TY - JOUR
T1 - Structural Control on Megathrust Rupture and Slip Behavior
T2 - Insights From the 2016 Mw 7.8 Pedernales Ecuador Earthquake
AU - Soto-Cordero, Lillian
AU - Meltzer, Anne
AU - Bergman, Eric
AU - Hoskins, Mariah
AU - Stachnik, Joshua C.
AU - Agurto-Detzel, Hans
AU - Alvarado, Alexandra
AU - Beck, Susan
AU - Charvis, Philippe
AU - Font, Yvonne
AU - Hayes, Gavin P.
AU - Hernandez, Stephen
AU - Lynner, Colton
AU - Leon-Rios, Sergio
AU - Nocquet, Jean Mathieu
AU - Regnier, Marc
AU - Rietbrock, Andreas
AU - Rolandone, Frederique
AU - Ruiz, Mario
N1 - Publisher Copyright:
©2020. The Authors.
PY - 2020/2/1
Y1 - 2020/2/1
N2 - The heterogeneous seafloor topography of the Nazca Plate as it enters the Ecuador subduction zone provides an opportunity to document the influence of seafloor roughness on slip behavior and megathrust rupture. The 2016 Mw 7.8 Pedernales Ecuador earthquake was followed by a rich and active postseismic sequence. An internationally coordinated rapid response effort installed a temporary seismic network to densify coastal stations of the permanent Ecuadorian national seismic network. A combination of 82 onshore short and intermediate period and broadband seismic stations and six ocean bottom seismometers recorded the postseismic Pedernales sequence for over a year after the mainshock. A robust earthquake catalog combined with calibrated relocations for a subset of magnitude ≥4 earthquakes shows pronounced spatial and temporal clustering. A range of slip behavior accommodates postseismic deformation including earthquakes, slow slip events, and earthquake swarms. Models of plate coupling and the consistency of earthquake clustering and slip behavior through multiple seismic cycles reveal a segmented subduction zone primarily controlled by subducted seafloor topography, accreted terranes, and inherited structure. The 2016 Pedernales mainshock triggered moderate to strong earthquakes (5 ≤ M ≤ 7) and earthquake swarms north of the mainshock rupture close to the epicenter of the 1906 Mw 8.8 earthquake and in the segment of the subduction zone that ruptured in 1958 in a Mw 7.7 earthquake.
AB - The heterogeneous seafloor topography of the Nazca Plate as it enters the Ecuador subduction zone provides an opportunity to document the influence of seafloor roughness on slip behavior and megathrust rupture. The 2016 Mw 7.8 Pedernales Ecuador earthquake was followed by a rich and active postseismic sequence. An internationally coordinated rapid response effort installed a temporary seismic network to densify coastal stations of the permanent Ecuadorian national seismic network. A combination of 82 onshore short and intermediate period and broadband seismic stations and six ocean bottom seismometers recorded the postseismic Pedernales sequence for over a year after the mainshock. A robust earthquake catalog combined with calibrated relocations for a subset of magnitude ≥4 earthquakes shows pronounced spatial and temporal clustering. A range of slip behavior accommodates postseismic deformation including earthquakes, slow slip events, and earthquake swarms. Models of plate coupling and the consistency of earthquake clustering and slip behavior through multiple seismic cycles reveal a segmented subduction zone primarily controlled by subducted seafloor topography, accreted terranes, and inherited structure. The 2016 Pedernales mainshock triggered moderate to strong earthquakes (5 ≤ M ≤ 7) and earthquake swarms north of the mainshock rupture close to the epicenter of the 1906 Mw 8.8 earthquake and in the segment of the subduction zone that ruptured in 1958 in a Mw 7.7 earthquake.
KW - aftershock sequence
KW - megathrust rupture
KW - subduction zone earthquakes
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U2 - 10.1029/2019JB018001
DO - 10.1029/2019JB018001
M3 - Article
AN - SCOPUS:85080987086
SN - 2169-9313
VL - 125
JO - Journal of Geophysical Research: Solid Earth
JF - Journal of Geophysical Research: Solid Earth
IS - 2
M1 - e2019JB018001
ER -