Deep sea vents are not dependant on the photosyntheic carbon cycle. https://en.wikipedia.org/wiki/Hydrothermal_vent#The_Deep_Hot_Biosphere https://en.wikipedia

Deep sea vents are not dependant on the photosyntheic carbon cycle. https://en.wikipedia.org/wiki/Hydrothermal_vent#The_Deep_Hot_Biosphere https://en.wikipedia.org/wiki/Hydrothermal_vent#The_Deep_Hot... Other extremophiles and archea exist and have been observed in deep caves and rocks. Life really does find a way!