The Amurian Plate (or Amur Plate; also occasionally referred to as the China Plate) is a minor tectonic plate in the northern and eastern hemispheres. It covers Manchuria, the Korean Peninsula, the Yellow Sea, and Primorsky Krai. Once thought to be a part of the Eurasian Plate, the Amur Plate is now generally considered to be a separate plate moving southeast with respect to the Eurasian Plate. The Amurian Plate is named after the Amur River, that forms the border between the Russian Far East and Northeastern China. It is bounded on the north, west, and southwest by the Eurasian Plate, on the east by the Okhotsk Plate, to the southeast by the Philippine Sea Plate along the Suruga Trough and the Nankai Trough, and the Okinawa Plate, and the Yangtze Plate.
The Baikal Rift Zone is considered a boundary between the Amurian Plate and the Eurasian Plate. GPS measurements indicate that the plate is slowly rotating counterclockwise.
The Amurian Plate may have been involved in the 1976 Tangshan earthquake in China.
|Features||Korea, Manchuria, Lake Baikal|
|1Relative to the African Plate|
The 1995 Neftegorsk earthquake occurred on 28 May at 1:04 local time on northern Sakhalin Island in the Russian Far East. It was the most destructive earthquake known within the current territory of Russia, with a magnitude of Ms 7.1 and maximum Mercalli intensity of IX (Violent) that devastated the oil town of Neftegorsk, where 2,040 of its 3,977 citizens were killed, and another 750 injured.90% of the victims were killed by the collapse of 17 five-story residential buildings. While Western media generally attributed the collapses to allegedly poor construction and shoddy materials of Soviet-era construction, a geotechnical study faulted a failure to accommodate the possibility of soil liquefaction in an area that was considered "practically aseismic".The Belgian Centre for Research on the Epidemiology of Disasters' EM-DAT database places the total damage at $64.1 million, while the United States' National Geophysical Data Center assesses the damage at $300 million.
This quake was not only catastrophic, it was totally unexpected: earthquakes with magnitudes greater than 6 were not known to occur in the area of northern Sakhalin Island. It is also of great scientific interest (some 20 papers have been published) because it occurred near a poorly known tectonic plate boundary where the Okhotsk Plate (connected with North American Plate) is crashing into the Amurian Plate (part of the Eurasian Plate), and indicates that the plate boundary is associated with a north-south striking seismic belt that runs the length of Sakhalin. More precisely, this earthquake occurred on the Upper Piltoun fault (also known as the Gyrgylan'i—Ossoy fault), which branches off the main Sakhalin-Hokkaido fault that runs along the east side of the island.35 km (22 mi) of surface rupturing was observed (46 km including a branching fault), with an estimated average lateral displacement of about 4 meters, but up to 8 m (9 yd) in some places. (This compares to 14 km of slip estimated to have accumulated on the Sakhalin-Hokkaido fault in the last 4 million years.) The unusual strength of this quake and length of rupturing, and the low level of seismic activity beforehand, has been attributed to the accumulation of strain over a long period of time on a locked fault segment.Eurasian Plate
The Eurasian Plate is a tectonic plate which includes most of the continent of Eurasia (a landmass consisting of the traditional continents of Europe and Asia), with the notable exceptions of the Indian subcontinent, the Arabian subcontinent, and the area east of the Chersky Range in East Siberia. It also includes oceanic crust extending westward to the Mid-Atlantic Ridge and northward to the Gakkel Ridge.
The eastern side is a boundary with the North American Plate to the north and a boundary with the Philippine Sea Plate to the south and possibly with the Okhotsk Plate and the Amurian Plate. The southerly side is a boundary with the African Plate to the west, the Arabian Plate in the middle and the Indo-Australian Plate to the east. The westerly side is a divergent boundary with the North American Plate forming the northernmost part of the Mid-Atlantic Ridge, which is straddled by Iceland. All of the volcanic eruptions in Iceland, such as the 1973 eruption of Eldfell, the 1783 eruption of Laki, and the 2010 eruption of Eyjafjallajökull, are caused by the North American and the Eurasian Plates moving apart, which is a result of divergent plate boundary forces.
