colourful silica terrace formed by hot water algae growing in the geothermal area of orakei korako the hidden valley, northern

alga algae area biotope called colourful deposition forest format formed geology geothermal growing hidden hot island korako landscape lime limestone new northern oceania orakei pacific polynesia rainbow river sailer sceneries seaweed sight silica sinter stone terrace valley waikato water woods yellow zealand zealandian