The 1982 El Salvador earthquake occurred southeast of San Salvador on 19 June at 00:21 local time (06:21 UTC). This undersea earthquake struck offshore in the Pacific Ocean and had a surface wave magnitude of 7.3 and a maximum Mercalli intensity of VII (Very strong). Occurring adjacent to a subduction zone at the Middle America Trench, this normal-slip shock left at least 16 and as many as 43 people dead, and many injured, and also inflicted $5 million in damage.
Near the Salvadorian coast, the Cocos Plate is subducting beneath the Caribbean Plate at the Middle America Trench. This earthquake was an intra-slab, normal-slip subduction earthquake in the subducting plate. The subduction zone and a local system of faults along the volcanic chain are two major sources of the earthquakes in El Salvador.[6]
^White, R. A.; Ligorría, J. P.; Cifuentes, I. L. (2004), "Seismic history of the Middle America subduction zone along el Salvador, Guatemala, and Chiapas, Mexico: 1526–2000", Special Paper 375: Natural Hazards in el Salvador, vol. 375, pp. 379–396, doi:10.1130/0-8137-2375-2.379, ISBN978-0-8137-2375-4