Most ancient rocks
This map focuses on the top of the South Island, and shows some of Aotearoa’s oldest and youngest rocks.
The Tasman region’s hills and mountains contain the country’s oldest geological features. Between Takaka and Karamea lie ancient blocks of crooked mountains and valleys. These rocks formed during the Cambrian period, when life was restricted to the seas.
The youngest rocks are typically those found in coastal river valleys and floodplains. The Wairau and Awatere valleys are the most recently formed parts of Marlborough. Rivers have transported gravels down from the mountains and created substantial coastal floodplains. Along with a favourable climate, well-draining soils are the basis of the region’s extensive vineyards.
How to read
The palest tones represent the youngest landscapes. The darker the colour, the older the bedrock.