2016 Ecuador earthquake

==Geology==
Ecuador lies above the [[destructive boundary|destructive plate boundary]] where the [[Nazca Plate]] is [[Subduction|subducting]] beneath the [[South American Plate]]. The convergence rate between the plates in Ecuador is {{convert|61|mm|in|abbr=on}} per year. The depth, location and [[focal mechanism]] of the earthquake are all consistent with rupture along the plate interface in the form of a [[megathrust earthquake]]. [[1906 Ecuador–Colombia earthquake|A major earthquake in 1906]] ruptured the plate interface for at least 400&nbsp;km immediately northeast of the 2016 event.<ref name="USGS-Muisne" />

In this particular event, the plate boundary [[earthquake rupture|ruptured]] a 80 × 60 km<sup>2</sup> area at a depth of between 15 and 44 km. The rupture failed to propagate towards the trench; ceasing about 60 km away. A maximum slip of 2.5 meters was estimated, while the average slip across the rupture was 0.7 meters.<ref name="Heidarzadeh">{{cite journal |author1=Mohammad Heidarzadeh |author2=Satoko Murotani |author3=Kenji Satake |author4=Tomohiro Takagawa |author5=Tatsuhiko Saito |title=Fault size and depth extent of the Ecuador earthquake (Mw 7.8) of 16 April 2016 from teleseismic and tsunami data |journal=Geophysical Research Letters |date=2017 |volume=44 |issue=5 |pages=2211–2219 |doi=10.1002/2017GL072545|bibcode=2017GeoRL..44.2211H |s2cid=132506664 |url=https://bura.brunel.ac.uk/handle/2438/14824 }}</ref>

The earthquake ruptured a part of the plate boundary that had previously ruptured in another [[1942 Ecuador earthquake|magnitude 7.8 quake in 1942]].<ref name="Heidarzadeh" /> The similar aftershock distribution and rupture characteristics suggest the 2016 event was a repeat of the earthquake in 1942.<ref name="Lingling" /> The 1942 earthquake marked the beginning of a supercycle of earthquakes re-rupturing the entire boundary previously broken during the large 1906 event. The last earthquake in the supercycle occurred in [[1979 Tumaco earthquake|1979]]. Another earthquake in [[1958 Ecuador–Colombia earthquake|1958]] also formed part of the supercycle.<ref name="Lingling">{{cite journal |author1=Lingling Ye |author2=Hiroo Kanamori |author3=Jean-Philippe Avouac |author4=Linyan Li |author5=Kwok Fai Cheung |author6=Thorne Lay |title=The 16 April 2016, MW 7.8 (MS 7.5) Ecuador earthquake: A quasi-repeat of the 1942 MS 7.5 earthquake and partial re-rupture of the 1906 MS 8.6 Colombia–Ecuador earthquake |journal=Earth and Planetary Science Letters |date=15 November 2016 |volume=454 |pages=248–258 |doi=10.1016/j.epsl.2016.09.006 |bibcode=2016E&PSL.454..248Y |doi-access=free }}</ref>