Recent advances in MEMS have facilitated measurement of very weak signals transmitted through soil from low frequency excitation of pipelines. The newest experimental MEMS seismometers with noise floors as low as 10 ng/√Hz and frequency bandwidths from 0.1 to 100 Hz, promise a new method to compensate for the deficiencies in today’s leak detection methods.
The in-situ setup is a passive leak detection method according to which a two-layer network of seismometers is used to monitor the pipeline. The first and second layers of sensors act respectively as inputs and outputs to the system. The propagation medium (soil) between the sensors, through which pipeline energy dissipates, is defined in this research as the “signal channel”. An experimental setup comprised of mechanical hardware, instrumentation and software for signal acquisition and analysis, is used to investigate the feasibility of the approach. Minute changes of the transfer function, due to product contamination, are revealed in the dynamic mechanical properties of the signal channel.