Geologic and geomorphic impacts of the 2010-2012 Canterbury Earthquake Sequence and local evidence for large prehistoric earthquakes

Dr Mark Quigley, University of Canterbury

2013 Hochstetter Lecture and the RSNZ MB July meeting – a joint meeting with the Geoscience Society of New Zealand

7.30 pm Tuesday, 23 July, Te Manawa – Art Gallery, 326 Main Street, Palmerston North

The Canterbury earthquake sequence (CES) started with the 2010 moment magnitude (Mw) 7.1 Darfield earthquake and includes thousands of Mw ≥ 3 aftershocks, most notably the fatal 22 Feb 2011 Mw 6.2 Christchurch earthquake. The largest CES earthquakes caused geologic and geomorphic processes that changed the Canterbury landscape. Some of these changes lasted only hours and others will persist in the geologic record for 103 to 106 yrs or longer. Careful documentation of the geomorphic and geologic effects of the Canterbury earthquake sequence and comparing these with instrumental seismic data is important because it helps to define the seismic thresholds for generating these phenomena and it enables paleoseismologists to better interpret these features when they are observed in the geologic record. This talk will summarize the impacts of the CES and show new evidence for the timing, extent, and conditions of prehistoric earthquakes in this region, including penultimate rupture on the Greendale Fault, prehistoric liquefaction in eastern Christchurch, and prehistoric rockfall in the Port Hills south of Christchurch. Better attention to the geologic record will help us to avoid further land planning mistakes and increase societal and financial resilience to future earthquakes both in Christchurch and elsewhere in New Zealand.

Mark Quigley is a Senior Lecturer in Active Tectonics and Geomorphology at the University of Canterbury. Mark has active research projects in New Zealand, Australia, Tibet, Iran, Mexico, Timor Leste, and Antarctica, related to earthquakes and active tectonics, climate change and landscape processes. Due to the 2010-2012 Canterbury earthquake sequence, most of Mark’s present research is focused in Christchurch and the surrounding area of the eastern-central South Island of New Zealand. Mark has appeared in the media several hundreds of times over the last few years, participating in numerous television programmes and documentaries, and writing articles for the press, science blogs, and popular science magazines. In 2011 Mark was awarded the New Zealand Prime Minister’s Prize for Science Communication and the New Zealand Association of Scientists Science Communication Award for his work in communicating earthquake science to the public in the aftermath of the Darfield and Christchurch earthquakes. In 2012 Mark founded the SAVVY program for science communication in New Zealand in collaboration with the New Zealand Science Media Centre.

All warmly welcome