Tiwu Ata Mbupu (Lake of Old People) is usually blue and is the westernmost of the three lakes. The other two lakes, Tiwu Nuwa Muri Koo Fai (Lake of Young Men and Maidens) and Tiwu Ata Polo (Bewitched or Enchanted Lake) are separated by a shared crater wall and are typically green or red in colour, respectively.
The colour changes are a result of chemical reactions accredited to the minerals contained in the lake as a result subaqueous fumaroles.
Fumaroles are openings in the Earth's crust which emits steam and gases such as carbon dioxide, sulfur dioxide, hydrogen chloride, and hydrogen sulfide.
This is the only place in the world where this colour changing phenomenon occurs!
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