Evolution of b-values before large earthquakes of mb ≥6.0 in Andaman region

Authors

  • SHWETA PRASAD Dept. Geology and Geophysics, IIT Kharagpur, India.
  • C. SINGH Dept. Geology and Geophysics, IIT Kharagpur, India.

DOI:

https://doi.org/10.1344/GeologicaActa2015.13.3.3

Keywords:

Gutenberg–Richter relation, b-value, Resolution, Andaman earthquake

Abstract

We have considered six earthquakes of mb ≥6.0, with focal depths within 45 km, in Andaman region during 2000 to 2012 to examine the spatial variations of b-value at epicentre within a one-year period prior to the occurrence of the earthquakes. We have found a correlation between the low b for the one year time interval and the occurrence of large events. The epicentral b-values of six earthquakes are lower than 1.0 and five out of six earthquakes show very low b-value at the epicentre. Our study may indicate that b-value can be employed as a possible precursor for the forecasting of a major earthquake.

 

Author Biographies

SHWETA PRASAD, Dept. Geology and Geophysics, IIT Kharagpur, India.

MSc. Integrated Student, Exploration geophysics, Geology and Geophysics, IIT Kharagpur, India

C. SINGH, Dept. Geology and Geophysics, IIT Kharagpur, India.

Assistant Professor, Geology and Geophysics, IIT Kharagpur, India

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2015-07-08

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