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New Zealand’s National Petrology Reference Collection at GNS Science includes samples of radioactive and asbestiform minerals and rocks. The legislative requirements for managing these potentially hazardous samples have recently changed because the Radiation Safety Act, Radiation Safety Regulations and Health and Safety at Work (Asbestos) Regulations were revised in 2016-2017. Steps have been taken at GNS Science to ensure legislative requirements are met, and procedures put in place to safely store and manage radioactive and asbestiform-bearing samples within the collection. These procedures may have application to other curated geological collections at New Zealand universities and museums involving potentially hazardous materials. [ABSTRACT FROM AUTHOR]

Paleoseismology has been making an important contribution to understanding the Alpine Fault and the hazard it poses to society. However, evidence of past earthquakes comes from a wide variety of sources and publication of the evidence has been somewhat fragmented. Here, we review physical evidence for past large to great earthquakes on the Alpine Fault to summarise current understanding, illustrate progress and highlight future directions. Paleoseismic evidence has been derived from tree disturbance, landscape features and trenches across the fault. These records have been supplemented and extended back in time with sedimentary evidence of Alpine Fault earthquakes from fault-proximal lakes and wetlands. In this review, we update radiocarbon analyses using recent calibration curves and modern Bayesian statistical methods where necessary to enable comparison between on-fault, fault-proximal and off-fault earthquake records. Over recent decades, Alpine Fault paleoseismology has progressed from playing an important role in demonstrating that large surface-rupturing earthquakes occur, to enabling estimates of earthquake recurrence behaviour, shaking intensities, rupture extents, landscape response durations and likelihood of the next earthquake. [ABSTRACT FROM AUTHOR]

Soil samples collected at 50–70 cm depth at 8 km-spaced sample sites over 40,000 km2 of southern New Zealand were analysed for their chemical composition. Nine pathfinder elements (Ag, As, Au, Bi, Mo, Sb, Sn, Te, W), which are useful in exploration for orogenic-style mineralisation, were z-score normalised using two different matrices to account for both lithology and metamorphic grade, which vary significantly across the survey area. Interrogation of interpolated plots of the normalised data, relative to known orogenic-style deposits (Au ± Sb ± W), highlights chemical associations that varied between deposit types, and between similar deposit types mineralised under varying pressure-temperature-time conditions. Active mining for orogenic-style Au along the Hyde-Macraes Shear Zone is coincident with a regionally-significant, multi-element soil anomaly (Ag, As, Au, Mo, Sn, Te, Sb, W). The chemical associations vary along strike of the mined-portion of the shear, such that the northwest has high Ag, Au, Mo, Sn, and Te relative to the southeast which has high Sb, W in soil anomalies, hinting at chemical complexity along the shear. The chemical footprint of this deposit is readily identified in the 8 km-spaced grid, considerably expanding the chemical footprint previously inferred from hard-rock studies. Historic orogenic W mines are associated with high As, Au, Bi, W in soil anomalies, and historic Sb mining with high Bi in soil anomalies. Chemical soil anomalies are likely related to the progressive metamorphic breakdown of minerals, especially rutile and pyrite. Several multi-element soil anomalies that are coincident with known orogenic mineralisation, also occur in areas that have not been mined, and explored only at a reconnaissance level. This study demonstrates the importance of normalisation of chemical data in complex geological settings and highlights the value that can be extracted beyond only plotting raw-concentration, single-element maps, and the significant opportunity in multielement studies of soil in mineral exploration for orogenic-style mineralisation. • Soil samples from 8 km-spaced sample sites over 40,000 km2 of New Zealand • Nine orogenic Au pathfinder elements standardised for lithology/metamorphic grade • The footprint of the Macraes deposit is readily identified in the 8 km-spaced grid. • Important to normalise chemical data, especially in complex geological settings • Significant value that can be extracted beyond raw-concentration, single-element maps [ABSTRACT FROM AUTHOR]