The
Hikurangi Trench (also called the
Hikurangi Trough) is a linear deep in the
Pacific OceanThe Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and...
off the east coast of the
North IslandThe North Island is one of the two main islands of New Zealand, separated from the South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...
of
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous smaller islands, most notably Stewart Island/Rakiura and the Chatham Islands. The indigenous Māori named New Zealand Aotearoa, commonly translated as The Land of the Long White Cloud...
, lying between the southern end of the
Cook StraitCook Strait is the strait between the North and South Islands of New Zealand. It connects the Tasman Sea on the west with the South Pacific Ocean on the east....
and the
Chatham RiseThe Chatham Rise is an area of ocean floor to the east of New Zealand, forming part of the Zealandia continent. It stretches for some 1000 kilometres from near the South Island in the west, to the Chatham Islands in the east...
. Though much shallower, it is the southward continuation of the
Kermadec TrenchThe Kermadec trench is one of Earth's deepest oceanic trenches, reaching a depth of 10,047 m. Formed by the subduction of the Pacific Plate under the Indo-Australian Plate, it runs over a thousand kilometres parallel with and to the east of the Kermadec Ridge and island arc, from near the...
and forms part of the
Kermadec-Tonga Subduction ZoneThe Kermadec-Tonga Subduction Zone is a convergent plate boundary which stretches from the North Island of New Zealand northward, and includes the Hikurangi Trough, the Kermadec Trench and the Tonga Trench...
. It represents the part of the
subductionIn geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. A subduction zone is an area on Earth where two tectonic plates move towards one another and...
zone where the thick oceanic
Hikurangi PlateauHikurangi Plateau is an Early Cretaceous basaltic oceanic plateau in the southwestern Pacific Ocean. The portion of the plateau exposed on the seafloor has an area of 350,000 km2, and including the portions subducted portions beneath the...
is subducting beneath
continental crustThe continental crust is the layer of igneous, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial due to more felsic, or granitic, bulk composition, which lies in...
of the
Indo-Australian PlateThe Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and surrounding ocean, and extends northwest to include the Indian subcontinent and adjacent waters...
. By contrast, the Kermadec and
Tonga TrenchThe Tonga Trench is located in the Pacific Ocean and is 10,882 meters deep at its deepest point, known as the Horizon Deep.The trench lies at the northern end of the Kermadec-Tonga Subduction Zone, an active subduction zone where the Pacific Plate is being subducted below the Tonga Plate and the...
es represent the parts of the subduction zone where
oceanic crustOceanic crust is the part of Earth's lithosphere that surfaces in the ocean basins. Oceanic crust is primarily composed of mafic rocks, or sima...
of the
Pacific PlateThe Pacific Plate is an oceanic tectonic plate beneath the Pacific Ocean.The north-eastern side is a divergent boundary with the Explorer Plate, the Juan de Fuca Plate and the Gorda Plate forming respectively the Explorer Ridge, the Juan de Fuca Ridge and the Gorda Ridge...
is subducting beneath oceanic crust of the Indo-Australian Plate.
Although shallower than the trenches north of it, the Hikurangi Trench reaches depths of 3,000 metres as close as 80 kilometres from shore.
At the southern end of the trench, off the coast of
Marlborough, New ZealandMarlborough is one of the regions of New Zealand, located in the northeast of the South Island. Marlborough is a unitary authority, both a region and a district, and its council is located at Blenheim. Marlborough is known for its dry climate, the picturesque Marlborough Sounds, and Sauvignon blanc...
, the seabed rises sharply, and because of the prevailing winds and tides in this area, many deep water species are found close to the shore.
The
Hikurangi Trench (also called the
Hikurangi Trough) is a linear deep in the
Pacific OceanThe Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and...
off the east coast of the
North IslandThe North Island is one of the two main islands of New Zealand, separated from the South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...
of
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous smaller islands, most notably Stewart Island/Rakiura and the Chatham Islands. The indigenous Māori named New Zealand Aotearoa, commonly translated as The Land of the Long White Cloud...
