Kermadec Trench

Kermadec
Trench

Fiji

  Lau
Basin

    Tonga-
Kermadec
  Ridge

   Lau-
Colville
  Ridge

Tonga
Trench

Osbourn Trough

Louisville

Seamount

Chain

Hikurangi

Trough

New Zealand

The major geological relationships of the Kermadec Trench (violet) which extends south as a continuation of the Tonga Trench (violet) from the Osbourn Trough to the Hikurangi Trough. Blue represents ocean depths of a kilometer or so and brown shades are shallower. Land is shown in dark green and the black line delineates the continent of Zealandia.

The Kermadec Trench is a linear ocean trench in the south Pacific Ocean. It stretches about 1,000 km (620 mi) from the Louisville Seamount Chain in the north (26°S) to the Hikurangi Plateau in the south (37°S), north-east of New Zealand's North Island.^[1] Together with the Tonga Trench to the north, it forms the 2,000 km (1,200 mi)-long, near-linear Kermadec-Tonga subduction system, which began to evolve in the Eocene when the Pacific Plate started to subduct beneath the Australian Plate. Convergence rates along this subduction system are among the fastest on Earth, 80 mm (3.1 in)/yr in the north and 45 mm (1.8 in)/yr in the south.^[2]