Sara Sara was active in the form of the lower Barroso and Lampa Volcanics. A first stage built up the paleo-Sara Sara edifice in the form of columnar jointed lava flows; a date obtained on this stage is 1.62 million years ago. The Lampa Volcanics were erupted by lateral vents northeast of the volcano and later buried by its eruption products and exposed by the Huanca Huanca river. During the Quaternary, explosive eruptions in a lava dome complex formed a pyroclastic fan which was later in part buried by lava flows. Fresh lava and pyroclastic flows imply recent activity, with two pyroclastic flows dated to 44,500 and 49,200 years before present.