Two large Holocene eruptions have been identified at Melimoyu, called MEL1 and MEL2 and whose deposits are known as the La Junta and Santa Ana tephras respectively. The larger MEL1 eruption occurred between 2,790 - 2,740 years ago and produced a layered basaltic-dacitic tephra consisting of pumice with lithics and scoria inclusions. The MEL2 eruption took place about 1,680 ± 100 calibrated radiocarbon years ago and consists of pumice of andesitic composition. MEL1 deposits have thicknesses of depending on the layer at distance of the volcano, while MEL2 units rech thicknesses of at the same distance.