Coastal Restoration Trust of New Zealand

Coastal Dune Ecosystem Reference Database

3-D Stratigraphic models of a composite barrier system, northern New Zealand

Author
Dougherty, A.J.; Nichol, S.L.
Year
2007
Journal / Source
Journal of Coastal Research
Volume
SI 50 (Proceedings of the 9th International Coastal Symposium)
Pages
922 - 926
Summary
This paper presents for the first time, detailed three-dimensional stratigraphic models of both the Holocene and Pleistocene components of a double barrier using ground-penetrating radar. The study focuses on a composite Quaternary barrier system located in Bream Bay, north-east North Island, New Zealand. This coastal compartment maintains a mesotidal environment with low to moderate wave energy. The Holocene barrier has prograded over the last 6500 years during a relative sea-level still stand, or at most 2 metre fall, resulting in a hummocky dune morphology. In contrast, the Pleistocene barrier was formed during rapid sea-level fall towards the end of the Last Interglacial (oxygen isotope 5e to 5a), which resulted in a forced regression producing linear beach ridges.