Lava cave

A lava cave is any cave formed in volcanic rock, though in typical use it usually means caves formed by volcanic processes, which are more properly termed volcanic caves. Sea caves, and other sorts of erosional and crevice caves, may be formed in volcanic rocks, but are unrelated to volcanic processes and typically form long after the volcanic rock was emplaced.

There are many types of lava caves, with these being the most notable:

Rift cave

Inflationary cave

Lava mold cave

Open vertical volcanic conduit

Pit crater with an inner pit, an open vertical volcanic conduit

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