Abstract: Self-noise level is one of the most important parameters of seismometers. So, how to lower down the self-noise level is a big issue in the design of seismometers. This paper introduces how the two major noise sources-Brownian noise and electronic noise (1/f noise)affect seismometer's self-noise level and transfer function. We analyzed base noise of seismic station recorded by three different kinds of seismometers and study how the self-noise affects the data recorded.

Key words: Seismometer, Brown movement, Electronic noise, Thermal noise, Station base Noise, Noise power spectrum