Temporal and spatial variations of Gutenberg-Richter parameter and fractal dimension in Western Anatolia, Turkey


BAYRAK E., YILMAZ Ş. , BAYRAK Y.

JOURNAL OF ASIAN EARTH SCIENCES, vol.138, pp.1-11, 2017 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 138
  • Publication Date: 2017
  • Doi Number: 10.1016/j.jseaes.2017.01.031
  • Title of Journal : JOURNAL OF ASIAN EARTH SCIENCES
  • Page Numbers: pp.1-11

Abstract

The temporal and spatial variations of Gutenberg-Richter parameter (b-value) and fractal dimension (D-c) during the period 1900-2010 in Western Anatolia was investigated. The study area is divided into 15 different source zones based on their tectonic and seismotectonic regimes. We calculated the temporal variation of b and D-c values in each region using Zmap. The temporal variation of these parameters for the prediction of major earthquakes was calculated. The spatial distribution of these parameters is related to the stress levels of the faults. We observed that b and D-c values change before the major earthquakes in the 15 seismic regions. To evaluate the spatial distribution of b and D-c values, 0.50 degrees x 0.50 degrees grid interval were used. The b-values smaller than 0.70 are related to the Aegean Arc and Eskisehir Fault. The highest values are related to Sultandagi and Sandikli Faults. Fractal correlation dimension varies from 1.65 to 2.60, which shows that the study area has a higher D-c value. The lowest D-c values are related to the joining area between Aegean and Cyprus arcs, Burdur-Fethiye fault zone. Some have concluded that b-values drop instantly before large shocks. Others suggested that temporally stable low b value zones identify future large earthquake locations. The results reveal that large earthquakes occur when b decreases and D-c increases, suggesting that variation of b and D-c can be used as an earthquake precursor. Mapping of b and D-c values provide information about the state of stress in the region, i.e. lower b and higher D-c values associated with epicentral areas of large earthquakes. (C) 2017 Elsevier Ltd. All rights reserved.