Seismological and engineering aspects of the recent 14 November 2016 Mw7.8 Kaikoura, New Zealand earthquake
Brendon A. Bradley, University of Canterbury
Tuesday, May 30, 2017 at 1:00 PM
- Building 3, Rambo Auditorium
On 14 November 2016 at 12:02 AM local time, the magnitude Mw7.8 Kaikoura earthquake occurred along the east coast of the upper South Island, NZ. It was the largest recorded earthquake in NZ since the 1855 Mw8.2-8.3 Wairarapa earthquake. This presentation will address scientific and engineering aspects of the earthquake that have been canvased to date, as well as emerging issues that continue to surface related to the natural/built environment and societal implications.
The earthquake initiated in the Waiau Plains in North Canterbury, and involved multiple fault segments (at least 10) as the rupture generally propagated northward over 150km to Cape Campbell in Marlborough. Given the geographical proximity of the earthquake in a largely rural region of NZ, the impacts in the near-source region were largely geological and geotechnical in nature, namely surface rupture, landslides, and localized ground failure, resulting in damage to coastal transportation infrastructure and the formation of landslide dams.
Significant damage occurred to State Highway 1 (SH1) both North and South of Kaikoura and the inland Kaikoura road (SH70) from landslides and slope instability – the northern SH1 section affected is estimated to be closed for one year, leading to substantial disruption to commercial and public transportation along the island’s main highway. Relatively significant damage also occurred to numerous structures in the capital city of Wellington (located approximately 60km to the North of the causative faults) - one structure had a partial collapse of precast floor units and is the subject of an on-going government enquiry, while another three structures are undergoing rapid demolition.
As of mid-December 2016, 11% of Wellington office space was closed due to damage.