Tephras form key stratigraphic markers because they can link disparate records in both the terrestrial and marine environments.

Alan Hogg has been involved in dating key New Zealand tephras for many years, by Bayesian methods, including 14C wiggle matching the archaeologically important Kaharoa (AD 1314 ± 12) and Taupo (AD 232 ± 5) tephras.  Recent studies have also centred upon the widespread Kawakawa/Oruanui (25,360 ± 160 cal yr BP), and Rotoehu (44,800 ± 300 - 47,500 ± 2100 cal BP) tephras.

Waikato's Radiocarbon Dating Research

Distribution of Taupo eruption ignimbrite and tephra-fall deposits. The location of the Pureora buried forest containing logs used for dating is shown in the map on the right.

Related research projects:

Selected publications:

  • Vandergoes, MJ, AG Hogg, DJ Lowe, RM Newnham, GH Denton, J Southon, DJA Barrell, M Blaauw, CJN Wilson, MS McGlone,  A Allan, PC Almond , F Petchey, K Dabell, AC Dieffenbacher-Kral, 2013. A revised age for the Kawakawa/Oruanui tephra, a key marker for the Last Glacial Maximum in New Zealand. Quaternary Science Reviews 74:195-201.
  • Lowe DJ, M Blaauw, AG Hogg, RM Newnham, 2013. Ages of 24 widespread tephras erupted since 30,000 years ago in New Zealand, with re-evaluation of the timing and palaeoclimatic implications of the Lateglacial cool episode recorded at Kaipo bog. Quaternary Science Reviews, 74:170-194.
  • Danisik M, P Shane, AK Schmitt, A Hogg, G Santos, S Storm, N Evans, LK Fifield, J Lindsay, 2012.Re-anchoring the late Pleistocene tephrochronology of north island (New Zealand) based on concordant radiocarbon ages and combined 238U/230Th disequilibrium and (U–Th)/He zircon ages. Earth and Planetary Science Letters 349-350:240-250.
  • Hogg A, D Lowe, J Palmer, G Boswijk, C Ramsey, 2012. Definitive high-precision calendar date for the Taupo eruption derived by 14C wiggle-match dating using a New Zealand kauri-derived 14C calibration curve. The Holocene, 22(4):439-449.
  • Holt, KA, DJ Lowe, AG Hogg, RC Wallace, 2011. Distal occurrence of mid-Holocene Whakatane Tephra on the Chatham Islands, New Zealand, and potential for cryptotephra studies. Quaternary International, 246:344-351.
  • Lowe, D, C Wilson, R Newnham, A Hogg, 2010. Dating the Kawakawa/Oruanui eruption: comment on “Optical luminescence dating of a loess section containing a critical tephra marker horizon, SW North Island of NZ” By R. Grapes et al. Quaternary Geochronology. Quaternary Geochronology 5:493-496.