Halema‘uma‘u lava lake, Kīlauea summit eruption—March 22, 2021

Crustal foundering—less-dense liquid lava overriding and sinking thin surface crust—is common in the lava lake within Halema‘uma‘u, at the summit of Kīlauea. Here, large sections of the crust are foundering, resurfacing the lake. USGS photo by M. Patrick on March 22, 2021.