Talk provided by Dr. Chris Rollins from GNS Science on November 14, 2024 as part of the SZ4D International Webinar Series. March 27 marked 60 years since the great 1964 M=9.2 Alaska subduction earthquake, the second largest ever recorded. The 1964 earthquake was hugely important for many reasons, including as a live illustration of the developing idea of plate tectonics and of all the cascading hazards that can arise from subduction earthquakes. For Aotearoa New Zealand – whose capital Wellington sits on a crossover between subduction and strike-slip tectonics – the 1964 earthquake also illustrated what might be a worst-case scenario: a subduction zone and several overriding upper-plate faults rupturing together in a single massive earthquake.