Here's another "alien-esque" terrain map, though it could be terran too. This is my version of a deep sea smoker - a hot spot emitting sulferous energy from volcanic tunnels beneath, escaping into the atmosphere above it. You could use this as bottom of the sea, but I'd consider this an alien planet with a heavy barometric pressure surface requiring a vaccuum suit to breath. Anyway, the deep sea smoker... enjoy!

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