The geodynamics of central Asia is dominated by the interaction between the Eurasian and Indian Plates. In this area, many subplates or crust blocks have been recognized, which form the Central Asian and the East Asian transit zones.Geography of Japan
Japan is an island country comprising a stratovolcanic archipelago over 3,000 km (1,900 mi) along East Asia's Pacific coast. It consists of 6,852 islands. The 5 main islands are Hokkaido, Honshu, Kyushu, Shikoku and Okinawa. There are 6,847 'remote islands'. The Ryukyu Islands and Nanpō Islands are south and east of the main islands.
The territory extends 377,973.89 km2 (145,936.53 sq mi). It is the 4th largest island country in the world and the largest island country in East Asia. Japan has the sixth longest coastline 29,751 km (18,486 mi) and the eighth largest Exclusive Economic Zone of 4,470,000 km2 (1,730,000 sq mi) in the world.The terrain is mostly rugged and mountainous with 66% forest. The population is clustered in urban areas on the coast, plains and valleys. Japan is located in the northwestern Ring of Fire on multiple tectonic plates. East of the Japanese archipelago are three oceanic trenches. The Japan Trench is created as the oceanic Pacific Plate subducts beneath the continental Okhotsk Plate. The continuous subduction process causes frequent earthquakes, tsunami and stratovolcanoes. The islands are also affected by typhoons. The subduction plates have pulled the Japanese archipelago eastward, created the Sea of Japan and separated it from the Asian continent by back-arc spreading 15 million years ago.The climate of the Japanese archipelago varies from humid continental in the north (Hokkaido) to humid subtropical and tropical rainforest in the south (Okinawa Prefecture). These differences in climate and landscape have allowed the development of a diverse flora and fauna, with some rare endemic species, especially in the Ogasawara Islands.
Japan extends from 20° to 45° north latitude (Okinotorishima to Benten-jima) and from 122° to 153° east longitude (Yonaguni to Minami Torishima). Japan is surrounded by seas. To the north the Sea of Okhotsk separates it from the Russian Far East, to the west the Sea of Japan separates it from the Korean Peninsula, to the southwest the East China Sea separates the Ryukyu Islands from China and Taiwan, to the east is the Pacific Ocean.Geology of Japan
The islands of Japan are primarily the result of several large ocean movements occurring over hundreds of millions of years from the mid-Silurian to the Pleistocene as a result of the subduction of the Philippine Sea Plate beneath the continental Amurian Plate and Okinawa Plate to the south, and subduction of the Pacific Plate under the Okhotsk Plate to the north.
Japan was originally attached to the eastern coast of the Eurasian continent. The subducting plates, being deeper than the Eurasian plate, pulled Japan eastward, opening the Sea of Japan around 15 million years ago. The Strait of Tartary and the Korea Strait opened much later.
