CT scanning reveals downward tephra injectites

This week we analysed the internal structure of the sediment cores we collected at Rotoroa, Rotokaeo, and Waiwhakareke using a medical CT scanner at Hamilton Radiology. This method provides a first estimation about whether or not seismites (tephras deformed by earthquake activity) are present in the sedimentary record. Next week we plan to cut the cores lengthwise for detailed sediment description and sampling.

Sediment cores were scanned using a new medical CT scanner at Hamilton Radiology. From left to right: Dr Vicki Moon, Dr Max Kluger, Jordanka Chaneva, and Nic Ross
X-ray image of a sediment core, which shows downward injection structures from (tentatively) Rotorua tephra layer into underlying organic-rich host sediments
CT image of sediment core. Upper left: Downward injection structures from (tentatively) Tuhua and Mamaku tephras

UoW team presents research at Waikato Regional Hazards Forum

Members of the Tephra Seismites group and colleagues from UoW Earth Sciences attended the annual Waikato Regional Natural Hazards Forum at Hauraki District Council, Paeroa, on Friday 20 November. They joined colleagues from district and regional councils, Civil Defence and Emergency Management, and other research institutes to hear about and discuss aspects of natural hazard management and mitigation, with a focus on community engagement.

The Waikato team, including four (post)graduate students, gave a series of short ‘lightning talks’ on current research about newly-discovered faults in Hamilton and the liquefaction potential of lacustrine ash layers.

Jordanka Chaneva, PhD student with the Tephra Seismites group, gives an overview of plans to analyse tephra (ash) layers in lake sediments using geotechnical methods, to understand how they deform during earthquakes
Some of the University of Waikato attendees (From top left: George McQuillan, Dr Vicki Moon, Dr Max Kluger, Dr Adrian Pittari, Dr Willem de Lange, Prof David Lowe, Tori Gibbons, Dr Tehnuka Ilanko, and Jordanka Chaneva)