High resolution environmental and volcanic histories recorded in Auckland maar crater lakes, Northern New Zealand.


Paul Augustinus

Faculty of Science

Project code: SCI010

Laminated lake sediment sequences that span the last 250 ka infill deep volcanic lakes in the Auckland Volcanic Field (AVF), in northern New Zealand. On-going studies into the volcanic ash-based eruption histories of the AVF and Taupo Volcanic Zone volcanic centres focus on the Auckland maar crater records and they can be easily fingerprinted with respect to their source eruptions. These ash layers are essential for development of core chronologies, correlation between cores, as well as volcanic hazard assessment. Here we propose a refinement of the history of eruptions to have impacted on the Auckland region using a novel combination of micro-XRF core scanning and more traditional sedimentological, mineralogical and geochemical approaches. In particular, micro-XRF core scanning is capable of enabling rapid identification of microscopic tephra that until recently have not been considered in Auckland region volcanic hazard assessments.