Cerro Redondo (dome)

22°22′S 66°08′W^[1]Cerro Redondo is a lava dome complex in the northern Puna,^[1] north of Rinconada.^[2] It is situated over the Ordovician basement east of the Sierra de Rinconada. The lava domes were erupted along ring fractures on a preceding fall deposit containing blocks and breccia.^[1] Another report indicates just one isolated dacite dome.^[2] Intense hydrothermal alteration has occurred on the lavas.^[3]

The breccia and pyroclastics are 12.54±1.1 mya old, determined from fission track dating of apatite.^[2] The complex may be linked to a caldera together with the neighbouring Chinchillas and Pan de Azúcar centres. Each of them is associated with mineral deposits which were mined on Pan de Azúcar.^[1] Cerro Redondo's breccia is flanked by normal faults and one reverse fault is located within the complex.^[2]