A dynamic landscape
When James Cook first arrived in New Zealand, in 1769, the ship’s naturalist, Joseph Banks, described the country as ‘in general mountainous, especially inland, where probably runs a chain of very high hills’. 1 It would fall to future explorers and surveyors to map the country’s interior, but it was already clear that New Zealand, with its high mountains and fast-flowing rivers, was very different to England, which had rolling hills and sluggish rivers. What made New Zealand’s landscape so dynamic?
At the time of Cook’s visit, most Europeans believed in the biblical creation story, which said that God had made the world in seven days (estimated to be 4004 BC), and that catastrophic events like the Great Flood shaped the land.
Māori had their own traditions. After the legendary hero Māui fished up the North Island with his magic hook, the landscape was formed by fire-brandishing tohunga and powerful ancestors. Lakes were hollowed out with digging sticks, and volcanoes showed where fires were lit. Waka (canoes), the ancestors who sailed in them, and the cargo they carried became manifest as the mountains, hills and rocks.
Uniformitarianism: ongoing processes
Scientists who studied the landscape had other explanations. By the mid- to late 19th century, the study of how landforms were created (later called geomorphology) was dominated by the theory of uniformitarianism. This suggested that landscapes were formed by continuous or ‘uniform’ natural processes. The present was the key to the past, and the earth’s shaping forces were still active. For example, erosion by rain, rivers and the sea shaped the land’s surface, and earthquakes and volcanoes caused uplift.
The first European geologists to systematically describe New Zealand’s landforms were Ferdinand Hochstetter and Julius Haast. In late 1858 and during 1859 Hochstetter and Haast travelled to Auckland, Waikato, the central North Island and Nelson. Haast later surveyed west Nelson and Canterbury. Hochstetter wrote widely about New Zealand over the next decade, in German and English, and incorporated many of Haast’s ideas about the South Island. Hochstetter’s influential book New Zealand: its physical geography, geology and natural history (1867) was the first to use uniformitarianism to interpret the New Zealand landscape.
Hochstetter was very perceptive. For example, he suggested that the lake basins of the ‘volcanic Taupo Zone’ formed in depressions (calderas) created after major volcanic eruptions. He also recognised Lake Taupō as a major source of the pumice found throughout the North Island.