Colourful Crater Lakes
By Ludy Andria
Mount Kelimutu located in Flores Island is famous for its colourful crater lakes. The locals name them Tiwu Ata Mbupu (Lake of the Elderly),Tiwu Nuwa Muri Koo Fai (Lake of the Young and Maidens) and Tiwu Ata Polo (Sacred Lake). They are usually blue, green and red in colour, and vary periodically.
Why these crater lakes has different colours?
Here’s the summary of Pasternack and Varekamp (1994) geochemistry study:
- Tiwu Ata Polo (TAP) is an intermediate “acid-saline” volcanic crater lake whose frequent color changes are probably the direct result of changes in the oxidation state of the lake’s water. TAP is intermediate in volcanic activity relative to the other Keli Mutu lakes.
- Tiwu Nua Moori Koohi Fah (TiN) is a “cool acid-brine” volcanic crater lake that contains exotic sulfur compounds and probably a host of copper-rich minerals in the sediments. Of the three Keli Mutu lakes, TiN is presently experiencing the greatest fumarolic input, which may include a flux of ~85 tonnes of sulfur dioxide per day (~55MW energy output).
- Tiwu Ata Mbupu (TAM) is an “acid-sulfate” volcanic crater lake whose gaseous input is presently very small relative to those for the other Kelimutu lakes. In the 1970s it appears that TAM was much more active than it presently is.
- Comparison of the individual lakes with their respective historic chemistries demonstrates that they are all approaching chemical steady state.
- Several seepage outlets exist on and around Kelimutu. The river Watu Gana bears a strong TAP fluid signature, but other hydrothermal waters show no crater lake signature at all.
How to get there?
The nearest city is Ende. Pelita Air and Merpati fly regularly to Ende from Denpasar, Bali.