Lava Lakes: The Exposed Guts of Volcanoes

(via Amusing Planet) Most volcanoes have a deep inner chamber of molten rocks, but this chamber is typically capped shut by cooled, solid rock. But sometimes the magma chamber is exposed at the top of the volcano in a giant caldera of rolling, bubbling and spluttering lava. This happens when an active volcanoes continuously pushes new molten rocks up the vent forming a pool inside the caldera while solidified lava sinks back into the depth to be re-melted. Volcanologists often describe lava lake as “windows into the heart of volcanoes.”