Kōrero: Geology – overview

Weathered rock (2 o 2)

Weathered rock

This road cutting, on State Highway 6, south of Charleston, reveals an unconformity (time break) between the dark-coloured Brunner Coal Measures and the underlying weathered granitic rocks. In some places the rocks have been so deeply weathered that they now consist of little more than kaolin clay and quartz. Locally the clay has been quarried and processed for use in the production of pottery and ceramic ware.

The unconformity represents the widespread Waipounamu erosion surface, found over many parts of New Zealand about 65–50 million years ago, when the land was reduced to a peneplain. When tectonic activity was renewed in the late Eocene period (40 million years ago), coal measures and other sediments were deposited on top of the peneplain.

Te whakamahi i tēnei tūemi

Private collection
Photograph by Simon Nathan

This item has been provided for private study purposes (such as school projects, family and local history research) and any published reproduction (print or electronic) may infringe copyright law. It is the responsibility of the user of any material to obtain clearance from the copyright holder.

Ngā whakaahua me ngā rauemi katoa o tēnei kōrero

Te tuhi tohutoro mō tēnei whārangi:

Eileen McSaveney and Simon Nathan, 'Geology – overview - New Zealand breaks away from Gondwana', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/photograph/8318/weathered-rock (accessed 28 May 2020)

He kōrero nā Eileen McSaveney and Simon Nathan, i tāngia i te 12 Jun 2006