Phreatomagmatic eruptions are defined as juvenile forming eruptions as a result of interaction between water and magma. They are different from magmatic and phreatic eruptions. The products of phreatomagmatic eruptions contain juvenile clasts, unlike phreatic eruptions, and are the result of interaction between magma and water, unlike magmatic eruptions. It is very common for a large explosive eruption to have magmatic and phreatomagmatic components.

Phreatomagmatic eruptions are defined as juvenile forming eruptions as a result of interaction between water and magma. They are different from magmatic and phreatic eruptions. The products of phreatomagmatic eruptions contain juvenile clasts, unlike phreatic eruptions, and are the result of interaction between magma and water, unlike magmatic eruptions. It is very common for a large explosive eruption to have magmatic and phreatomagmatic components.