QM3 Auckland

The Auckland 1:250,000 geological map covers 11,800 km2 of the greater Auckland area, parts of southern Northland and northern Waikato, and Coromandel Peninsula, in the north of the North Island, New Zealand. It encompasses the adjacent offshore areas and islands of the Hauraki Gulf, including Great Barrier Island.

The landscape of this region, formed mainly by late Cenozoic block faulting and volcanicity, has four major geomorphic elements.
  1. Mesozoic and Cenozoic highlands form elevated blocks of the Hunua, Hapuakohe and Taupiri ranges in south Auckland and north Waikato, the rolling hill country of north Auckland and west Waikato, and the rugged, well dissected volcanic landscapes of the Coromandel Range, Great Barrier Island and Waitakere Ranges.
  2. Pliocene and Quaternary barrier dune complexes are present along much of the west coast and in the western Bay of Plenty.
  3. Extensive lowland areas infilled with Pliocene and Quaternary sediments include the Lower Waikato and Manukau lowlands, and Hauraki Plains.
  4. Quaternary basalt fields of Auckland and South Auckland form gently rolling surfaces with volcanic cones rising above them. Offshore, the seafloor west of Auckland slopes gently westward for 20-40 km to the shelf edge, where the water depth is about 150 m, then deepens to over 1000 m. The eastern offshore area is characterised by the relatively shallowness.