SeisComPlex
 Thodoris Aspiotis Feed


Tsallis Entropy - NoN Extensive Statistical Physics.
Complexity Theory via Seismological observations.

Compatible on Unix , Linux & Windows O.S.

q-Gaussian Processing
Matlab & Python Software

Feb. 2020

EGU2020-8190 Dynamical evolution of the seismic coda wave increments during the 2011-2012 Santorini's caldera unrest. A Non-Extensive Statistical Physics approach. by Theodoros Aspiotis et. al.

Santorini’s caldera unrest during 2011-2012 led several studies to raise the important question of whether seismicity is associated with an impending and potential volcanic eruption or it just relieves the accumulated tectonic energy. In the present work we study seismic coda waves generated by the local earthquake events prior, during and after the seismic crisis that occurred inside the caldera. Coda waves are interpreted as scattered seismic waves generated by heterogeneities within the Earth, i.e. by faults, fractures, velocity and/or density anomalies, etc. In particular, we utilize the three components of the seismograms recorded by three seismological stations on the island of Santorini and estimate the duration of the coda waves by implementing a three step procedure that includes the signal-to-noise ratio, the STA/LTA method and the short time Fourier transform. The final estimation was verified or redefined manually due to ambient seismic noise. Due to the nature and the path complexity of the coda waves and towards achieving a unified framework for the study of the immerse geo-structural seismotectonic complexity of the Santorini volcanic complex, we use Non-Extensive Statistical Physics (NESP) to study the probability distribution functions (pdfs) of the increments of seismic coda waves. NESP forms a generalization of the Boltzmann-Gibbs statistical mechanics, that has extensively been used for the analysis of semi-chaotic systems that exhibit long-range interactions, memory effects and multi-fractality. The analysis and results demonstrate that the seismic coda waves increments deviate from the Gaussian shape and their respective pdfs could adequately be described and processed by the q-Gaussian distribution. Furthermore and in order to investigate the dynamical structure of the volcanic-tectonic activity, we estimate the q- indices derived from the pdfs of the coda wave time series increments during the period 2009 - 2014 and present their variations as a function of time and as a function of the local magnitude (m L ) of the events prior, during and after the caldera unrest. Further research will use ambient seismic noise in order to verify the spatiotemporal variations of the q-indices and their correlation with the volcanic-tectonic structure of the Santorini caldera.




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National & Kapodistrian University of Athens
Seismology and Geophysics

SeisComPlex V1.0 Msc. Thesis
Supervisor: Prof. F. Vallianatos

Developer: Ted Aspiotis

Release date: February 22, 2020

Operating Systems: Windows & Linux

Contact: theodoros.aspiotis at kaust.edu.sa

tedaspiotis at geol.uoa.gr