Japan is situated in a volcanic zone on the Pacific Ring of Fire. Frequent low intensity earth tremors and occasional volcanic activity are felt throughout the islands. Destructive earthquakes, often resulting in tsunamis, occur several times a century. The most recent major quakes include the 2011 Tōhoku earthquake and tsunami, the 2004 Chūetsu earthquake and the Great Hanshin earthquake of 1995. Hot springs are numerous and have been developed as resorts.Geology of North Korea
The geology of North Korea has been studied by the Central Geological Survey of Mineral Resources, rare international research and by inference from South Korea's geology.Geology of the Pacific Ocean
The Pacific Ocean evolved in the Mesozoic from the Panthalassic Ocean, which had formed when Rodinia rifted apart around 750 Ma. The first ocean floor which is part of the current Pacific Plate began 160 Ma to the west of the central Pacific and subsequently developed into the largest oceanic plate on Earth.The tectonic plates continue to move today. The slowest spreading ridge is the Gakkel Ridge on the Arctic Ocean floor, which spreads at less than 2.5 cm/year (1 in/year), while the fastest, the East Pacific Rise near Easter Island, has a spreading rate of over 15 cm/year (6 in/year).Izu Peninsula
The Izu peninsula (伊豆半島, Izu-hantō) is a large mountainous peninsula with deeply indented coasts to the west of Tokyo on the Pacific coast of the island of Honshū, Japan. Formerly the eponymous Izu Province, Izu peninsula is now a part of Shizuoka Prefecture. The peninsula has an area of 1,421.24 km² and its estimated population in 2005 was 473,942 people. The populated areas primarily lie on the north and east.Japan
Japan (Japanese: 日本, Nippon [ɲippoꜜɴ] (listen) or Nihon [ɲihoꜜɴ] (listen); formally 日本国, Nippon-koku or Nihon-koku, lit. 'State of Japan') is an island country in East Asia. Located in the Pacific Ocean, it lies off the eastern coast of the Asian continent and stretches from the Sea of Okhotsk in the north to the East China Sea and the Philippine Sea in the south.
The kanji that make up Japan's name mean 'sun origin', and it is often called the "Land of the Rising Sun". Japan is the world's 4th largest island country and encompasses about 6,852 islands. The stratovolcanic archipelago has five main islands: Honshu, Hokkaido, Kyushu, Shikoku and Okinawa which make up about 97% percent of Japan's land area. The country is divided into 47 prefectures in eight regions, with Hokkaido being the northernmost prefecture and Okinawa being the southernmost one (albeit, in Japanese culture the country is considered to be divided east to west ). Japan is the 2nd most populous island country. The population of approximately 126 million is the world's eleventh largest, of which 98.5% are ethnic Japanese. 90.7% of people live in cities, while 9.3% live in the countryside. About 13.8 million people live in Tokyo, the capital of Japan. The Greater Tokyo Area is the most populous metropolitan area in the world with over 38 million people.Archaeological research indicates that Japan was inhabited as early as the Upper Paleolithic period. The first written mention of Japan is in Chinese history texts from the 1st century AD. Influence from other regions, mainly China, followed by periods of isolation, particularly from Western Europe, has characterized Japan's history.
From the 12th century until 1868, Japan was ruled in the name of the Emperor by successive feudal military shōguns. Japan entered into a long period of isolation in the early 17th century, which was ended in 1853 when a United States fleet pressured Japan to open to the West. After nearly two decades of internal conflict and insurrection, the Imperial Court regained its political power in 1868 through the help of several clans from Chōshū and Satsuma – and the Empire of Japan was established. In the late 19th and early 20th centuries, victories in the First Sino-Japanese War, the Russo-Japanese War and World War I allowed Japan to expand its empire during a period of increasing militarism. The Second Sino-Japanese War of 1937 expanded into part of World War II in 1941, which came to an end in 1945 following the Japanese surrender. Since adopting its revised constitution on May 3, 1947, during the occupation led by SCAP, the sovereign state of Japan has maintained a unitary parliamentary constitutional monarchy with an Emperor and an elected legislature called the National Diet.
Japan is a member of the ASEAN Plus mechanism, UN, the OECD, the G7, the G8, and the G20, and is considered a great power. Its economy is the world's third-largest by nominal GDP and the fourth-largest by purchasing power parity. It is also the world's fourth-largest exporter and fourth-largest importer.
