Presenter: Chagnon Glynn
Date: 2015/10/08
Abstract
Continuous seismic noise has been recorded on the volcanic island of Tenerife (Canary Island, Spain). Debates surround the origins of the noise and what it means for future risk and hazard management on the island has been ongoing. Much of the noise recorded is highly augmented by anthropogenic noise due to the presence of urban landscapes in proximity of the caldera. However, a previous study (Carniel et al., 2008a) determined that a natural source component is buried by the anthropogenic sources within the seismic noise. This was done by examining the time progression transitions in the dynamical parameters computed on the seismic noise and cross-correlating these transitions with the occurrence of tectonic events. Carniel et al., 2008b, further explored the ‘persistence’ of seismic noise to quantify how much memory it contained of its recent past using the variogram tool. By determining how much history is recorded in the noise can give insight into its future evolution and potentially allow for seismic noise to be used as precursors in volcanic activity from which (part of) the noise is likely created. The memory characterization of the noise gives additional means to distinguish the natural sources of noise that is polluted by the anthropogenic sources in the recordings. Carniel et al., 2008b, also suggests that the memory can possible be affected by regional tectonic events, though there were few observed examples within the study period.
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