1942 Ecuador earthquake

A subduction zone exists off the coast of Ecuador and Colombia due to oblique convergence between the continental South American plate, and oceanic Nazca plate. The rate of convergence between these plates is estimated at per year. The Carnegie Ridge is a submarine feature which extends from the Galápagos Islands to some point east of the trench. Its collision and subduction introduces asperities and other characteristics that would not be present without. Its buoyancy, for example, may help to lock the plate interface in that area. Modelling of interplate deformation along the coast shows higher amounts of deformation – which is directly related to the locking – in Ecuador compared with Colombia. The buoyancy and locking of the plate interface appears to change both the dynamics of seismicity and the tsunamigenic potential of the subduction zone in the sense that the ridge can act as a barrier to fault ruptures. ==Earthquake==

The earthquake struck near the coast of Ecuador on 13 May at 21:13 ECT. It measured 7.8–7.9 on the moment magnitude scale, had a hypocentral depth of , and an epicenter about west of Pedernales. The 1942 earthquake was the first in a sequence of shocks that would re-rupture the Ecuador–Colombia subduction zone since 1906; subsequent events would occur in 1958 and 1979. In 2016, a 7.8 earthquake ruptured the portion of the subduction zone that was involved in the 1942 event, north of a 1998 rupture. The 2016 event caused of slip, which is indicative of the accumulated strain while it was locked. The earthquakes of 1942 and 2016 (with epicenters just apart) are part of a cycle with an average recurrence interval of 74 years, indicating the next event may occur around 2090. ==Impact==

The earthquake caused more than 300 deaths across Ecuador and million in damage. Despite being about from the epicenter, the city of Guayaquil experienced the heaviest damage. More than 100 people died there, and numerous high-rise buildings collapsed. Most of Guayaquil sustained moderate damage evaluated on the Mercalli intensity as VI–VII (Strong–Very strong). Several reinforced concrete buildings the downtown area were heavily damaged and corresponded with IX (Violent). In the central, southern, and western parts of the city, situated on loose soil, the damage was evaluated at VIII (Severe), while areas on harder bedrock experienced VI (Strong) intensity. Forty people were killed by collapsed buildings; the greatest loss of life occurred at the corner of Pichincha and Colón streets when a five-storey clinic collapsed. In the same area, electricity and tram services were disrupted. Three buildings with four or five floors collapsed while others with three floors or more were heavily damaged. The greatest degree of damage occurred on the first floor of these buildings. Fractured columns and walls, toppled facades, and tilting occurred in other buildings. Three buildings had beams on their first floor so badly damaged that supports had to be installed immediately before they could be repaired or demolished. Additionally, two strong aftershocks rocked the coast of Ecuador, causing more panic. During the night, many residents of Guayaquil slept in public parks or in their vehicles. The earthquake also caused disruption and damage to water infrastructure such as leaks at various places, forcing services to be limited to a few hours at certain times of the day. However, within a week, most pipelines were repaired. Electrical and telephone services were also affected, plunging the city into darkness, and in other instances, these service were intentionally cut to prevent short circuits and fires. ==See also==