TEPHRA SEISMITES

Evaluating earthquake hazards using liquefied volcanic-ash layers in lakes

Lake Ngaroto (photo by F van Schie)

Latest Updates

Tehnuka invited as ECR plenary speaker at IAVCEI 2023 volcanology conference in Rotorua

We are glad to announce that Tehnuka, who is a postdoc in our Tephra-Seismites group, will give an Early-Career Researcher Plenary talk at the volcanology conference of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) 30 Jan-3 Feb 2023. Although she is currently working with tephras, Tehnuka’s main research area until…

Liquefaction structures in Lake Rotoroa (Hamilton Lake)

M.Sc. student Richard Melchert has worked for the Tephra-Seismites group since mid 2021 and assisted with lake coring, sediment description, and other laboratory work. In his recently submitted dissertation entitled “Sedimentology and characterisation of soft-sediment deformation structures within lacustrine successions in 20,400-year-old Lake Rotoroa, Hamilton, New Zealand”, he studied liquefaction structures in Lake Rotoroa, which…

Field and lab update

The Tephra Seismites have had a particularly busy couple of months. Our coring fieldwork was completed in September, with cores collected from six further lakes. We have since completed X-ray Computer Tomography (CT) scans of all these new cores. Over the past few weeks, we cut, opened, and described all remaining cores from both of…

Project Summary

Liquefied volcanic-ash layers (‘tephra seismites’) preserved in lake sediments have never been reported. In northern New Zealand we have identified at least four such seismites in tephra-bearing lakes aged ~20,000 years in the Hamilton Basin. Our aim is to use this unique opportunity to develop a novel methodology to evaluate the frequency, possible magnitude, and likely locations of major earthquakes for the past 20,000 years in the basin. Click here to continue