Abstract:In this paper, we select the focal mechanism solution data of 36 shallow-focus earthquakes that satisfies M≥7.0 from January 1, 1976 to December 24, 2016 on the south America plateau, drawing from the global CMT catalog. We use Coulomb3.3 to calculate the static coulomb stress changes in the subsequent earthquake fault surface, and discuss whether there is a stress-triggered effect from previous earthquakes to subsequent earthquakes. The results show that, as the trigger threshold is 0.1 bar, 11 earthquakes are triggered by the previous earthquakes; the triggered earthquakes are 31.4 % of the total; there are 7 suppressed earthquakes and 17 uncertain earthquakes; 22 of the earthquakes have a positive static coulomb failure stress change, which accounts for 62.9% overall. Based on the research results above, we draw the conclusion that there have been some stress triggering effects between the south America plateau strong earthquakes since 1976.
YANG Jian,SHENG Shuzhong,WAN Yongge et al. Study on Stress Triggering of Strong Shallow-Focus Earthquakes in South America Since 1976[J]. jgg, 2018, 38(6): 634-638.