Galán is located in Argentina

Cerro Galán is a caldera in Catamarca Province, Argentina, considered to be the best exposed large caldera in the world. It was formed 2.2 million years ago when 1,050 km of material was erupted, producing ignimbrite deposits stretching up to 100 km away. The caldera was originally the site of a large lake, but resurgence of the eastern caldera floor has confined the salty Laguna Diamante to the caldera's western edge.

• http://en.wikipedia.org/wiki/Galán