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1847 Zenkoji Earthquake
The occurred at about 21:30 local time on 8 May at Nagano, Japan. It had a magnitude of 7.4 on the surface-wave magnitude scale. It caused the destruction of many houses in Nagano and at least 8,600 people were killed. The earthquake triggered many landslides, the largest of which dammed the Sai River (a tributary of the Shinano River). 19 days later, the failure of this earthquake dam caused a flood that destroyed many more houses and killed 35 people. Tectonic setting During the middle of the Miocene period Japan was affected by the opening of the Sea of Japan as a back-arc basin in response to continuing subduction of the Pacific plate. This period of extensional tectonics caused the development of rift basins on the western side of Honshu, including the northern part of the Fossa Magna. When the back-arc spreading stopped during the late Miocene, the rifted area started to shorten and the basins became inverted. The western margin of the Nagano Basin, part of the Fossa Magn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peak Ground Acceleration
Peak ground acceleration (PGA) is equal to the maximum ground acceleration that occurred during earthquake shaking at a location. PGA is equal to the amplitude of the largest absolute acceleration recorded on an wikt:accelerogram, accelerogram at a site during a particular earthquake. Earthquake shaking generally occurs in all three directions. Therefore, PGA is often split into the horizontal and vertical components. Horizontal PGAs are generally larger than those in the vertical direction but this is not always true, especially close to large earthquakes. PGA is an important parameter (also known as an intensity measure) for earthquake engineering, The design basis earthquake ground motion (DBEGM) is often defined in terms of PGA. Unlike the Richter magnitude scale, Richter and Moment magnitude scale, moment magnitude scales, it is not a measure of the total seismic scales#Magnitude and intensity, energy (magnitude, or size) of an earthquake, but rather of how much the earth shake ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossa Magna
Fossa Magna is a great rift lowland in Japan. It is often confused with the Itoigawa-Shizuoka Tectonic Line. However, Itoigawa-Shizuoka Tectonic Line is a line; Fossa Magna is an area. Fossa Magna is Latin for "great crevasse". This name was given by Heinrich Edmund Naumann. Fossa Magna Museum Fossa Magna Museum is a museum that is located in Itoigawa, Niigata Prefecture. It opened on April 25, 1994. It is part of Itoigawa UNESCO Global Geopark. Itoigawa is located directly above Itoigawa-Shizuoka Tectonic Line and is a place where you can observe a wide variety of rocks, minerals, geological structures and so on. The Fossa Magna Park, a geopark A geopark is a protected area with internationally significant geology within which Sustainability, sustainable development is sought and which includes tourism, conservation, education and research concerning not just geology but other relevant s ..., is also located in Itoigawa. References Landforms of Japan Geology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landslides In Japan
Landslides, also known as landslips, rockslips or rockslides, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, mudflows, shallow or deep-seated slope failures 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 heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Landslides are frequently made worse by human development (such as urban sprawl) and resource exploitation (such as mining and deforestation). Land degradation freque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquakes In The Empire Of Japan
An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume. In its most general sense, the word ''earthquake'' is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as mining, fracking, and nuclear weapons testing. The initial point of rupture is called the hypocenter or focus, while the ground level directly above it is the epicen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nagano (city)
is the capital and largest Cities of Japan, city of Nagano Prefecture, located in the Nagano Basin (Zenkoji Daira) in the central Chūbu region of Japan. Nagano is categorized as a Core cities of Japan, core city of Japan. Nagano City is the highest prefectural capital in Japan, with an altitude of . The city is surrounded by mountains, the highest of which is Mount Takatsuma (2,353 m), and it is near the confluence of the Chikuma River—the longest and widest river in Japan—and the Sai River. , the city had an estimated population of 365,296 in 160,625 households, and a population density of 438 persons per km². The total area of the city is . Overview Nagano City, located in the former Shinano Province, developed in the Nara period (AD 710 to 794) as a temple town (''monzen machi''). The city of Nagano is home to Zenkō-ji, a 7th-century Buddhism, Buddhist temple that is listed as a National Treasure (Japan), Japanese National Treasure. Zenkō-ji was established at its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
May 1847
