Powerful earthquake aftershocks reach 7.2 magnitude

Two large aftershocks struck Chile on Thursday 11th March 11, however immediate damage reports are scarce.

Catastrophe modelling company RMS reports that at 11:40 am local time (14:40 Greenwich Mean Time) a powerful 7.2 magnitude earthquake struck the Libertador O’Higgins region of central Chile.

The US Geological Survey (USGS) has released a preliminary fixed depth estimate of 22 miles (35 km), approximately 90 miles (150 km) southwest of Santiago and 88 miles (140 km) south-southwest of Valparaiso.

The epicentres of the two earthquakes were approximately 4.5 miles apart.

According to the USGS, the region closest to the epicenter experienced intensity VII (very strong) shaking on the Modified Mercalli Intensity (MMI) scale. Towns that may have been affected by this level of shaking include La Estrella, Litueche, Navidad, Marchihue, Reten Llico, Rapel, Poblacion and Pichilemu. Initial reports are of windows rattling in Santiago, but there have been no reports of damage in the capital city.

Fifteen minutes later the same region was struck by a strong magnitude 6.9 (moment magnitude) earthquake. This second earthquake occurred at 14:55 UTC (11:55 am local time) and the USGS have assigned a preliminary focal depth of 27.6 miles (44.4 km), around 80 miles (130 km) southwest of Santiago; and 85 miles (140 km) south of Valparaiso.

The location of the epicenter of the second earthquake is approximately 4.5 miles (7.2 km) from the first. According to the USGS ShakeMap, a similar pattern of shaking intensity occurred as in the first earthquake, with the towns of La Estrella, Litueche, Marchihue and Poblacion experiencing up to intensity VI shaking.

Both earthquakes are aftershocks of the February 27 8.8Mw earthquake in Chile. Immediate damage reports are scarce. RMS said it will continue to monitor the situation and update accordingly.