How Lava Lakes Form — And Why They're So Rare
A lava lake sounds simple: a pool of molten rock sitting in a volcanic crater. But maintaining one is an extraordinary balancing act that almost no volcano on Earth can pull off.
You need four things simultaneously: an open vent that doesn't seal itself with solidified lava, a continuous supply of magma from a reservoir below, a convection cycle where hot magma rises and cooler material sinks back down the conduit, and a thermodynamic equilibrium between heat input from below and radiative/convective heat loss at the surface. If the magma supply stutters, the lake solidifies. If the vent widens too much, the lake drains. If the conduit clogs, it's over.
That's why temporary lava lakes form during lots of eruptions — Kilauea, Etna, and others regularly produce them — but persistent ones lasting years or decades are vanishingly rare. Of the 1,400+ potentially active volcanoes on Earth, only 8 currently maintain anything resembling a stable lava lake. And even those come and go: Ambrym's twin lakes collapsed in 2018, Kilauea's crater drained completely in 2018 and refilled in 2020, and Nyiragongo's has drained twice in the last 25 years.
By VolcanoDB Research Team. Data: USGS, Smithsonian Global Volcanism Program, individual volcano observatories.
Every Permanent Lava Lake on Earth
Here are all 8, ranked by how long they've been active. Each links to its volcano page in our database.