The geology of Auckland varies markedly across the city although Mesozoic greywacke basement underlies throughout, exposed in the Hunua Ranges and some Hauraki Gulf islands. Overlying Miocene and older sedimentary rock is exposed in the central isthmus and North Shore, with Miocene andesite-dominated volcanic rocks in the Waitakere Ranges. Quaternary basalt volcanoes and deposits feature in southern Auckland, and younger volcanoes and deposits are prevalent in central Auckland. Low-lying areas, particularly South Auckland, are covered in Quaternary sediments.
Maps and Information
The Auckland urban and urban fringe areas are part of a current geological mapping initiative. An updated geological map of the South Auckland (Pukekohe) area is the first in a series of maps being developed/produced for the Auckland region.
2022: Pukekohe Geological Map Product
The Pukekohe geological map product includes a geological map with an explanatory text, a geomorphological map and a 3D geological model with an explanatory text.
3D geological model
The 3D geological model provides a generalised representation of the subsurface geology extending from the southern shoreline of Manukau Harbour to the lower Waikato River valley. The main features of this 3D geological model include a representation of the underlying block-faulted Mesozoic basement and basin geometry of the Pukekohe area, contacts and thicknesses of the Te Kuiti Group, Māui Supergroup (Waitematā/Waitākere groups), Ōtāhuhu Member (Takaanini Formation) and ‘undifferentiated Kaihu group’ with a depiction of the South Auckland Volcanic Field strata (Kerikeri Volcanic Group).
The 3D geological model is available and viewable using freely downloadable Leapfrog Viewer(external link) 3D visualisation software or as 2D and 3D surfaces viewable using other 3D modelling and GIS software. These data can be downloaded from links included in the metadata(external link) associated with the Pukekohe 3D Geological Model. The explanatory text(external link) for the 3D geological model can be downloaded from the GNS Online Shop.
2001/2018: QMAP 1:250 000 geological map
For wider and more generalised geological context of the Auckland area, a 1:250 000 geological map was printed with accompanying explanatory text. Digital GIS and image versions of the map are available on DVD. The digital version has since been updated in a national GIS dataset at that nominal scale. The underlying GIS datasets have rich feature attributes.
- Edbrooke, S.E. (compiler) 2001. Geology of the Auckland area(external link). Institute of Geological & Nuclear Sciences 1:250 000 geological map 3. Lower Hutt, New Zealand. Institute of Geological & Nuclear Sciences Limited. 1 sheet + 74 p.
- Heron, D.W. (custodian) 2018. Geological Map of New Zealand 1:250 000(external link). GNS Science geological map 1 (2nd edition). Lower Hutt, New Zealand. GNS Science.
A geological map image can be downloaded(external link) or interrogated through the geological map application(external link). For GIS users, the QMAP geological feature layers can be downloaded from GNS Science’s Web Map/Feature Service(external link).
1992: Geology of the Auckland Urban Area
The central city parts of Auckland are covered by a 1:50000 geological map. The map was subsequently digitised into a GIS dataset in the late 1990s although the accompanying feature attributes are comparatively sparse compared with the later QMAP regional geological mapping.
- Kermode, L.O. 1992. Geology of the Auckland urban area: sheet R11(external link). Scale 1:50 000. Institute of Geological & Nuclear Sciences geological map 2. Institute of Geological & Nuclear Sciences, Lower Hutt. 1 map + 63 p.
1976-1989: 1:63 360 geological maps
These are printed maps with limited accompanying text and there are no digital equivalents.
1989: Geology of the northern Auckland area (out of print)
- Schofield, J.C. 1989. Geological map of New Zealand 1:50,000 Sheets Q10 & R10 Helensville and Whangaparaoa. Lower Hutt: New Zealand Geological Survey. Geological map of New Zealand 1:50,000 Q10 & R10. 2 folded maps + 1 booklet.
1983: Geology of western Auckland area(external link)
- Hayward, B.W. 1983. Geological map of New Zealand 1:50,000 Sheet Q11 Waitakere. Lower Hutt: New Zealand Geological Survey. Geological map of New Zealand 1:50,000 Q11. 1 folded map + 1 booklet.
1976: Geology of the eastern Auckland area(external link)
- Schofield, J.C. 1976. Geological map of New Zealand 1:63,360 Sheet N48 Mangatawhiri. 1st ed. Wellington: Department of Scientific and Industrial Research. Geological map of New Zealand 1:63,360 N48. 1 folded map + booklet.
For GIS users, the layer NZL-Urban Auckland geological units based on an unpublished c. 2012 GNS Science compilation of the 1:50 000 and other unpublished maps can be downloaded from GNS Science’s Web Map Service(external link).
The 3D geological model(external link) is available and viewable using freely downloadable Leapfrog Viewer(external link) 3D visualisation software or as 2D(external link) and 3D(external link) surfaces viewable using other 3D modelling and GIS software. The explanatory text(external link) for the 3D geological model can be downloaded from the GNS Online Shop.