Image
In this view of the Horokiwi quarry face, the vehicle at the base provides a sense of scale. The vertical beds consist of hard, fractured greywacke (light grey), which is intersected with thin layers of black argillite. Greywacke is the rock type most commonly used for aggregate in New Zealand.
Using this item
Reference: CN34040/21
by Lloyd Homer
Permission of GNS Science must be obtained before any use of this image.