21°53′02″S 67°54′18″W / 21.88389°S 67.90500°W[1] Cerro Chascon-Runtu Jarita is a complex of lava domes located inside, but probably unrelated to, the Pastos Grandes caldera. It is part of the more recent phase of activity of the Altiplano-Puna volcanic complex.
Accompanied with little explosive activity on the main dome Cerro Chascon, it contains ten lava domes arranged in a chain. Located in the floor of the Pastos Grandes caldera, these domes were erupted after injection of mafic magmas in the deep less than 100,000 years ago. The largest dome has a volume of 5 cubic kilometres (1.2 cu mi).