Pink and White Terraces

Blomfield: The White Terraces (1884)

The Pink Terrace, or Te Otukapuarangi ("The fountain of the clouded sky") in Māori, and the White Terrace, also known as Te Tarata ("the tattooed rock"), were natural wonders of New Zealand.^[1] They were reportedly the largest silica sinter deposits on earth.^[2] Until recently, they were lost and thought destroyed in the 1886 eruption of Mount Tarawera, while new hydrothermal attractions formed to the south-west i.e. Waimangu Volcanic Rift Valley.

The Pink and White Terraces were formed by upwelling geothermal springs containing a cocktail of silica-saturated, near-neutral pH chloride water.^[3] These two world-famous springs were part of a group of hot springs and geysers, chiefly along an easterly ridge this year named Pinnacle Ridge (or the Steaming Ranges by Mundy).^[4] The main tourist attractions included Ngahapu, Ruakiwi, Te Tekapo, Waikanapanapa, Whatapoho, Ngawana, Koingo and Whakaehu.

The Pink and the White Terrace springs were ~1200 meters apart.^[5] The White Terrace was at the north-east end of Lake Rotomahana and faced west to north west at the entrance to the Kaiwaka Channel. Te Tarata descended to the lake edge ~25 metres below.^[2] The Pink Terrace lay four fifths of the way down the lake on the western shore, facing east to south-east. The pink appearance over the mid and upper basins (near the colour of a rainbow trout) was due to antimony and arsenic sulfides, although the Pink Terrace also contained gold in ore-grade concentrations.^[6]

Formation

Until recently, the Pink and White Terraces were thought to be about 1,000 years old. In 2016, Prof. Ron Keam stated the hydrothermal system which powered them may be up to 7,000 years old.^[7] The silica precipitation formed many pools and steps over time. Precipitation occurred by two methods. The ascending foundation over time formed a lip which would trap the descending flow and become level again. This process formed attractive swimming places, both for the shape and for the warm water. When the thermal layers sloped in the other direction away from the geyser, then silica steps formed on the surface. Both types of formation grew as silica-laden water cascaded over them, and the water also enhanced the spectacle. Geologist Ferdinand von Hochstetter wrote after his visit in 1859 that "doubtless thousands of years were required" for their formation.^[8]

The White Terrace was the larger formation, covering ~8 hectares and descending over ~50 layers with a drop in elevation of ~25 metres, and over a distance of ~240 metres. The Pink Terrace descended ~22 metres over a distance of ~100 meters. The Pink Terrace started at the top with a width of 75–100 meters and the bottom layers were ~27 meters wide. Tourists preferred to bathe in the upper Pink Terrace pools due to the temperature, water quality and flexibility of the pool walls.^[9]

History

Blomfield: The Pink Terraces (1884)

One of the first Europeans to visit Rotomahana was Ernst Dieffenbach. He briefly visited Rotomahana and the terraces while on a survey for the New Zealand Company^[10] in early June 1841. The description of his visit in his book "Travels in New Zealand" ^[11] inspired an interest in the Pink and White Terraces by the outside world.

The terraces were New Zealand's most famous tourist attraction, sometimes referred to as the Eighth Wonder of the World. New Zealand was still relatively inaccessible and passage took several months by ship. The journey from Auckland was typically by steamer to Tauranga, the bridle track to Ohinemutu on Lake Rotorua, by coach to Te Wairoa (the home of the missionary the Reverend Seymour Mills Spencer),^[12] by canoe across Lake Tarawera, and then on foot or by canoe up and/or down the Kaiwaka Channel; over the hill to the swampy shores of Lake Rotomahana and the terraces.^[1]

Those that made the journey to the terraces were most frequently well-to-do, young male overseas tourists or officers from the British forces in New Zealand.^[13] The list of notable tourists included Sir George Grey in 1849, Alfred Duke of Edinburgh in 1869, and Victorian novelist Anthony Trollope in 1874.^[14]

The appearance of the terraces was fortunately recorded for posterity by a number of photographers but as it was before colour photography was invented their images lack the enticing colour the formations were known for. Several artists drew and painted the terraces before their loss in 1886, most notably Charles Blomfield who visited on more than one occasion. Their atmospheric views are the main record of the Eighth Wonder of the World. The colour chemistry of the Pink terrace can be seen today at Waiotapu, where the spectacular Champagne Pool is lined with these same colloidal sulfides.^[15]

