#
Natural Time Analysis: Results Related to Two Earthquakes in Greece during 2019^{ †}

^{1}

^{2}

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. Results

## 3. Discussion

## 4. Materials and Methods

#### 4.1. Natural Time Analysis (NTA)

_{− }. Again, it has been experimentally observed [4,49] that for SES activities: S

_{− }$\stackrel{<}{\phantom{\rule{0.0pt}{0ex}}\sim}$ Su.

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Abbreviations

ATH | Athens |

EQ | Earthquake |

ML(ATH) | Local EQ magnitude reported by the Institute of Geodynamics of the National Observatory of Athens |

Mw | Moment magnitude |

NTA | Natural time analysis |

PAT | Patras SES measuring station |

PIR | Pirgos SES measuring station |

SES | Seismic Electric Signals |

VAN | Varotsos Alexopoulos Nomikos |

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**Figure 1.**Map of the area ${N}_{34}^{42}{E}_{19}^{28}$ in which the locations of the SES measuring stations of the VAN telemetric network [3] operating in Greece are shown by the blue circles. The blue square corresponds to the central station operating at Glyfada, Athens (ATH), where the data are collected. The thick black line depicts the Hellenic arc [17] while the gray shaded area and the black rectangle the selectivity map of Pirgos (PIR) measuring station (see Figure 1 in [2]) and Patras (PAT) measuring station (see the rectangle with solid lines in Figure 8 in [18]), respectively. After the recording of the SES activities on 3 January 2019 at PAT and on 9 January 2019 at PIR, the areas corresponding to the selectivity maps of these two measuring stations have been reported in [14] as probable to suffer a strong EQ. The red stars correspond to the epicenters of the M${}_{w}$6.8 EQ on 25 October 2018, the Mw = 5.4 EQ on 5 February 2019, and the Mw = 5.3 EQ on 30 March 2019.

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**MDPI and ACS Style**

Sarlis, N.V.; Skordas, E.S.; Varotsos, P.A.
Natural Time Analysis: Results Related to Two Earthquakes in Greece during 2019. *Proceedings* **2019**, *24*, 20.
https://doi.org/10.3390/IECG2019-06194

**AMA Style**

Sarlis NV, Skordas ES, Varotsos PA.
Natural Time Analysis: Results Related to Two Earthquakes in Greece during 2019. *Proceedings*. 2019; 24(1):20.
https://doi.org/10.3390/IECG2019-06194

**Chicago/Turabian Style**

Sarlis, Nicholas V., Efthimios S. Skordas, and Panayiotis A. Varotsos.
2019. "Natural Time Analysis: Results Related to Two Earthquakes in Greece during 2019" *Proceedings* 24, no. 1: 20.
https://doi.org/10.3390/IECG2019-06194