Where are the main fault lines in New Zealand?

The main fault lines in New Zealand can be grouped into two major systems:

1. The Alpine Fault: The Alpine Fault runs about 450 miles (720 kilometers) along the South Island of New Zealand. It is the boundary between the Pacific and Australian plates. The displacement on this fault is horizontal and can reach several meters per year. The fault is responsible for uplifting of the Southern Alps and many of the major earthquakes in New Zealand's history.

2. The Hikurangi Subduction Zone: The Hikurangi Subduction zone runs about 620 miles (1000 kilometers) along the east coast of the North Island of New Zealand. This fault line marks the boundary between the Pacific Plate, which is subducting beneath the Australian Plate. It forms a subduction zone and is characterized by reverse faults. The Hikurangi Subduction Zone poses a substantial seismic and tsunami risk to the North Island.

In addition to these two major systems, there are also several other fault lines in New Zealand, including the Marlborough Fault System in the South Island and the Wellington Fault in the North Island.