Relationship between Seismicity and Subduction Parameters
Speaker: Zi-Jun Lin Adviser: Jing-Yi Lin
Abstract
Based on global earthquake catalogs of worldwide subduction plate interface earthquakes were extracted for the period between 1900 and 2007. Assuming that the seismogenic zone coincides with the distribution of 5.5 ≤ M < 7 earthquakes, the subduction interface seismogenic zones were mapped for 80% of the trench systems and characterized with geometrical and mechanical parameters. Using this database, correlations were isolated between significant parameters to identify cause‐effect relationships.
The subduction velocity was the first‐order controlling parameter for variations in the physical characteristics of plate interfaces, determining both the geometry and mechanical behavior As such, the fast subduction zones and cold slabs were associated with large and steep plate interfaces, which had large seismic rates. The subduction velocity could not account for the potential earthquake magnitude diversity that was observed along the trenches.
Events with Mw ≥ 8.5 preferentially occurred in the vicinity of slab edges, where the upper plate was continental and the back‐arc strain was neutral.
Reference
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