Implications from Transfer Functions when Comparing Seismic Data from MEMS Accelerometers and Geophones

Summary Digital sensors based on micro electro mechanical systems (MEMS) accelerometers are one of the newest technologies being used in seismic acquisition. As such, there remains some confusion surrounding the similarities and differences relative to the coil-over-magnet geophone. By modeling the transfer functions of these devices and convolving displacement domain wavelets of varying frequency content with them, it will be demonstrated that raw electrical signals output by the sensor elements are expected to be similar in appearance. Also, the dominant frequency of the wavelet relative to the geophone’s resonant frequency determines whether the MEMS accelerometer result is an apparent phase lead or phase lag relative to the geophone result.