How complex is the 2016 Mw 7.8 Kaikoura earthquake, South Island, New Zealand?

Publication Type:

Journal Article

Source:

Science Bulletin, Volume 62, p.309-311 (2017)

URL:

http://hdl.handle.net/10220/42290

Abstract:

<p><span>A powerful earthquake of moment magnitude (M</span><span>w</span><span>) 7.8 occurred in the Kaikoura region, South Island, New Zealand, at 00:02:56</span><span>&nbsp;</span><span>AM (local time), 14 November 2016. According to the Institute of Geological and Nuclear Sciences (GNS) in New Zealand, the earthquake epicenter was at 42.69</span><span>&nbsp;</span><span>°S, 173.02</span><span>&nbsp;</span><span>°E, about 90</span><span>&nbsp;</span><span>km northeast of Christchurch, the 3rd largest city in New Zealand (</span><a name="bf0005" href="http://www.sciencedirect.com/science/article/pii/S2095927317300518#f0005" class="workspace-trigger">Fig.&nbsp;1</a><span>a). GNS reported a focal depth of 15</span><span>&nbsp;</span><span>km. The main shock of the Kaikoura earthquake sequence lasted about 2</span><span>&nbsp;</span><span>min with the most severe shaking occurring about 50</span><span>&nbsp;</span><span>s after the hypocenter origin time. Four large aftershocks of M</span><span>w</span><span>&nbsp;6.0–6.5 (</span><a name="bf0005" href="http://www.sciencedirect.com/science/article/pii/S2095927317300518#f0005" class="workspace-trigger">Fig.&nbsp;1</a><span>b) occurred within 13</span><span>&nbsp;</span><span>h of the main shock according to the United States Geological Survey (USGS). The total number of aftershocks exceeded 2000 by 17 November 2016. The rupture exceeded 150</span><span>&nbsp;</span><span>km (</span><a name="bf0005" href="http://www.sciencedirect.com/science/article/pii/S2095927317300518#f0005" class="workspace-trigger">Fig.&nbsp;1</a><span>a, b), from south of the eastern Hope fault, northeastward, to Cape Campbell, including ∼34</span><span>&nbsp;</span><span>km of offshore rupture along the northeast-trending Needles fault (Ref.&nbsp;</span><em>NIWA</em><span>,&nbsp;</span><a href="http://niwa.co.nz/news/scientists-detect-huge-fault-rupture-offshore-fro... target="_blank">http://niwa.co.nz/news/scientists-detect-huge-fault-rupture-offshore-fro...).</span></p>