The Kuril–Kamchatka Trench or Kuril Trench (, Kurilo-Kamchatskii Zhyolob), known in Japan as , is an oceanic trench in the northwest Pacific Ocean. It lies off the southeast coast of Kamchatka and parallels the Kuril Island chain to meet the Japan Trench east of Hokkaido. It extends from a triple junction with the Ulakhan Fault and the Aleutian Trench near the Commander Islands, Russia, in the northeast, to the intersection with the Japan Trench in the southwest.
The trench formed as a result of the subduction zone, which formed in the late Cretaceous, that created the Kuril island arc as well as the Kamchatka volcanic arc. The Pacific plate is being subducted beneath the Okhotsk plate along the trench, resulting in intense volcanism.
The maximum depth of the trench is reported in peer-reviewed academic papers as 9,600 meters.
History The trench was first discovered during an oceanographic and hydrographic survey by the USS Tuscarora, where the ship had detected a depth of 4655 fathoms or 8513 meters in 1874. Due to this recording the trench held the record of the deepest point in the world, beating out the Challenger expedition's recorded depth of 3875 fathoms or 7086 meters in the Mariana Trench, until it was overthrown in the following year by the Mariana Trench which it had just surpassed.
Tectonics
At the Kuril–Kamchatka Trench, the Pacific plate is subducting beneath the Okhotsk plate, a minor tectonic plate formerly considered to be part of the North American plate. The convergence rate ranges from ≈/yr in the north to ≈/yr at the southern end. Obliquity of convergence increases to the south, where the transpressional 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 Date Location Magnitude3 February 1923Kamchatka, Russia13 April 1923Kamchatka, Russia2 March 1933Sanriku-oki, Japan4 November 1952Kamchatka, Russia6 November 1958Kuril Islands, Russia13 October 1963Kuril Islands, Russia4 October 1994Kuril Islands, Russia25 September 2003Hokkaido, Japan15 November 2006Kuril Islands, Russia24 May 2013Sea of Okhotsk18 July 2017Kamchatka, Russia25 March 2020Kamchatka, Russia29 July 2025Kamchatka, Russia
See also Kamchatka earthquakes Ring of Fire
References
External links Kamchatka & Kuril Islands: Regional Map and Introduction, www.skimountaineer.com, accessed 25 October 2022