Japan benefits from a highly skilled and educated workforce; it has among the world's largest proportion of citizens holding a tertiary education degree. Although it has officially renounced its right to declare war, Japan maintains a modern military with the world's eighth-largest military budget, used for self-defense and peacekeeping roles; it ranked as the world's fourth-most powerful military in 2015. Japan is a highly developed country with a very high standard of living and Human Development Index. Its population enjoys one of the highest life expectancy and the third lowest infant mortality rate in the world, but is experiencing issues due to an aging population and low birthrate. As of 2019, Japanese citizens had visa-free or visa-on-arrival access to 189 countries and territories, ranking the Japanese passport 1st in the world, tied with Singapore. Japan is renowned for its striking art, historical and extensive cinema, influential music industry, manga, anime, video gaming, rich cuisine and its major contributions to science and modern technology.List of earthquakes in Japan
This is a list of earthquakes in Japan with either a magnitude greater than or equal to 7.0 or which caused significant damage or casualties. As indicated below, magnitude is measured on the Richter magnitude scale (ML) or the moment magnitude scale (Mw), or the surface wave magnitude scale (Ms) for very old earthquakes. The present list is not exhaustive, and reliable and precise magnitude data is scarce for earthquakes that occurred prior to the development of modern measuring instruments.List of tectonic plates
This is a list of tectonic plates on the Earth's surface. Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. The plates are around 100 km (62 mi) thick and consist of two principal types of material: oceanic crust (also called sima from silicon and magnesium) and continental crust (sial from silicon and aluminium). The composition of the two types of crust differs markedly, with mafic basaltic rocks dominating oceanic crust, while continental crust consists principally of lower-density felsic granitic rocks.Mining in Japan
Mining in Japan is minimal because Japan does not possess many on-shore mineral resources. Many of the on-shore minerals have already been mined to the point that it has become less expensive to import minerals. There are small deposits of coal, oil, iron and minerals in the Japanese archipelago. Japan is scarce in critical natural resources and has been heavily dependent on imported energy and raw materials. There are major deep sea mineral resources in the seabed of Japan. This is not mined yet due to technological obstacles for deep sea mining.Mount Daisen
Mount Daisen (大山, Daisen), is a volcanic mountain in Tottori Prefecture, Japan. It has an elevation of 1,729 metres. This mountain is the highest in the Chūgoku region, and the most important volcano on the Daisen volcanic belt: a part of Southwest Honshu volcanic arc, where the Philippine Sea Plate is subducting under the Amurian Plate.Mount Fuji
Mount Fuji (富士山, Fujisan, IPA: [ɸɯꜜ(d)ʑisaɴ] (listen)), located on Honshū, is the highest volcano in Japan at 3,776.24 m (12,389 ft), 2nd-highest volcano of an island in Asia (after Mount Kerinci in Sumatra), and 7th-highest peak of an island in the world. It is an active stratovolcano that last erupted in 1707–1708. Mount Fuji lies about 100 kilometers (60 mi) south-west of Tokyo, and can be seen from there on a clear day. Mount Fuji's exceptionally symmetrical cone, which is snow-capped for about 5 months a year, is commonly used as a symbol of Japan and it is frequently depicted in art and photographs, as well as visited by sightseers and climbers.Mount Fuji is one of Japan's "Three Holy Mountains" (三霊山, Sanreizan) along with Mount Tate and Mount Haku. It is also a Special Place of Scenic Beauty and one of Japan's Historic Sites. It was added to the World Heritage List as a Cultural Site on June 22, 2013. According to UNESCO, Mount Fuji has "inspired artists and poets and been the object of pilgrimage for centuries". UNESCO recognizes 25 sites of cultural interest within the Mount Fuji locality. These 25 locations include the mountain and the Shinto shrine, Fujisan Hongū Sengen Taisha, as well as the Buddhist Taisekiji Head Temple founded in 1290, later immortalized by Japanese ukiyo-e artist Katsushika Hokusai.Nankai megathrust earthquakes
Nankai megathrust earthquakes are great megathrust earthquakes that occur along the Nankai megathrust – the fault under the Nankai Trough – which forms the plate interface between the subducting Philippine Sea Plate and the overriding Amurian Plate (part of the Eurasian Plate), which dips beneath southwestern Honshu, Japan. The fault is divided into five segments in three zones, which rupture separately or in combination, and depending on location, the resulting earthquakes are subdivided by zone from west to east into Nankai earthquakes, Tōnankai earthquakes, and Tōkai earthquakes.
