QuakeCoRE Seminar: New Zealand National Seismic Hazard Model: Key Features & Analysis Tools (2023)

QuakeCoRE Seminar Series: New Zealand National Seismic Hazard Model (NSHM): Key Features and Analysis Tools - Matt Gerstenberger (2023)

Presenter: Matt Gerstenberger (GNS Science | Te Pū Ao)

This presentation was held on Friday 12 May 2023

Abstract: In this Seminar we will introduce some of the key concepts behind the NSHM including: 1) important changes when compared to past NSHMs including their implications for the hazard; and, 2) the available tools for accessing and understanding the results. One important change has been an emphasis on modelling and communicating the range of the future hazard, rather than just a single estimate. This better reflects our understanding of earthquake occurrence and means the best hazard estimate is now a distribution. Other key changes include how geological and geophysical datasets are used to constrain crustal deformation rates; how we model complex ruptures on faults; the use of a forecast period of 100 years that includes aspects of clustering and time-dependence (rather than a nominally time-independent forecast); the development of models specifically for lower seismicity regions; the development of new databases for constraining ground motion models; the use of numerous international ground motion models; and two new models ground motion models that have been developed for New Zealand. We will discuss how these changes have impacted the hazard forecasts.

The NSHM results include additional quantification of uncertainty that was not available in the past. We will discuss where this uncertainty comes from and how to understand what it means for the results. Finally we are continually developing and improving tools for accessing and analysing the results on the NSHM webpage and we will introduce how to use and understand these tools and results.

Bio: Matt Gerstenberger has been the Programe Lead for the New Zealand NSHM since 2012. His primary work has centred around the development of hazard and risk assessment models with a particular focus on understanding uncertainty and time-dependence. He has also been actively involved in many earthquake responses over the last 20 years. This includes working with GNS’ earthquake hazard and risk forecasting teams to provide forecasting data and probabilistic modelling to assist in the event response and recovery phases. He initially joined GNS Science in 1996 and received his PhD in Seismology from ETH-Zurich in 2003.

For more information on future Seminars please visit our website, here: https://bit.ly/2023QCSeminarSeries