Quantifying the Aftershock Sequences of Two Chilean Megathrust Earthquakes: The 2014 Iquique and the 2015 Illapel Events
Session: Subduction Processes Along Latin America Subduction Zones [Poster]
Type: Poster
Date: 4/19/2021
Presentation Time: 11:30 AM Pacific
Description:
To obtain a better understanding of the characteristics of aftershocks following megathrust earthquakes, we analyze aftershocks of the 2014 Mw 8.1 Iquique earthquake in Northern Chile from a dense and precisely relocated earthquake catalog built by Sippl et al., 2018. We first expand the aftershock catalog from 2014 to 2016 with a continuous matched-filter search using ~ 4000 template events with local magnitudes between 3.0 and 4.0. We demonstrate that aftershocks expand logarithmically with time, consistent with aftershock activity controlled by afterslip, and measure the apparent aftershock migration speeds. We further examine the relationship between aftershock density and coseismic stress drop for a range of coseismic slip models. We will then extend this framework to systematically analyze the postseismic phases of other major megathrust earthquakes, starting with the 2015 Mw 8.3 Illapel earthquake in Central Chile.
Presenting Author: Yichen Geng
Student Presenter: Yes
Authors
Yichen Geng Presenting Author Corresponding Author yichen_geng@g.harvard.edu Harvard University |
William Frank wfrank@mit.edu Massachusetts Institute of Technology |
Florent Aden-Antoniow faden@mit.edu Massachusetts Institute of Technology |
|
|
|
|
|
|
Quantifying the Aftershock Sequences of Two Chilean Megathrust Earthquakes: The 2014 Iquique and the 2015 Illapel Events
Category
Subduction Processes Along Latin America Subduction Zones