
The Kuril–Kamchatka Trench or Kuril Trench (, ''Kurilo-Kamchatskii Zhyolob'') is an
oceanic trench
Oceanic trenches are prominent, long, narrow topography, topographic depression (geology), depressions of the seabed, ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers ...
in the northwest
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...
. It lies off the southeast coast of
Kamchatka
The Kamchatka Peninsula (, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and western coastlines, respectively.
Immediately offshore along the Pacific ...
and parallels the
Kuril Island chain to meet the
Japan Trench
The Japan Trench is an oceanic trench part of the Pacific Ring of Fire off northeast Japan. It extends from the Kuril Islands to the northern end of the Izu Islands, and is at its deepest. It links the Kuril–Kamchatka Trench to the north and ...
east of
Hokkaido
is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...
. It extends from a
triple junction with the
Ulakhan Fault and the
Aleutian Trench
The Aleutian Trench (or Aleutian Trough) is an oceanic trench along a convergent plate boundary which runs along the southern coastline of Alaska and the Aleutian islands. The trench extends for from a triple junction in the west with the Ula ...
near the
Commander Islands
The Commander Islands, Komandorski Islands, or Komandorskie Islands (, ''Komandorskiye ostrova'') are a series of islands in the Russian Far East, a part of the Aleutian Islands, located about east of the Kamchatka Peninsula in the Bering Sea. ...
, Russia, in the northeast, to the intersection with the Japan Trench in the southwest.
[
The trench formed as a result of the ]subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second p ...
zone, which formed in the late Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...
, that created the Kuril island arc
Island arcs are long archipelago, chains of active volcanoes with intense earthquake, seismic activity found along convergent boundary, convergent plate tectonics, tectonic plate boundaries. Most island arcs originate on oceanic crust and have re ...
as well as the Kamchatka volcanic arc. The Pacific plate is being subducted beneath the Okhotsk plate along the trench, resulting in intense volcanism
Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon. It is caused by the presence of a he ...
.
The maximum depth of the trench is reported in peer-reviewed academic papers as 9,600 meters.
Tectonics
At the Kuril–Kamchatka Trench, the Pacific plate is subducting
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second pla ...
beneath the Okhotsk plate, a minor tectonic plate formerly considered to be part of the North American plate. The convergence rate ranges from ≈
An approximation is anything that is intentionally similar but not exactly equal to something else.
Etymology and usage
The word ''approximation'' is derived from Latin ''approximatus'', from ''proximus'' meaning ''very near'' and the prefix ' ...
/yr in the north to ≈/yr at the southern end. Obliquity of convergence increases to the south, where the transpression
In geology, transpression is a type of Strike-slip fault, strike-slip deformation that deviates from simple shear because of a simultaneous component of shortening perpendicular to the fault plane. This movement ends up resulting in oblique shear. ...
al stress is partitioned into trench-normal thrust earthquakes and trench-parallel strike-slip earthquakes. This partitioning results in westward translation of the Kurile forearc relative to the North American plate.
Associated seismicity
Major earthquakes associated with the subduction zone:[Rhea, S., et al., 2010]
Seismicity of the Earth 1900–2007, Kuril-Kamchatka arc and vicinity
U.S. Geological Survey Open-File Report 2010-1083-C, 1 map sheet, scale 1:5,000,000 accessed 25 October 2022
See also
* Kamchatka earthquakes
*Ring of Fire
The Ring of Fire (also known as the Pacific Ring of Fire, the Rim of Fire, the Girdle of Fire or the Circum-Pacific belt) is a tectonic belt of volcanoes and earthquakes.
It is about long and up to about wide, and surrounds most of the Pa ...
References
External links
Kamchatka & Kuril Islands: Regional Map and Introduction
''www.skimountaineer.com'', accessed 25 October 2022
{{DEFAULTSORT:Kuril-Kamchatka Trench
Landforms of Asia
Landforms of the Kuril Islands
Kamchatka Peninsula
Oceanic trenches of the Pacific Ocean
Subduction zones
Landforms of Russia
Landforms of Sakhalin Oblast
Geology of the Russian Far East