Year
2018
Abstract
Signals recorded in the very near field (few 100s m) of industrial environments display a mixture of multiple harmonic signals with corresponding overtones embedded in broad band noise (tonal noise). Tonal noise is usually related to the operation of machinery with rotating elements (e.g.: pumps and fans). Broadband noise is the result of the vibrations of the structures and the subsequent fluid displacement. The characterization and evolution of the near-field seismo-acoustic wavefield of such facilities can provide a tool to monitor the different subaerial and underground operations and thus have a potential for geophysical monitoring of plant operations. We have deployed a permanent seismo-acoustic station near the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. We performed analysis of the continuous seismo-acoustic data gathered by applying an energy-change detector that is able to identify small changes in the frequency distribution of elastic energy. Preliminary results show correlation between these events with facility operations.