Geology Of The Taranaki Area

Townsend, D.B.; Vonk, A.; Kamp, P.J.J. (comps) 2008
Geology of the Taranaki area. Lower Hutt: GNS Science. Institute of Geological & Nuclear Sciences 1:250,000 geological map 7
77 p. + 1 folded map

Abstract

The Taranaki 1:250,000 geological map covers a vast area, including:

• Taranaki Peninsula
• Southern King Country
• Wanganui and northern Manawatu areas
• The western part of the Central North Island volcanic plateau

Key Geological Features

• Basement rocks are exposed only in a small area in the northeast.
• Most of the map area is underlain by Neogene sedimentary rocks or Quaternary volcanic and volcaniclastic rocks.
• Dominating the landscape are andesite stratovolcanoes:
  • Egmont Volcanic Centre in the west
  • Ruapehu Volcanic Centre in the east

Coastal and Offshore Features

• Well-preserved flights of middle to late Quaternary marine terraces border much of the coastline.
• Extensive dune fields overlay some of these terraces.
• The Sugar Loaf Islands, located offshore from New Plymouth, are the only offshore islands within the map area.

Volcanic Centres

Egmont Volcanic Centre

Located on the Taranaki Peninsula, this centre includes:

• Severely eroded formations such as Sugar Loaf Islands and Paritutu (c. 1.8 Ma)
• Kaitake (c. 600 ka), Pouakai (c. 250 ka), and Egmont (<130 ka)
• Young satellite vents and cumulodomes

The last known eruption from Egmont Volcano occurred in 1755 AD.

Tongariro Volcanic Centre

The mapped portion includes:

• Ruapehu Group andesite lavas, the oldest dating back to c. 250 ka
• Several other andesitic satellite vents dating back to c. 1.2 Ma

The last eruption of Mt Ruapehu was in 2007.

(auth/DG)