Sophia Hinerangi, sometimes known as Te Paea took over as principal guide from the older Kate Middlemass in the early 1880s, she became recognised as the principal tourist guide of the Pink and White Terraces. Sophia observed the disturbances to Lake Tarawera water levels in the days preceding the eruption.^[16] In 1885 Alfred Warbrick began guiding, though he was not from Te Tuhourangi.^[17]

Lead up to loss

A number of people mapped and commented on the region before the loss of the terraces. Dr Ferdinand von Hochstetter carried out a topographic and geological survey of the Lake Rotomahana area in 1859, producing his Geographic and Geological survey. This gave enough data to form the first map of the area and to suggest how the terraces had been formed.^[9]

In 1873 Percy Smith climbed Mt. Tarawera and gave the impression that the mountain top was rough but showed no sign of volcanic vents. In March 1881 Dr. G. Seelhorst climbed Wahanga dome and the northern end of Ruawahia dome in search of a presumed "falling star" following reports of glowing and smoke from an area behind Wahanga. In 1884 a surveyor named Charles Clayton while surveying described the top of Wahanga dome as volcanic with several depressions, one being approximately 200 feet deep.

Loss

On 10 June 1886, Mount Tarawera erupted. The eruption spread from west of Wahanga dome, 5 kilometres to the north, down to Lake Rotomahana.^[18] The volcano belched out hot mud, red hot boulders, and immense clouds of black ash from a 17-kilometre rift that crossed the mountain, passed through the lake, and extended beyond into the Waimangu valley.

After the eruption, a crater over 100 metres deep encompassed the former site of the terraces.^[18] After some years this filled with water to form a new Lake Rotomahana, 30–40 meters higher, ten times larger and deeper than the old lake.^[19][20]

Alfred Patchet Warbrick, a boat builder at Te Wairoa, witnessed the eruption of Mount Tarawera from Maunga Makatiti to the north of Lake Tarawera. Warbrick soon had whale boats on Lake Tarawera investigating the new landscape; he in time became the Chief Guide to the post-eruption attractions. Warbrick never accepted the Pink and White Terraces had been destroyed.^[21]

Rediscovery

The terraces were long thought to have been destroyed in the 1886 eruption. However, in February 2011, a team including researchers from GNS Science, Woods Hole Oceanographic Institution, Lamont-Doherty Earth Observatory, and Waikato University were mapping the lake floor when they discovered part of the Pink Terraces. The lowest two tiers of the terraces were found at 60 metres (200 ft) deep.^[22][23] A part of the White Terraces was rediscovered in June 2011.^[24] The announcement of the rediscovery of the White Terraces coincided with the 125th anniversary of the eruption of Mt. Tarawera in 1886.

The team went back in 2012 and again in February 2014 to photograph the remains, and were published in the Journal of Volcanology and Geothermal Research.^[25]

The claims of rediscovery have been challenged by skeptic Bill Keir, who calculated the 'rediscovered' structures are not where the terraces were before the eruption. Specifically, the recently discovered structures are 50–60 metres under the lake surface, but the historic terraces are expected to be as little as 10 metres under, and "could not be more than 40 metres below the surface". Keir speculates the structures discovered by the GNS team are prehistoric terraces, never before seen by humans; or perhaps step-shaped objects created by the eruption.^[26]

In 2010 Dr Sascha Nolden discovered Dr Hochstetter's archive in Basel, Switzerland and is progressively cataloging and publishing it.^[27] The archive includes Dr Hochstetter's field diaries which contain the raw data from his compass survey of Lake Rotomahana and the Pink and White Terraces. These diaries include bearings which when reverse-engineered, deliver GPS coordinates of the Pink and White Terrace locations.^[28]

Similar places

• Badab-e Surt in Iran
• Hierve el Agua in Mexico
• Mammoth Hot Springs at Yellowstone National Park in the United States
• Pamukkale in Turkey
• Terme di Saturnia in Italy

See also

• Waimangu Volcanic Rift Valley

References

External links

• Images and Paintings of the Pink and White Terraces in the collection of the Museum of New Zealand Te Papa Tongarewa
• Photos of the Pink & White Terraces
• Map of the Terraces on Te Ara

Coordinates: 38°15′38″S 176°25′50″E / 38.26056°S 176.43056°E / -38.26056; 176.43056