The Influence of Spatial Variations of Gutenberg-Richter Parameter (b-value) in the Red Sea Seismicity

The Spatial variations of Gutenberg-Richter parameter b-value during the period 1990 to 2014 in The Red Sea was calculated. The study area was divided into 4 different seismic sub-regions. We calculated the spatial variation of b-value in the whole study area of the red sea and in each sub-region separately. The distribution of the b-value is related to the stress levels of the faults. We observed that b-value changes before the major earthquakes in the 4 seismic regions to evaluate the spatial distribution of seismic hazards. The b-values equals to 0.86 is relating to the region (1) that is at the northern part of the Red Sea. The two-middle regions (2) and (3) are about 1.34 and 0.98 respectively. While the Southern region (4) is approximately 0.94. Some have concluded that the b-values drop instantly before large shocks. Others suggested that temporally stable low b-value zones identify future large earthquake locations. Mapping of b-value distribution provides information about the state of stress in that region, i. e. lower b-values associated with epicentral areas of large earthquakes as in region (1) and (4). While higher b-value associated with small earthquakes as in case of region (2) and (3). Bayrak et al. (2017).