Science of Tsunami Hazards (Aug 2023)
TSUNAMIS, SEISMIC SEICHES, AND UNDETERMINED WAVES ON NEW ZEALAND LAKES, 1846–2022: A NEW DATABASE, AND OVERVIEW.
Abstract
A new database of tsunamis, seismic seiches and undetermined waves (collectively called lake waves) that occurred on New Zealand lakes between1846-2022 has been compiled and summarized. Based on an extensive literature review, photographic and field evidence, the investigation is the first to collate such information on a national scale. It increases the knowledge of a poorly understood natural hazard that has occurred throughout the country and provides a basis for further research. Seventy-four lake waves were recorded, implying a much higher occurrence frequency than previously considered. Apart from meteorite impact, lake waves have been generated by all known mechanisms, from local to global scale. Eleven tsunamigenic categories were identified. Most (n = 48; 65%) have been associated with seismic shaking, either directly, or with co seismic processes. Lake waves have been recorded in all types o f l a k e s , r a n g i n g from the country’s largest to some of the smallest; some of the deepest to shallowest, and from the highest-altitude lake to those around sea level. The greatest wave height (c. 10 m), and run-up elevation (c. 20 m above the lake surface), was associated with the May 1992 Maud Lake tsunami. To date, lake waves have caused minimal property damage or personal injury, although the hazard and risk they present is predicted to increase, in association with intensifying lakeside developments and, possibly, with climate-change effects.
