m spacing in the inline and crossline directions in less than 1 minute. Likewise, all 220 geophones can be picked up in the same amount of time so that the receiver grid can be moved and redeployed on the order of a few minutes without disconnecting cables and seismographs. This significantly reduces the time required to roll geo‐phones and cables and the number of crew members needed for three‐dimensional high‐resolution seismic surveying. While efficiency of three‐dimensional surveying is demonstrated here, the use of the Autojuggie will be limited in rough terrain and in dry or rocky top soil. This study presents two field tests of the 3D Autojuggie. The first one was conducted over soil using conventional geophones with spikes, and the second one was conducted over hard pavement using geophones mounted on base plates. Each dataset is compared to corresponding walkaway lines of conventional manually placed control geophones. Data acquired using the 3D Autojuggie are directly comparable and nearly indistinguishable to hand‐planted geophones. Field experiments resulted in a minimum of triple the acquisition efficiency increase compared with conventional geophone deployment methods. This work demonstrates that the 3D Autojuggie can facilitate the acquisition of high‐resolution three‐dimensional seismic data, making possible routine ultra‐shallow seismic imaging.