New Zealand’s 180-million-year-old forest in Curio Bay was once part of the ancient supercontinent of Gondwana. The petrified remnants of that forest is one of the few accessible petrified forests on the planet.
During the Jurassic Period, the Curio Bay area was part of the eastern margin of the supercontinent Gondwana, which was connected to Australia and Antarctica. Most of future New Zealand lay beneath the waves at that point in history. The region was a broad, forested, coastal floodplain flanked by active volcanoes that continually destroyed the forests with massive sheets of volcanic debris. Covered with silt and mud, starved of oxygen and impregnated with silica from volcanic ash-filled floodwaters, the felled tree trunks eventually solidified and turned to rock through the process of petrification.
Over the past 10,000 years, the sea has become an archaeologist, scraping away the layers of clay and sandstone to expose this buried forest. What makes Curio Bay unique is the forest’s horizontal position due to its felling by volcanic ash-filled floodwaters. Other petrified forests, such as Arizona’s Petrified Forest and Svalbard’s Tropical Fossil Forest, are vertical. In addition, while most petrified forests are far removed from the modern forests, Curio Bay’s Petrified Forest still has its descendants in the present-day forests found closeby. About 80% of New Zealand’s trees, ferns and flowering plants are native, having evolved in isolation for millions of years. As well as native beech forests, there are forests of unique Southern Hemisphere conifers, called podocarps, whose species include rimu, totara, matai, kahikatea and miro, whose lineage stretch back to Gondwana.
When New Zealand was connected to the Antarctic margin of Gondwana, the forest grew at approximately 75-78°S latitude, well within the polar circle. The result was that ancestors of the present-day kauri and rimu trees grew in an environment that quickly changed with the seasons between long, pitch-black winters and perpetually sunny summers of continuous light. No other trees survive that are known to do this, which adds to the scientific importance of the Curio Bay site.
The recent confirmation of the mostly-underwater southern continent, which scientists have long postulated should exist, and of which New Zealand and the Lord Howe Islands are the only visible parts today, has added to the uniqueness of this area of the world. (See my previous blog on this “new” continent called “Zealandia, the Eight Continent”.)
Waves shoot up and fan out over the edge of the rock platform in Curio Bay, and the stumps of the petrified trees pop up like miniature volcanoes. Within their mini craters, there is a distinct change in colour. Unlike the grey sandstone of the rock platform, these craters are mud-orange, with circles etched in the stone. These are Jurassic tree rings.
The recently-opened information centre, called the Tumu Toka Curioscape, contains exhibits that give perspective and context to the formation of Curio Bay through interactive touch screens, wall-sized dioramas. Also included is a film that reimagines the separation of Gondwana into separate continents and the evolution of the Jurassic era that was to follow. Images of early sea life that were forerunners to today’s whales and dolphins swim across one of the screens, while on another, the giant, flightless and now extinct bird, the moa, and the tuatara flit through the forest of Curio Bay as the volcanic eruptions begin. There are tactile displays of fossilised wood, some polished so you could see the tree rings, as well as fossilised silver ferns and petrified tree roots ploughed up by local farmers.
Curio Bay’s Petrified Forest was first protected in 1928, and, in the early 1980s, the area was declared a Scientific Reserve, protecting it for further research purposes.
Well worth more study by any of my readers, and myself, and a definite bucket-list place to visit.