A volcanogenic lake is a lake formed as a result of volcanic activity.[1] They are generally a body of water inside an inactive
volcanic crater (
crater lakes) but can also be large volumes of molten
lava within an active volcanic crater (
lava lakes) and waterbodies constrained by lava flows,
pyroclastic flows or
lahars in valley systems.[2] The term volcanic lake is also used to describe volcanogenic lakes, although it is more commonly assigned to those inside volcanic craters.[3][4][1][2]
These are some examples of rare lava lakes where molten lava in a volcano maintains relative equilibrium, neither rising to overflowing nor sinking to drain away.