May is the fifth month of the year in the Julian and Gregorian calendars. Its length is 31 days. May is a month of spring in the Northern Hemisphere, and autumn in the Southern Hemisphere. Therefore, May in the Southern Hemisphere is the seasonal equivalent of November in the Northern Hemisphere and vice versa. Late May typically marks the start of the summer vacation season in the United States (Memorial Day) and Canada (Victoria Day) that ends on Labor Day, the first Monday of September. May (in Latin, ''Maius'') was named for the Greek goddess Maia, who was identified with the Roman era goddess of fertility, Bona Dea, whose festival was held in May. Conversely, the Roman poet Ovid provides a second etymology, in which he says that the month of May is named for the ''maiores,'' Latin for "elders", and that the following month (June) is named for the ''iuniores,'' or "young people" (''Fasti VI.88''). Eta Aquariids meteor shower appears in May. It is visible from about A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1847 In Japan
Events January–March * January 4 – Samuel Colt sells his first revolver pistol to the U.S. government. * January 13 – The Treaty of Cahuenga ends fighting in the Mexican–American War in California. * January 16 – John C. Frémont is appointed Governor of the new California Territory. * January 17 – St. Anthony Hall fraternity is founded at Columbia University, New York City. * January 30 – Yerba Buena, California, is renamed San Francisco. * February 5 – A rescue effort, called the First Relief, leaves Johnson's Ranch to save the ill-fated Donner Party of California-bound migrants who became snowbound in the Sierra Nevada earlier this winter. Some have resorted to survival by cannibalism. * February 22 – Mexican–American War: Battle of Buena Vista – 5,000 American troops under General Zachary Taylor use their superiority in artillery to drive off 15,000 Mexican troops under Antonio López de Santa Anna, defeating the Mexicans the next day. * Februar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1847 Earthquakes
Events January–March * January 4 – Samuel Colt sells his first revolver pistol to the U.S. government. * January 13 – The Treaty of Cahuenga ends fighting in the Mexican–American War in California. * January 16 – John C. Frémont is appointed Governor of the new California Territory. * January 17 – St. Anthony Hall fraternity is founded at Columbia University, New York City. * January 30 – Yerba Buena, California, is renamed San Francisco. * February 5 – A rescue effort, called the First Relief, leaves Johnson's Ranch to save the ill-fated Donner Party of California-bound migrants who became snowbound in the Sierra Nevada earlier this winter. Some have resorted to survival by cannibalism. * February 22 – Mexican–American War: Battle of Buena Vista – 5,000 American troops under General Zachary Taylor use their superiority in artillery to drive off 15,000 Mexican troops under Antonio López de Santa Anna, defeating the Mexicans the next day. * Februa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the Plane (geometry), plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Fault
An active fault is a fault that is likely to become the source of another earthquake sometime in the future. Geologists commonly consider faults to be active if there has been movement observed or evidence of seismic activity during the last 10,000 years. * Active faulting is considered to be a geologic hazard – one related to earthquakes as a cause. Effects of movement on an active fault include strong ground motion, surface faulting, tectonic deformation, landslides and rockfalls, liquefaction, tsunamis, and seiches. Quaternary faults are those active faults that have been recognized at the surface and which have evidence of movement during the Quaternary Period. Related geological disciplines for ''active-fault'' studies include geomorphology, seismology, reflection seismology, plate tectonics, geodetics and remote sensing, risk analysis, and others. Location Active faults tend to occur in the vicinity of tectonic plate boundaries, and active fault research h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inversion (geology)
In structural geology, inversion or basin inversion relates to the relative uplift of a sedimentary basin or as a result of crustal shortening. This normally excludes uplift developed in the footwalls of later extensional faults, or uplift caused by mantle plumes. "Inversion" can also refer to individual faults, where an extensional fault is reactivated in the opposite direction to its original movement. The term ''negative inversion'' is also occasionally used to describe the reactivation of reverse faults and thrusts during extension. The term "inversion" simply refers to the fact that a relatively low-lying area is uplifted – the rock sequence itself is not normally inverted. Formation Many inversion structures are caused by the direct reactivation of pre-existing extensional faults. In some cases only the deeper parts of the fault are reactivated and the shortening is accommodated over a much broader area in the shallow part of the section. The existing fault ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
