1984 Otaki Earthquake
The 1984 Nagano earthquake () hit the western part of Nagano Prefecture, Japan on September 14, 1984, at 08:48 local time (September 13, 1984, at 23:48 UTC). Registering a magnitude of 6.3, the earthquake destroyed Otaki (Japanese: 王滝(おうたき)), and triggered major landslides. The earthquake left at least 29 people dead or missing, making it the deadliest earthquake in 1984. Geology Although the epicenter was only deep, no visible fault appeared. The Japan Meteorological Agency estimated that two faults, one long and one long, had ruptured simultaneously. Relation to other earthquakes Seismologists including Akeo Yoshida state that the 1948 Fukui earthquake, a 7.0 earthquake in Gifu Prefecture, a 6.6 earthquake in Gifu Prefecture in 1969, and this earthquake were earthquakes that occurred in a cycle for a little while in the same area. Main shock Since there was no seismometer in the area, the Japan Meteorological Agency made an estimate intensity, '' Shin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Intraplate Earthquake
The term intraplate earthquake refers to a variety of earthquake that occurs ''within the interior'' of a tectonic plate; this stands in contrast to an interplate earthquake, which occurs ''at the boundary'' of a tectonic plate. Intraplate earthquakes are often called "intraslab earthquakes", especially when occurring in microplates. Intraplate earthquakes are relatively rare compared to the more familiar boundary-located interplate earthquakes. Structures far from plate boundaries tend to lack seismic retrofitting, so large intraplate earthquakes can inflict heavy damage. Examples of damaging intraplate earthquakes are the devastating Gujarat earthquake in 2001, the 2012 Indian Ocean earthquakes, the 2017 Puebla earthquake, the 1811–1812 earthquakes in New Madrid, Missouri, and the 1886 earthquake in Charleston, South Carolina. Fault zones within tectonic plates The surface of the Earth is made up of seven primary and eight secondary tectonic plates, plus dozens of tert ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Lake Shizenko
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ic ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Landslides In 1984
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Causes Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This is essentially due to a decrease in the shear strength of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Landslides In Japan
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Causes Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This is essentially due to a decrease in the shear strength of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1984 In Japan
Events in the year 1984 in Japan. Incumbents *Emperor: Hirohito (Emperor Shōwa) *Prime Minister: Yasuhiro Nakasone ( L–Gunma, 2nd term) * Chief Cabinet Secretary: Takao Fujinami (L–Mie) * Chief Justice of the Supreme Court: Jirō Terata * President of the House of Representatives: Kenji Fukunaga (L–Saitama) * President of the House of Councillors: Mutsuo Kimura (L–Okayama) * Diet sessions: 101st (special session opened in December 1983, to August 8), 102nd (regular, December 1 through 1985, June 25) Governors * Aichi Prefecture: Reiji Suzuki *Akita Prefecture: Kikuji Sasaki *Aomori Prefecture: Masaya Kitamura *Chiba Prefecture: Takeshi Numata *Ehime Prefecture: Haruki Shiraishi *Fukui Prefecture: Heidayū Nakagawa *Fukuoka Prefecture: Hachiji Okuda *Fukushima Prefecture: Isao Matsudaira *Gifu Prefecture: Yosuke Uematsu *Gunma Prefecture: Ichiro Shimizu * Hiroshima Prefecture: Toranosuke Takeshita *Hokkaido: Takahiro Yokomichi *Hyogo Prefecture: Tok ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1984 Earthquakes
Events January * January 1 – The Bornean Sultanate of Brunei gains full independence from the United Kingdom, having become a British protectorate in 1888. * January 7 – Brunei becomes the sixth member of the Association of Southeast Asian Nations (ASEAN). * January 10 ** The United States and the Vatican City, Vatican (Holy See) restore full diplomatic relations. ** The Victoria, Seychelles, Victoria Agreement is signed, institutionalising the Indian Ocean Commission. *January 24 – Steve Jobs launches the Macintosh 128K, Macintosh personal computer in the United States. February * February 3 ** Dr. John Buster and the research team at Harbor–UCLA Medical Center announce history's first embryo transfer from one woman to another, resulting in a live birth. ** STS-41-B: Space Shuttle Challenger, Space Shuttle ''Challenger'' is launched on the 10th Space Shuttle mission. * February 7 – Astronauts Bruce McCandless II and Robert L. Stewart make the first untethered spac ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Check Dam
A steel check dam A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, they are an ancient technique dating from the second century A.D. Check dams are typically, though not always, implemented in a system of several dams situated at regular intervals across the area of interest. Function A check dam placed in the ditch, swale, or channel interrupts the flow of water and flattens the gradient of the channel, thereby reducing the velocity. In turn, this obstruction induces infiltration and reduces eroding. They can be used not only to slow flow velocity but also to distribute flows across a swale to avoid preferential paths and guide flows toward vegetation. Although some sedimentation may result behind the dam, check dams do not primarily function as sediment-trapping devices. For instance, on the Grali ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Japan Median Tectonic Line
, also Median Tectonic Line (MTL), is Japan's longest fault system. The MTL begins near Ibaraki Prefecture, where it connects with the Itoigawa-Shizuoka Tectonic Line (ISTL) and the Fossa Magna. It runs parallel to Japan's volcanic arc, passing through central Honshū to near Nagoya, through Mikawa Bay, then through the Inland Sea from the Kii Channel and Naruto Strait to Shikoku along the Sadamisaki Peninsula and the Bungo Channel and Hōyo Strait to Kyūshū. The sense of motion on the MTL is right-lateral strike-slip, at a rate of about 5–10 mm/yr.Okada, A., On the Quaternary faulting along the Median Tectonic Line, in ''Median Tectonic Line'' (in Japanese with English abstract), edited by R. Sugiyama, pp. 49–86, Tokai Univ. Press, Tokyo, 1973. This sense of motion is consistent with the direction of oblique convergence at the Nankai Trough. The rate of motion on the MTL is much less than the rate of convergence at the plate boundary, making it difficult to disti ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Radon
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into various short-lived radioactive elements and lead. Radon itself is the immediate decay product of radium. Its most stable isotope, 222Rn, has a half-life of only 3.8 days, making it one of the rarest elements. Since thorium and uranium are two of the most common radioactive elements on Earth, while also having three isotopes with half-lives on the order of several billion years, radon will be present on Earth long into the future despite its short half-life. The decay of radon produces many other short-lived nuclides, known as "radon daughters", ending at stable isotopes of lead.+ ion is believed to form by the following reaction: : Rn (g) + 2 (s) → (s) + 2 (g) For this reason, antimo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, and highly combustible. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all normal matter.However, most of the universe's mass is not in the form of baryons or chemical elements. See dark matter and dark energy. Stars such as the Sun are mainly composed of hydrogen in the plasma state. Most of the hydrogen on Earth exists in molecular forms such as water and organic compounds. For the most common isotope of hydrogen (symbol 1H) each atom has one proton, one electron, and no neutrons. In the early universe, the formation of protons, the nuclei of hydrogen, occurred during the first second after the Big Bang. The emergence of neutral hydrogen atoms throughout the universe occur ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Argon
Argon is a chemical element with the symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third-most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abundant as water vapor (which averages about 4000 ppmv, but varies greatly), 23 times as abundant as carbon dioxide (400 ppmv), and more than 500 times as abundant as neon (18 ppmv). Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all of the argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in supernovas. The name "argon" is derived from the Greek word , neuter singular form of meaning 'lazy' or 'inactive', as a reference to the fact that the element undergoes almost no chemical reactions. The com ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases. It has also been detected on other ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |