Mt Tarawera erupted in the early morning of 10 June 1886. By 8.00pm that night Sir James Hector, Director of the New Zealand Geological Survey and the Colonial Museum (Te Papa’s predecessor), was on the Government steamer Hinemoa headed north to investigate. His mission was to determine the extent to which the ‘volcanic line’ was erupting.
Hector’s first stop was White Island, where he found no volcanic activity. From there he travelled to Tauranga and then south to Ohinemutu (Rotorua) by horse. Assistant geologist James Park journeyed with him, and in Tauranga Hector commissioned photographer Charles Spencer to record what they were witnessing. The party visited Lake Rotomahana on June 14 and 15, and took in the Taupo, Tongariro, and Ruapehu volcanoes after that. After returning to Wellington by steamer from Napier, Hector submitted his report – the eruption was confined to Tarawera and it was over.
The Tarawera eruption was the ultimate sound and light show. An explosive and spectacular event, it happened at night and the ‘explosions’ could be heard as far north as the Bay of Islands and as far south as Christchurch. This meant that most of the population of New Zealand heard it!
The expansive eruption commenced at 1.30am at Wahanga (northern dome of Tarawera), then moved southwards to Ruawahia (middle dome and the highest peak), Tarawera (southern dome), Lake Rotomahana, and Waimangu.
This eruption was remarkable because it was short-lived, lasting only until 6.00am, and involved explosive fire fountaining of basalt (dark volcanic rock) lava, phreatic (caused by the heating and expansion of underground water) explosions, pyroclastic (containing hot ash, lava fragments, and gases) flows, and lahars (flows of volcanic debris) along a 19 kilometre-long fissure.