Māori woman beside the Waikite Geyser
at Whakarewarewa, taken about 1910
( Courtesy The Encyclopedia of New Zealand)
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Waikite was once the "crown jewel" of geysers at Whakarewarewa geothermal area, but it has not produced a significant steam eruption and has not had shallow acidic fluids since 1969.
GNS Science geothermal scientist Ed Mroczek said geothermal features were naturally variable, and could be dormant for some years.
"This makes it difficult to distinguish what is part of a natural cycle and what is disruption caused by human activity," Dr Mroczek said. "Our monitoring has shown that not all geysers and springs have returned to their former state, but it is really encouraging to see signs of activity at Waikite."
Dr Mroczek said elevated levels of chloride in the hot water at Whakarewarewa indicated that pressure had increased and water from deeper in the earth was being pushed towards the surface.