Statistical Analysis of Earthquake Occurrences in and around the Çaldıran Fault Zone (Turkey)


Alkan H. , Öztürk S., Akkaya İ.

6th INTERNATIONAL CONFERENCE ON MATHEMATICS “An Istanbul Meeting for World Mathematicians”, İstanbul, Turkey, 21 - 24 June 2022, pp.1-8

  • Publication Type: Conference Paper / Full Text
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.1-8

Abstract

In the scope of this study, a statistical assessment of earthquake behaviors in the Çaldıran Fault Zone and its surroundings is achieved by using the seismotectonic b-value of Gutenberg-Richter relation, probability, and return periods of the earthquakes. Multiple parameters evaluation between these variables is considered for the possible future earthquake forecasting and current hazard assessment. For the analyses, a homogeneous database including 6169 earthquakes with 1.0≤Md 5.6 between July 12, 1975 and December 29, 2021 was used. Completeness magnitude is estimated as 2.6 for the study region and the b-value of magnitude-frequency distribution is calculated as 1.07±0.09. This result shows that the b-value of the study area is well represented by the Gutenberg-Richter scaling law. Regional distribution of b-value indicates that the areas having the lower b-values (<1.0) are generally observed in all parts of the study region including the Çaldıran fault consisting of Alaçayır, Hidirmenteş and Gülderen segments, Hasan Timur fault, Dorutay fault, and Saray fault zone. The probabilities earthquake occurrences with Md=6.0 in Tr = 10, 20, 50, 70 and 100 years are estimated as about 4 %, 7 %, 18 %, 23 % and 32 %, respectively. Also, the return periods of Md=5.0, 5.5, and 6.0 earthquakes are calculated as about 29, 90, and 300 years, respectively. The results of probabilities and return periods suggest that earthquake occurrences ranging from 3.0-4.5 magnitude levels are more likely than those of the other occurrences in the short term. Çaldıran Fault zone and its adjacent region are very active seismically and tectonically, and many strong/destructive earthquakes occurred in the historical and instrumental periods; the last of these major earthquakes occurred on November 24, 1976 (MS=7.3). As a remarkable fact, the results of the present study can be used as a promising guide for earthquake forecasting and further hazard potential in this part of Turkey in the intermediate and long terms.