Earthquake in Peru

And it’s a big one – magnitude 8.0 according to the USGS. The preliminary moment tensor solution indicates a shallowly dipping thrust fault, with a rupture depth of 33 km.

So this looks like a subduction thrust earthquake (the convergent plate boundary between the Nazca and South American plates is the purple line in the image above), but it was deep enough that the rupture did not propogate all the way to the surface and generate a tsunami. Unfortunately, because it was deeper along the subduction thrust, the epicentre was actually beneath the Chilean coast itself, meaning that the towns and villages there have got a severe shaking. Such a powerful quake, in a country which lacks rigourously applied building codes, has caused the expected havoc.