# The faults under the plains: mapped traces near Christchurch

The Greendale fault appeared on no hazard map before it ruptured on 4 September 2010. The drawn record holds 1,832 trace lines across 3 faults, about 91.3 km of mapped rupture and deformation.

## Greendale Fault (mapped 2011)
The surface rupture of the 4 September 2010 M7.2 — the fault that appeared on no hazard map until it opened.
- 1,762 trace lines · 68.6 km drawn
- Survey labels: fault ×1290, fault scarp ×330, suspected fault ×123, broad scarp ×11, broad fold ×8
## Ashley Fault Zone (mapped 2014)
The mapped zone under the northern plains, between the city and Rangiora — the active fault Christchurch knew about.
- 44 trace lines · 17.8 km drawn
## Hanmer Fault (mapped 2004)
The trace through the Hanmer basin, North Canterbury.
- 26 trace lines · 4.9 km drawn
## Also in the earthquakes

- [The sequence](https://www.chch.live/sequence), every shake since 2010, counted
- [Earthquakes, live](https://www.chch.live/quakes), the ones that just landed
- [Liquefaction](https://www.chch.live/liquefaction), the ground that moved
- [The land grades](https://www.chch.live/technical-categories), TC1, TC2, TC3
- [The red zone](https://www.chch.live/redzone), the land the Crown wrote off
- [The rebuild’s receipts](https://www.chch.live/rebuild), SCIRT’s photograph archive
- [The earthquakes, explained](https://www.chch.live/how-nz-works/canterbury-earthquakes), what happened and why
- [Liquefaction, explained](https://www.chch.live/how-nz-works/liquefaction), why the east failed
- [The rebuild, explained](https://www.chch.live/how-nz-works/rebuild), the machinery that put it back

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Environment Canterbury open data: GNS/council active-fault mapping (Public/EarthquakeFaults). A line is where the survey drew the trace or deformation, not a claim about any one address. The shakes are counted at https://www.chch.live/sequence; the story at https://www.chch.live/how-nz-works/canterbury-earthquakes. The file: https://www.chch.live/faults.json