Seddon Earthquakes of 2013
Marlborough is no stranger to earthquakes, sitting as it does on its own fault system, lying at the boundary of the Alpine Fault and the Kermadec Trench.
However, the swarm of quakes that struck in the winter of 2013 proved both shocking and destructive for residents – particularly those of the small Seddon community.
The first major quake struck on 21 July, about 20km east of Seddon, at a depth of 17kms and measuring 6.5 on the moment magnitude scale. It caused minor damage in the region, with more significant impact in Wellington, but was followed by a series of aftershocks.
The most damaging quake was yet to come. On 16 August a second quake hit. This is now known as the Lake Grassmere Earthquake, and measured 6.6, with an epicentre only 10km south east of Seddon, 8km in depth. The earthquake caused significant land damage in the local area, with landslips blocking roads, including the main highway between Blenheim and Christchurch. Most of the buildings in Seddon were damaged in some way, with many declared uninhabitable. The quake was felt strongly in Blenheim and a number of businesses closed as damage was assessed. The quake swarm continued over several weeks, unnerving residents.
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The most immediate danger for Seddon was the Halden Dam, lying in the headwaters above Seddon and close to the quake’s epicentre. The dam suffered severe cracking, and houses downstream were evacuated, while the dam was drained over several days.
The community gathered around to support the residents of Seddon as people came to terms with the impact of the quakes. Affected businesses, amongst them many wineries and the Grassmere saltworks, soon reopened with minimal long term effects, however in the aftermath one third of the houses in the vicinity of Seddon were left empty, with eight uninhabitable and eleven restricted. As in Christchurch, the restoration of buildings was inevitably slow, particularly as the threat of earthquakes continued. Many families have left the area, possibly never to return.
Listen to Radio New Zealand's Insight, broadcast 1 December 2013: Recovery from the Seddon Shakes. Alison Hossain returns to Seddon to find out how the area is recovering in the run up to Christmas.
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Further sources - Seddon Earthquakes of 2013
- Hicks, G. & Campbell, H. (2012) Awesome Forces: the natural hazards that threaten New Zealand. Wellington, N.Z. : Te Papa Press
- Rogers, A. (2013) The shaky isles : New Zealand earthquakes. Wellington, New Zealand : Grantham House
- Fear and triumph (2013, August 21) Marlborough Express.
- Grapes. R. (2000) The Seddon earthquake [of 1966]. In Marlborough; just over 150 years of earthquakes. Nelson Historical Society Journal, 6(3)
- Severe earthquake near Seddon (2013, August 16). Marborough Express
- Wardle P. (2013, August 21) Work intensifies to avoid dam breach. Marlborough Express
- Wineries in clean up mode with damage to tanks and walkways (2013, August 19) Marlborough Express.
- Animation 48 hours of earthquakes in Seddon
- Fenaughty, Kevin (17 August 2013). "Damaging quake hits the north-east of the South Island". Geonet. GNS Science. Retrieved 17 August 2013
- King. K. Historic house ruined by Seddon quake (2013, August 17). Retrieved from 3News:
- Large earthquakes strike Seddon, felt around New Zealand. Retrieved from Newstalk ZB, August 16, 2013.
- New Zealand Earthquake Report -- Magnitude 6.6, Friday, August 16 2013 at 2:31:05 pm (NZST)". GNS Science. Retrieved 17 August 2013
- Quake pushes Blenheim to the east (2013, 24 July) GNS Science:
- Yesterday's Seddon magnitude 6.5 Earthquake (2013, 22 July) Retrieved from Te Ara