Variation in b-value and Fractal Dimension of Earthquake data

Abstract

The b-value, given by Gutenberg-Richter (1954) is studied extensively by many researchers as a possible precursor of an earthquake. In this thesis, three different approaches are done to compute the b-value to observe that if b-value can be used as a precursor of earthquake. For time-based and event-based b-value observation earthquakes of magnitude grater then 2.5 (M>2.5) is taken but for spatial variation of b-value M>=1 is taken for more accurate study in smaller area. Seismicity exhibits fractal properties with respect to time, location and magnitude. In this thesis we have discussed about spatial variation of fractal dimension for all earthquakes having M>=1. We have also discussed the relation between fractal dimension and b-value prior to a large magnitude earthquake. There is a negative correlation between b-value and fractal dimension which is also collaborated by paper presented by Henderson (1999). The whole study is done in California region, near San-Andreas Fault and the data is from 2000 to 2016, taken from USGS.