Application of MEMS accelerometer to geophysics

Abstract

We developed several types of MEMS accelerometers using commercial MEMS elements for trial use in seismic surveys. Field experiments and earthquake observations were carried out for investigating the capabilities of the MEMS accelerometers. The results of these experiments and observations show that the properties of these MEMS accelerometers are similar and that they are about 1.5-3.0 times as sensitive as conventional geophones used in seismic surveys. The noise level of the MEMS 3-C accelerometer in natural earthquake observation was about 10-4kine (cm/s), and the useable frequency band extends to below 1Hz. For future works, we will further investigate the characteristic of MEMS geophones in low frequency band using earthquake records. In addition, we will reexamine the electronic circuit and the MEMS elements in order to attain high sensitivity.