Geological hazard zonation and land use planning assessment in the South Eastern Marlborough Sounds, New Zealand

The Marlborough Sounds, located at the top of the South Island, New Zealand (Figure 1.), is well known for its scenic beauty. However, the areas is less well known for the high degree of weathering and instability associated with the steep slopes. There is a high demand for land in the south eastern Marlborough Sounds due to urban expansion from Picton and Waikawa. Increasingly, the land being selected for house sites is on steeper and potentially more unstable land.

Quaternary climactic influences saw the beginning of the deep weathering profile typical of the Marlborough Sounds today. Periglacial and interglacial periods assisted in the preferential weathering of shear zones and the development of significant amounts of regolith and colluvial material overlying the schistose and greywacke bedrock.