Geophones have been the motion sensor of choice in oil and gas exploration surveys for many years and for good reason: they require no electrical power to operate, are lightweight, robust, and able to detect extremely small ground displacements. However, the seismic industry recently has developed considerable interest in microelectro mechanical systems (MEMS) accelerometers, which are similar to those used to sense accelerations for airbag deployment and missile guidance (among many other uses). The MEMS element is tied to an application specific integrated circuit (ASIC) that includes sensor signal conditioning, feedback control, and digitization blocks. The result is a custom-built unit for seismic applications that requires a power supply to operate.

You do not currently have access to this article.