, lying between the southern end of the
Cook StraitCook Strait is the strait between the North and South Islands of New Zealand. It connects the Tasman Sea on the west with the South Pacific Ocean on the east....
and the
Chatham RiseThe Chatham Rise is an area of ocean floor to the east of New Zealand, forming part of the Zealandia continent. It stretches for some 1000 kilometres from near the South Island in the west, to the Chatham Islands in the east...
. Though much shallower, it is the southward continuation of the
Kermadec TrenchThe Kermadec trench is one of Earth's deepest oceanic trenches, reaching a depth of 10,047 m. Formed by the subduction of the Pacific Plate under the Indo-Australian Plate, it runs over a thousand kilometres parallel with and to the east of the Kermadec Ridge and island arc, from near the...
and forms part of the
Kermadec-Tonga Subduction ZoneThe Kermadec-Tonga Subduction Zone is a convergent plate boundary which stretches from the North Island of New Zealand northward, and includes the Hikurangi Trough, the Kermadec Trench and the Tonga Trench...
. It represents the part of the
subductionIn geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. A subduction zone is an area on Earth where two tectonic plates move towards one another and...
zone where the thick oceanic
Hikurangi PlateauHikurangi Plateau is an Early Cretaceous basaltic oceanic plateau in the southwestern Pacific Ocean. The portion of the plateau exposed on the seafloor has an area of 350,000 km2, and including the portions subducted portions beneath the...
is subducting beneath
continental crustThe continental crust is the layer of igneous, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial due to more felsic, or granitic, bulk composition, which lies in...
of the
Indo-Australian PlateThe Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and surrounding ocean, and extends northwest to include the Indian subcontinent and adjacent waters...
. By contrast, the Kermadec and
Tonga TrenchThe Tonga Trench is located in the Pacific Ocean and is 10,882 meters deep at its deepest point, known as the Horizon Deep.The trench lies at the northern end of the Kermadec-Tonga Subduction Zone, an active subduction zone where the Pacific Plate is being subducted below the Tonga Plate and the...
es represent the parts of the subduction zone where
oceanic crustOceanic crust is the part of Earth's lithosphere that surfaces in the ocean basins. Oceanic crust is primarily composed of mafic rocks, or sima...
of the
Pacific PlateThe Pacific Plate is an oceanic tectonic plate beneath the Pacific Ocean.The north-eastern side is a divergent boundary with the Explorer Plate, the Juan de Fuca Plate and the Gorda Plate forming respectively the Explorer Ridge, the Juan de Fuca Ridge and the Gorda Ridge...
is subducting beneath oceanic crust of the Indo-Australian Plate.
Although shallower than the trenches north of it, the Hikurangi Trench reaches depths of 3,000 metres as close as 80 kilometres from shore.
At the southern end of the trench, off the coast of
Marlborough, New ZealandMarlborough is one of the regions of New Zealand, located in the northeast of the South Island. Marlborough is a unitary authority, both a region and a district, and its council is located at Blenheim. Marlborough is known for its dry climate, the picturesque Marlborough Sounds, and Sauvignon blanc...
, the seabed rises sharply, and because of the prevailing winds and tides in this area, many deep water species are found close to the shore. This food source attracts the whales for which the town of
KaikouraKaikoura is a town on the east coast of the South Island of New Zealand. It is located on State Highway 1 180 km north of Christchurch.Kaikoura became the first local authority to reach the Green Globe tourism certification standard....
is famous.
The plate boundary continues inland along the
Hope FaultThe Hope Fault is a right-lateral transpressional fault in the South Island of New Zealand. It extends northeast from the Alpine Fault on the West Coast to the Pacific Ocean near Kaikoura on the islands East Coast....
. Here the plates converge much more obliquely, exhibiting
transpressionTranspression is a geological term used to describe a region of the Earth's crust that experiences strike-slip shear and a component of shortening, resulting in oblique shear. Transpression typically occurs at a regional scale, such as plate boundaries that have an oblique convergence. More...
instead of subduction.