The earthquakes occur with a return period of about 90–200 years, and often occur in pairs, where a rupture along part of the fault is followed by a rupture elsewhere, notably the 1854 Ansei-Tōkai earthquake and the 1854 Ansei-Nankai earthquake the next day, and the 1944 Tōnankai earthquake, followed by the 1946 Nankaidō earthquake. In one recorded case (the 1707 Hōei earthquake) the fault ruptured along its entire length. All of these great earthquakes have resulted in damaging tsunamis, which are particularly damaging due to the Japanese population being concentrated on the Taiheiyō Belt, especially the coastal cities of Tokyo and Osaka, the two most populous in Japan. The area remains seismically active, and future earthquakes are anticipated, with a high risk of a Nankai earthquake in the near future, which could be potentially very damaging.Okhotsk Plate
The Okhotsk Plate is a minor tectonic plate covering the Sea of Okhotsk, the Kamchatka Peninsula, Sakhalin Island and Tōhoku and Hokkaidō in Japan. It was formerly considered a part of the North American Plate, but recent studies indicate that it is an independent plate, bounded on the north by the North American Plate. The boundary is a left-lateral moving transform fault, the Ulakhan Fault. On the east, the plate is bounded by the Pacific Plate at the Kuril-Kamchatka Trench and the Japan Trench, on the south by the Philippine Sea Plate at the Nankai Trough, on the west by the Eurasian Plate, and possibly on the southwest by the Amurian Plate.Philippine Sea Plate
The Philippine Sea Plate or the Philippine Plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of the Philippine Mobile Belt, which is geologically and tectonically separate from the Philippine Sea Plate.
Philippine Sea plate is bordered mostly by convergent boundaries:
To the north, the Philippine Sea Plate meets the Okhotsk Plate at the Nankai Trough. The Philippine Sea Plate, the Amurian Plate, and the Okhotsk Plate meet at Mount Fuji in Japan. The thickened crust of the Izu-Bonin-Mariana arc colliding with Japan constitutes the Izu Collision Zone.
To the east, Philippine Sea Plate meets the Pacific Plate, subducting at the Izu-Ogasawara Trench. The east of the plate includes the Izu-Ogasawara (Bonin) and the Mariana Islands, forming the Izu-Bonin-Mariana Arc system. There is also a divergent boundary between the Philippine Sea Plate and the small Mariana Plate which carries the Mariana Islands.
To the south, the Philippine Sea Plate is bounded by the Caroline Plate and Bird's Head Plate.
To the west, the Philippine Sea Plate subducts under the Philippine Mobile Belt at the Philippine Trench and the East Luzon Trench. (The adjacent rendition of Prof. Peter Bird's map is inaccurate in this respect.)
To the northwest, the Philippine Sea Plate meets Taiwan and the Nansei islands on the Okinawa Plate, and southern Japan on the Amurian Plate.Suruga Trough
Suruga Trough (駿河トラフ, Suruga Torafu) is a trough that lies off the coast of Suruga Bay in Japan, forming part of the Nankai Trough, the latter being responsible the source of many large earthquakes in Japan's history. Both mark the boundary of the Philippine Sea Plate subducting under the Amurian Plate.Triple junction
A triple junction is the point where the boundaries of three tectonic plates meet. At the triple junction each of the three boundaries will be one of 3 types - a ridge (R), trench (T) or transform fault (F) - and triple junctions can be described according to the types of plate margin that meet at them (e.g. Transform-Transform-Trench, Ridge-Ridge-Ridge, or abbreviated F-F-T, R-R-R). Of the many possible types of triple junction only a few are stable through time ('stable' in this context means that the geometrical configuration of the triple junction will not change through geologic time). The meeting of 4 or more plates is also theoretically possible but junctions will only exist instantaneously.
|Faults and rift zones|
|Trenches and troughs|