TY - JOUR
T1 - The 16 April 2016, MW 7.8 (MS 7.5) Ecuador earthquake
T2 - A quasi-repeat of the 1942 MS 7.5 earthquake and partial re-rupture of the 1906 MS 8.6 Colombia–Ecuador earthquake
AU - Ye, Lingling
AU - Kanamori, Hiroo
AU - Avouac, Jean Philippe
AU - Li, Linyan
AU - Cheung, Kwok Fai
AU - Lay, Thorne
PY - 2016/11/15
Y1 - 2016/11/15
N2 - The 2016 Ecuador MW7.8 earthquake ruptured the subduction zone boundary between the Nazca and South American plates. Joint modeling of seismic and tsunami observations indicates an ∼120 km long rupture area beneath the coastline north of the 1998 MW7.2 rupture. The slip distribution reveals two discrete asperities near the hypocenter and around the equator. Their locations and the patchy pattern are consistent with the prior interseismic geodetic strain, which showed highly locked patches also beneath the coastline. Aftershocks cluster along two streaks, one aligned nearly parallel to the plate convergence direction up-dip of the main slip patches, and the other on a trench-perpendicular lineation south of the 1958 rupture zone. Comparisons of seismic waveforms and magnitudes show that the 2016 event and 1942 earthquakes have similar surface wave magnitude (MS7.5), overlapping rupture areas, and similar main pulses of moment rate. The same area ruptured as the southernmost portion of the larger earthquake of 1906 (MW8.6, MS8.6). The seismic behavior reflects persistent heterogeneous frictional properties of the Colombia–Ecuador megathrust.
AB - The 2016 Ecuador MW7.8 earthquake ruptured the subduction zone boundary between the Nazca and South American plates. Joint modeling of seismic and tsunami observations indicates an ∼120 km long rupture area beneath the coastline north of the 1998 MW7.2 rupture. The slip distribution reveals two discrete asperities near the hypocenter and around the equator. Their locations and the patchy pattern are consistent with the prior interseismic geodetic strain, which showed highly locked patches also beneath the coastline. Aftershocks cluster along two streaks, one aligned nearly parallel to the plate convergence direction up-dip of the main slip patches, and the other on a trench-perpendicular lineation south of the 1958 rupture zone. Comparisons of seismic waveforms and magnitudes show that the 2016 event and 1942 earthquakes have similar surface wave magnitude (MS7.5), overlapping rupture areas, and similar main pulses of moment rate. The same area ruptured as the southernmost portion of the larger earthquake of 1906 (MW8.6, MS8.6). The seismic behavior reflects persistent heterogeneous frictional properties of the Colombia–Ecuador megathrust.
KW - 2016 Ecuador earthquake
KW - Ecuador–Colombia earthquake sequence
KW - re-rupture of 1942 event
KW - source rupture model
UR - http://www.scopus.com/inward/record.url?scp=84992585821&partnerID=8YFLogxK
U2 - 10.1016/j.epsl.2016.09.006
DO - 10.1016/j.epsl.2016.09.006
M3 - Article
AN - SCOPUS:84992585821
SN - 0012-821X
VL - 454
SP - 248
EP - 258
JO - Earth and Planetary Science Letters
JF - Earth and Planetary Science Letters
ER -