Chile triple junction

This triple junction is unusual in that it consists of a mid-oceanic ridge, the Chile Rise, being subducted under the South American plate at the Peru–Chile Trench.

The Antarctic plate started to subduct beneath South America 14 million years ago in the Miocene epoch forming the Chile triple junction.

At first the Antarctic plate subducted only in the southernmost tip of Patagonia, meaning that the Chile triple junction lay near the Strait of Magellan.

Several authors have suggested that subduction erosion or slip during earthquakes may be responsible for the uplift of the Coastal Cordillera, a trench-parallel morphostructural system in north Chile.

The O'Higgins seamount group, surrounded by a topographic swell, acts as a barrier between the north and south half of the Chile Trench.

The Chile triple junction, a geologic junction off the southern coast of Chile where the South American, Nazca and Antarctic tectonic plates meet
The Nazca plate and Antarctic plate are colliding with the South American plate at the Chile triple junction.