Lava delta

Aerial view of lava delta (center, left of volcanic fume) growing seaward at Kamoamoa on Kilauea Volcano, Hawai`i.

Lava entering the sea often builds a wide fan-shaped area of new land called a lava delta. Such new land is usually built on sloping layers of loose lava fragments and flows. On steep submarine slopes, these layers of debris are unstable and often lead to the sudden collapse of lava deltas into the sea.