1 Analysis of the Complexity of Seismic Data Sets: Case Study for Caucasus Teimuraz Matcharashvili 1,2 , Tamaz Chelidze 1 , Zurab Javakhishvili 2 , Natalya Zhukova 1 , Nato Jorjiashvili 2 , Ia Shengelia 2 , Ekaterine Mepharidze 1 , Aleksandre Sborshchikovi 1 1 M. NODIA INSTITUTE OF GEOPHYSICS, TBILISI, GEORGIA 2 ILIA STATE UNIVERSITY, TBILISI, GEORGIA CHAPTER OUTLINE 1.1 Introduction ..................................................................................................................................... 3 1.2 Data .................................................................................................................................................. 5 1.2.1 Waiting Times and Earthquake Interdistances ................................................................... 5 1.2.2 Ambient Seismic Noise .......................................................................................................... 6 1.3 Methods of Analysis ....................................................................................................................... 7 1.4 Results of Analysis ........................................................................................................................ 11 1.4.1 Waiting Times and Earthquake Interdistance Analysis .................................................... 11 1.4.2 Ambient Seismic Noise Data Analysis ................................................................................ 14 1.5 Conclusions .................................................................................................................................... 21 Acknowledgement ............................................................................................................................... 21 References ............................................................................................................................................. 22 1.1 Introduction Several decades ago, geophysical objects and events in Earth sciences were mainly consid- ered as either random or deterministic. Complexity analysis reveals the enormous domain of structures and processes ranging from complete randomness to behaviour that can be considered as more or less deterministic. Modern tools of data analysis help to assess the extent of complexity in natural processes (Abarbanel and Tsimring, 1993; Kantz and Schreiber, 1997; Strogatz, 2000; Sornette, 2000; Sprott, 2003; Webber and Marwan, 2015). There are many definitions of complexity. Almost all stress the following main properties of 3 Complexity of Seismic Time Series. DOI: https://doi.org/10.1016/B978-0-12-813138-1.00001-8 © 2018 Elsevier Inc. All rights reserved.