Chile Earthquakes Mw6.9 and Mw6.7
Posting Date: 11 March 2010
Location: Libertador O'Higgins region, central Chile
Peril: Earthquake
On Thursday, 11 March two large aftershocks of the Mw8.8 Chile earthquake have struck the Libertador O’Higgins region of central Chile. Firstly, a strong magnitude 6.9 (moment magnitude) earthquake occurred at 14:40 UTC (11:40 am local time).
The USGS have released a preliminary fixed depth estimate of 22 miles (35 km) and a preliminary epicentral location of 34.251S, 71.889W, approximately 65 miles (105 km) west of Rancagua, Chile; 80 miles (135 km) north-northwest of Talca, Chile; 85 miles (135 km) south-southwest of Valparaiso, Chile; and 90 miles (145 km) southwest of Santiago, Chile. According to the USGS Shakemap, 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. Further away from the epicentral region, according to the USGS, Santa Cruz experienced intensity VI shaking, while Rancagua and Talca may have experienced intensity V shaking. At this early stage it is not thought that Valparaiso, Vina del Mar and Santiago have experienced significant shaking from this earthquake. Initial reports are of windows rattling in the capital Santiago, but there have been no reports of damage.
15 minutes later the same region was struck by a strong magnitude 6.7 (moment magnitude) earthquake. This second earthquake occurred at 14:55 UTC (11:55 am local time) and the USGS have assigned a preliminary fixed focal depth of 22 miles (35 km) and a preliminary epicentral location of 34.263S, 71.782W, 60 miles (95 km) west of Rancagua; 80 miles (130 km) north of Talca; and 85 miles (135 km) south of Valparaiso; and 85 miles (135 km) southwest of Santiago. The location of the epicenter of the second earthquake is approximately 6 miles (10 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. Immediate damage reports are scarce; however RMS will continue to monitor the media and liaise with our Reconnaissance team in Chile and update this Cat Activity report when further information comes to light.
DISCLAIMER: Copyright 2012 Risk Management Solutions Inc. All
Rights Reserved. This information is provided "as is," without any warranties or
representations, express, implied or statutory, including without limitation, warranties
of non-infringement, merchantability or fitness for a particular purpose.