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Researchers from New Zealand have engaged in developing and testing earthquake forecasting models for many decades. The existing earthquake forecasting models can be classified into three categories, (1) short-term or aftershock models that describe the decay of the earthquake occurrence rate following a large event, (2) medium-term models that are variations of the Every Earthquake a Precursor According to Scale (EEPAS) model, which is based on the observation that the size and frequency of earthquake occurrence tends to increase in the vicinity of an upcoming large earthquake and aims to forecast upcoming large events in the coming months to decades, and (3) long-term models.In 2010, following the M7.1 Darfield earthquake that initiated the Canterbury earthquake sequence, GNS Science began to provide earthquake forecasts to the public. There were several further earthquake responses over the years, the largest being the 2011 M6.2 Christchurch earthquake and the 2016 M7.8 Kaikoura earthquake.A new automated seismic processing software, introduced in 2012, caused inconsistencies in the earthquake catalogue, especially with magnitudes. It has been a slow process to resolve these issues. In the meantime, we have been limited to forecast earthquakes of magnitude 5 and larger.In the future, we envisage to have an automated system provide regular earthquake forecasts to the public, and to engage more with users to provide the information that they need for decision-making in a seismic crisis and for planning for earthquake resilience., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

This report documents the acquisition and archiving of a major controlled source and passive seismic imaging project, the Seismogenesis Hikurangi Integrated Research Experiment (SHIRE). The SHIRE project aims to identify and quantify factors controlling the long-term evolution of the Hikurangi margin and the mode of slip along the subduction megathrust. The components of the data volume were acquired in two phases; between October 2017 – April 2018 (SHIRE I) and February–March 2019 (SHIRE II). The project was conducted by GNS Science; the University of Southern California, USA; the University of Texas Institute for Geophysics, USA; Victoria University of Wellington; and the Earthquake Research Institute, University of Tokyo, Japan. During SHIRE I, 5489 km of 2D seismic reflection data was collected offshore Bay of Plenty and East Coast by the R/V Marcus G. Langseth, and wide-angle refraction and reflection data were recorded onshore by 89 short-period seismograph sites along a transect from the Bay of Plenty to Gisborne and distributed array throughout the Tairāwhiti / Raukumara Peninsula. In addition, 25 short-period seismometers were located along the Bay of Plenty coast between October–December 2017. The SHIRE I land instruments also recorded signals from the 15 x 60 km volume of 3D seismic reflection data that was collected offshore Gisborne by the R/V Marcus G. Langseth during January 2018, plus four months of local and teleseismic earthquakes. SHIRE II aimed to directly image the crust beneath the Tairāwhiti / Raukumara Peninsula. Five borehole explosive sources were distributed along the central transect. The energy was recorded on 583 temporary seismograph stations comprising 304 vertical component and 269 three-component seismometers. The explosions were detonated during 26–28 February 2019. In addition, 19 SHIRE I 2D array sites were reoccupied for 20 days. The quality of the data recorded was excellent for all the explosion sources. (auth)