 Cerro Azul is responsible for several of South America 's largest recorded eruptions , in 1846 and 1932 . In 1846 , an effusive eruption formed the vent at the site of present @-@ day Quizapu crater on the northern flank of Cerro Azul and sent lava flowing down the sides of the volcano , creating a lava field 8 – 9 square kilometres ( 3 – 3 @.@ 5 square miles ) in area . Phreatic and Strombolian volcanism between 1907 and 1932 excavated this crater . In 1932 , one of the largest explosive eruptions of the 20th century occurred at Quizapu Crater and sent 9 @.@ 5 cubic kilometres ( 2 @.@ 3 cu mi ) of ash into the atmosphere . The volcano 's most recent eruption was in 1967 . 
