Pomerape is a complex of lava domes, accompanied by lava flows which were emplaced atop of the domes. It was active about 200,000 years ago. The lava domes formed first and were later buried by the actual volcanic cone, which unlike the rhyolitic-dacitic domes is formed by hornblende andesite. The Chungará Andesites and lava dome complex of Parinacota were laid down at this time. Pomerape is associated with an adventive vent that has erupted mafic magmas. The main cone was last active 106,000 +- 7,000 years ago, the adventive vent is dated to 205,000 ± 24,000 years ago.