Middle Eocene c.40Ma

Middle Eocene map

Incipient subduction to the north, and seafloor spreading south of New Zealand. Development of a precursor boundary between Australian and Pacific plates, with propagation of a continental rift through central-western areas. Subdued topography elsewhere. Likely high heat flow in south. Challenger Plateau breached by marine seaway, Campbell Plateau submerged. Deposition of potential petroleum source (green) and reservoir (yellow) rocks.

The present-day 2000 m isobath, which nominally marks the periphery of the New Zealand sub-continent, is used for reference (boundary between dark blue and mid blue). Bold line depicts paleo-coastline.

Colour coding: white = terrestrial non-deposition; green = terrestrial deposition; yellow = marginal marine sand-dominated facies; pale blue-grey = shelf; mid-blue = slope or submarine rise; dark blue = deep ocean. Faults, subduction zones, and seafloor spreading centres shown in red. Pink circles = active volcanism.

Basins depicted include: Taranaki (TB), East Coast (ECB), Canterbury (CB), Great South (GSB), and Western Southland (WS). EB = Emerald Basin, CP = Campbell Plateau.

To view individual maps, click below:

Download animation of all maps deforming in sequence over 65 million years.