Acoustic Emission Monitoring of the Syracuse Athena Temple: Scale Invariance in the Timing of Ruptures

We perform a comparative statistical analysis between the acoustic-emission time series from the ancient Greek Athena temple in Syracuse and the sequence of nearby earthquakes. We find an apparent association between acoustic-emission bursts and the earthquake occurrence. The waiting-time distributions for acoustic-emission and earthquake time series are described by a unique scaling law indicating self-similarity over a wide range of magnitude scales. This evidence suggests a correlation between the aging process of the temple and the local seismic activity.

Figure 1

Accumulated number (black line), instantaneous AE rate averaged over 1 h (red line) in the temple pillar, and nearby earthquake occurrence (triangles) as functions of time.

Figure 2

Map of Sicily showing the location of the monitored site (yellow square) and epicenters (black circles) of nearby earthquakes (listed in Table ) that occurred during the monitoring period.

Figure 3

Applied load (solid line) and accumulated number of AE events (dashed line) as functions of time.

Figure 4

Rescaled waiting-time PDFs for the period preceding the peak load (a) and for the whole duration test (b), for several $V_{\mathrm{th}}$ values, equivalent to $M_{\mathrm{th}}=\log (V_{\mathrm{th}}/1\mu \mathrm{V})$. The data collapse illustrates the fulfilment of a scaling law, where the solid line is the scaling function of Eq. (5).

Figure 5

Waiting-time PDFs for five seismic magnitude thresholds $M_{\mathrm{th}}$ and four AE signal thresholds $V_{\mathrm{th}}$ (a) and their collapse onto a single curve illustrating the fulfilment of a common scaling law (b).