Background-Plus on Chile's Latest Earthquakes

A few weeks ago, as I sat at my desk outside the central Chilean city of Talca, a low rumble passed through the ground – in area that suffered dramatic damage in the monumental earthquake of 2010. It was brief and, as a resident of Northern California, this tremor didn’t especially disturb me. Over the next couple weeks, though, I read about frequent seismic activity in northernmost Chile, in and around the port city of Iquique (pictured below) and, last Tuesday, a big one struck.

According to the US Geological Survey, the April 1 event measured 8.2 on the Richter scale, with its epicenter 59 km northwest of Iquique. This would put it almost directly opposite the semi-ghost town of Pisagua (pictured below), an erstwhile nitrate port that also, infamously, served as a de facto prison camp in the early days of the Pinochet dictatorship. Both Pisagua and Iquique occupy wave-cut terraces that are vulnerable to seismic seawaves, and reports say that a two-meter tsunami hit Iquique’s harbor, destroying numerous small fishing boats.

There are also cracked pavement on local streets and landslides in desert canyons that have blocked roads, but only a handful of deaths – the Atacama desert, unlike the Chilean heartland south of Santiago, is thinly populated and the quality of construction is relatively high. There are few adobe buildings in Iquique, as much of its historic downtown (pictured below) consists of wooden structures built of Douglas fir imported from the United States in the 19th century. Those structures are often more flexible than adobes, though they’re more vulnerable to fires.

I haven’t visited the area for almost two years but, given my long experience there, I expect the recovery to be much quicker than that of the 2010 event. Aftershocks continue, including a powerful 7.6 on Tuesday that was closer to Iquique.  Still, as the photograph below of the 1868 tsunami that struck the more northerly city of Arica shows, it could have been a lot worse.