AE monitoring of the Syracuse Athena Temple: Scale invariance in the timing of ruptures

We present a comparative statistical analysis between the time series of the acoustic emission (AE) events detected from the ancient Greek Athena temple in Syracuse (Eastern Sicily, UNESCO World Heritage List since 2005), and the time series of small and intermediate earthquakes occurred in this part of Sicily during the AE monitoring period. The waiting-time distributions for both time series and different magnitude thresholds are described by a unique scaling function indicating self-similarity over a wide range of magnitude scales. The similarity between the waiting times in AEs and earthquakes suggests a correlation between the microfracturing process accompanying ageing and deterioration of the monument and the regional seismicity. Our results reveal that the structure of the Athena temple is particularly sensitive to the normal seismic activity, suggesting structural AE monitoring as a useful tool for seismic hazard assessment.