In the third stage, Vulcanian eruptions took place at Huaynaputina and deposited another ash layer, which is thinner than that produced by the first stage eruption and appears to be partly of phreatomagmatic origin. During this stage the volcano also emitted lava bombs; the total volume of erupted tephra is about . This third stage destroyed the lava dome and formed the third vent, which then began to settle along the faults as the magma underneath the vent was exhausted. The fourth vent outside of the amphitheatre formed late during the eruption as well.