Chile Forum

Strange, I'm watching the USGS feed and there are no aftershocks. Is this a foreshock to a bigger one in the coming days?

housemate just got home, she was in a old church at a funeral mid prayer when the earthquake struck... interesting place to be!

Why am I so slow to figure out a quake is happening? o_O

Moment magnitude: 7.1 Depth: 34.8 kilometers
Time: Sunday, March 25, 2012 at 7:37:06 PM (local time)
Region: Maule, Chile
Distance to nearest population center(s): 27 km NNW of Talca, Chile; 219 km SSW of Santiago, Chile
Building code enforcement: Chile boasts a strict building code (most recently updated in 1996) that shares many traits with regulations in the U.S. The code is widely enforced for modern buildings. However, older adobe structures that do not adhere to code are still widespread in this region of Chile.
Reported damage: Minor nonstructural damage to ceilings and roofs; widespread power outages and communications disruptions.

Yesterday evening, a M7.1 earthquake struck central Chile approximately 27 kilometers north-northwest of the city of Talca (approximate population of 200,000). According to the United States Geological Survey (USGS), the earthquake occurred at 7:37 PM local time (22:37:06 UTC) and struck at a depth of 34.8 kilometers.

As a precaution, officials ordered approximately 25,000 coastal residents to evacuate in the Bio Bio and Maule regions, as original estimates placed the epicenter offshore in the Pacific Ocean. This same region was affected by the devastating M8.8 Maule quake in 2010, which generated a massive tsunami that wiped out parts of the coast. Later analysis placed yesterday’s quake onshore, which prompted Chile’s emergency officials to cancel the tsunami warning. The earthquake occurred on the subduction zone that was partially ruptured by the 2010 earthquake; it can therefore be considered another aftershock of the 2010 earthquake. It is located in the epicentral area of the 1928 M7.5 earthquake.

The USGS estimates that more than 800,000 people experienced strong shaking (Modified Mercalli Index of VI) and 9,000 people experienced very strong shaking (MMI of VII) in the Maule region. Moderate shaking was felt in Chile’s capital of Santiago (more than 200 kilometers north of the epicenter), where buildings swayed from side to side for some 20 seconds. No major damage has been reported in the affected area, including near the epicenter. Falling debris has caused a few minor injuries and there are reports of traffic accidents and landslides. The quake caused massive power outages and disruptions to mobile communications.

Reported building damage has typically been nonstructural in nature, mostly to roofs and ceilings. Chile's long history of damaging earthquakes has resulted in a strict building code, which is generally well enforced in cities. However, many buildings in rural locations and historic town centers are older structures constructed of adobe. These are widespread in the epicentral region and typically do not adhere to the country’s building code; they are characterized by poorer seismic performance than modern buildings. However, because of earthquake awareness, these adobe structures were typically built with very thick walls embedded with wood rods and straw and generally show more seismic resistance than similar construction in other regions of the world. In 2010, the Maule earthquake off Chile’s coast caused significant damage to thousands of older adobe structures. Damage to adobe structures was not reported yesterday, however, in part due to the weaker magnitude of yesterday’s quake.

AIR does not expect significant insured losses from this event.