1987 Edgecumbe earthquake
|Date||Monday 2 March 1987, 1:42 pm NZDT (UTC+13)|
|Depth||8 kilometres (5 mi)|
|Areas affected||New Zealand|
|Casualties||0 dead, 35 injured|
The Edgecumbe earthquake of 1987 measured 6.3 on the Richter scale and struck the Bay of Plenty region of New Zealand on 2 March 1987 just after 1.42 pm, centred on the town of Edgecumbe. The earthquake was very shallow, being centred approximately 8 km from the Earth's surface. The earthquake was one of the most damaging New Zealand's North Island has experienced in recent decades, with approximately 50% of the houses in Edgecumbe being damaged by the quake. There was extensive damage to a local milk factory, with large storage tanks toppled. Kawerau was another nearby town that suffered damage and Whakatane was also badly shaken. An 80-tonne New Zealand Railways DC class locomotive was thrown onto its side.
The earthquake caused no fatalities; one person died at the time as a result of a heart attack, possibly due to the quake. A foreshock just minutes before had cut the power supply and many people had moved away from heavy machinery and out of their houses. The largest aftershock was measured at 5.2 and struck at 1.52 pm.
A crack 7 kilometres (4.3 mi) long opened in the Rangitaiki Plains near Edgecumbe as a result of the earthquake. It is now known as the 'Edgecumbe Fault'. At one point, the land close to the fault dropped 2 metres (6.6 ft).
The epicentre of the quake was approximately 2.24 kilometres (1.39 mi) south-south-east of the town of Matata, or 15 kilometres (9.3 mi) north-north-west of Edgecumbe. The intense ground shaking caused by the earthquake led to a large number of ground surface failures, including sand boils, ridge-top shatters and debris avalanches on steeper slopes.
- McSaveney, Eileen (1 December 2010). "Historic earthquakes - The 1987 Edgecumbe earthquake". Te Ara - the Encyclopedia of New Zealand. Archived from the original on 7 January 2011. Retrieved 13 February 2011.
- "1987 Edgecumbe earthquake". Rumblings Issue 19. Earthquake Commission. July 2009. Archived from the original on 2 January 2011. Retrieved 13 February 2011.
- "M 6.5, Edgecumbe, March 2 1987". GeoNet. Retrieved 13 February 2011.
- "Earthquake: Edgecumbe". Christchurch City Libraries. Retrieved 13 February 2011.
- New Zealand Department of Scientific and Industrial Research Staff (1987). "The March 2, 1987, Earthquake Near Edgecumbe, North Island, New Zealand". Eos 68: 1162–1171.
- Franks, C.A.M. (1988). "Engineering geological aspects of the Edgecumbe, New Zealand earthquake of 2 March 1987". Quarterly Journal of Engineering Geology 21 (4): 337–345. doi:10.1144/GSL.QJEG.1988.021.04.06.