Spatial Temporal Condition of Recent Seismicity In The Northern Part of Sumatra

Abstract

The condition of stress and recent seismicity in the seismic-prone area can be statistically analyzed with the Gutenberg-Richter relation. We apply this relation to the hypocenter distribution for the period 1970-2020 with M ≥ 4 and depth ≤ 200 km  in the northern part of Sumatra. Spatially, The results obtained, a-values and b-values, figure a lateral heterogeneity and stress accumulation with dense structures at the interface zone in the subduction system and the northern segmentation of the Seulimeum fault. In time, both zones illustrate a slow time-to-failure cycle and seismic gap with high stress accumulation in the specific clusters with high seismic parameter values. The results of the spatial temporal analysis illustrate that each major earthquake event is usually preceded by a low statistical parameter value.