 There are about 50 volcanoes with recent activity in the Central Volcanic Zone, and additional volcanoes exist in the Northern Volcanic Zone and the Southern Volcanic Zone, two other volcanic belts north and south.The volcanic arc runs along the borders between Bolivia and Argentina with Chile, and behind the volcanic arc lies a chain of silicic volcanoes, of which Galán is a southern member.The whole region has been subject to substantial ignimbrite-forming volcanism with many eruptions producing volumes of rock larger than , although the actual vents often are only visible from space imagery.