For students who are enrolled at a NZ or Australian University and have completed at least three years of undergraduate study. The Summer Research Scholarship provides students with opportunities to experience the challenges and rewards of research. The scholarship will have a value of $5,000.
Supervisors: David Lowe & James Beattie
Project Title: Documenting historical earthquakes and geothermal activity in the central Waikato region to help understand paleoseismicity associated with hidden faults within and near Hamilton
Hamilton’s citizens were delivered a bombshell on 1 May, 2015, when a newly-identified geological fault in the city made front-page news. At that time, little was known about it other than it may have moved in the last ~200,000 years’. Since then, dramatic discoveries have revealed a much greater potential threat: at least four hidden faults have now been identified from various lines of evidence, including offsets in exposures, LIDAR topography, geothermal and oil/gas wells, geophysical data, seismic-reflection data, river-based multibeam- echosounder and side-scan data, and paleo-liquefaction structures. Three of the faults occur in Hamilton City, one extending southward being marked by a line of geothermal springs near Temple View. All four intersect with important linear infrastructure including the Waikato Expressway, the main trunk railway, electricity, gas, and communication transmission corridors, and flood defences. Most recently, analyses of 84 cores extracted in the 1980s from 12 shallow lakes formed ~20,000 years ago in the Hamilton Basin have revealed that three volcanic ash (tephra) layers preserved in organic-bearing lake sediment have been liquefied in some (but not all) lakes by pre-historic seismic events (earthquakes), forming what we term ’tephra seismites’. Ages on these tephra seismites indicate that liquefaction-inducing shaking occurred soon after 15,500 years ago, 14,000 years ago, and 8,000 years ago. Thus there is now strong evidence that one or more of the hidden faults in the Hamilton area may have moved three times within the past 20,000 years. Reaction to the news last year resulted in a newspaper correspondent claiming (erroneously) that Hamilton is outside the active zone of shallow and deep earthquakes’ and hence there is little to worry about. The new faults and likely recent activity demonstrably show that this view is no longer tenable. Helpfully, the correspondent reported that the Waikato region has experienced several damaging earthquakes in historical times. Consequently, to provide background to the evolving geoscience-based research being undertaken on the new faults, liquefaction, and tephra seismites, we plan to undertake a summer project that aims to compile and document all recorded historical earthquake and geothermal activity in the Waikato region with a focus on the Hamilton Basin area, and to then write a refereed paper on the findings. Some reports on earthquakes and geothermal springs are available but these and other articles are of limited scope and disparate and hence we plan two objectives to meet the aim: (1) to review and evaluate documents including newspapers and published articles from scientific and historical literature dating from the 19th century through to the present on earthquakes and hot-springs; (2) to write an article about the historical earthquake and geothermal activity for a suitable refereed journal (e.g. Journal of the Royal Society of NZ). This article could include an attempt to place the historical data in the context of the new Hamilton faults and also that of the Kerepehi Fault, which occupies the adjacent Hauraki-Matamata lowlands.
Further information and applications
Feature image: University of Waikato. New Zealand Tertiary Education Union
