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1626 Lingqiu Earthquake
The 1626 Lingqiu earthquake had an epicentre in Lingqiu County, Shanxi Province during the Ming dynasty. The estimated surface wave magnitude () 7.0 earthquake caused many buildings to collapse. Over 5,200 people were killed. Tectonic setting The Shanxi Rift System is a seismically active intra-continental rift zone in North China. Since 231 BC, eight 7.0 earthquakes have occurred along the rift system. The 1303 Hongdong, 1556 Shanxi, and 1695 Linfen earthquakes were the deadliest associated with the rift, with death tolls of 50,000 to 830,000 respectively. Bounded to the west by the Lüliang Mountains, and the east by the Taihang Mountains, the Shanxi Rift forms the eastern boundary of the Ordos Block; a fragment of continental crust within the Eurasian Plate. Within the rift features half-grabens. It formed when extension began in the Miocene or Pliocene, separating the crust into the Ordos Block from the North China Craton. The reason for extension in this part of China is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qing Dynasty
The Qing dynasty ( ), officially the Great Qing,, was a Manchu-led imperial dynasty of China and the last orthodox dynasty in Chinese history. It emerged from the Later Jin dynasty founded by the Jianzhou Jurchens, a Tungusic-speaking ethnic group who unified other Jurchen tribes to form a new "Manchu" ethnic identity. The dynasty was officially proclaimed in 1636 in Manchuria (modern-day Northeast China and Outer Manchuria). It seized control of Beijing in 1644, then later expanded its rule over the whole of China proper and Taiwan, and finally expanded into Inner Asia. The dynasty lasted until 1912 when it was overthrown in the Xinhai Revolution. In orthodox Chinese historiography, the Qing dynasty was preceded by the Ming dynasty and succeeded by the Republic of China. The multiethnic Qing dynasty lasted for almost three centuries and assembled the territorial base for modern China. It was the largest imperial dynasty in the history of China and in 1790 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North China Craton
The North China Craton is a continental crustal block with one of Earth's most complete and complex records of igneous, sedimentary and metamorphic processes. It is located in northeast China, Inner Mongolia, the Yellow Sea, and North Korea. The term craton designates this as a piece of continent that is stable, buoyant and rigid. Basic properties of the cratonic crust include being thick (around 200 km), relatively cold when compared to other regions, and low density. The North China Craton is an ancient craton, which experienced a long period of stability and fitted the definition of a craton well. However, the North China Craton later experienced destruction of some of its deeper parts (decratonization), which means that this piece of continent is no longer as stable. The North China Craton was at first some discrete, separate blocks of continents with independent tectonic activities. In the Paleoproterozoic (2.5-1.8 billion years ago) the continents collided and amalg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault Scarp
A fault scarp is a small step or offset on the ground surface where one side of a fault has moved vertically with respect to the other. It is the topographic expression of faulting attributed to the displacement of the land surface by movement along faults. They are exhibited either by differential movement and subsequent erosion along an old ''inactive'' geologic fault (a sort of old rupture), or by a movement on a recent active fault. Characteristics Fault scarps often contain highly fractured rock of both hard and weak consistency. In many cases, bluffs form from the upthrown block and can be very steep. The height of the scarp formation is equal to the vertical displacement along the fault. Active scarps are usually formed by tectonic displacement, e.g. when an earthquake changes the elevation of the ground and can be caused by any type of fault, including strike-slip faults, whose motion is primarily horizontal. This movement is usually episodic, with the height of the bluf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquake Rupture
In seismology, an earthquake rupture is the extent of slip that occurs during an earthquake in the Earth's crust. Earthquakes occur for many reasons that include: landslides, movement of magma in a volcano, the formation of a new fault, or, most commonly of all, a slip on an existing fault. Nucleation A tectonic earthquake begins by an initial rupture at a point on the fault surface, a process known as nucleation. The scale of the nucleation zone is uncertain, with some evidence, such as the rupture dimensions of the smallest earthquakes, suggesting that it is smaller than 100 m while other evidence, such as a slow component revealed by low-frequency spectra of some earthquakes, suggest that it is larger. The possibility that the nucleation involves some sort of preparation process is supported by the observation that about 40% of earthquakes are preceded by foreshocks. However, some large earthquakes, such as the M8.6 1950 India - China earthquake., have no foreshocks and it r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Rifts
Continental Rifts: Contemporary Time-based Works of Africa was a contemporary art show at UCLA's Fowler Museum The Fowler Museum at UCLA, commonly known as The Fowler, and formerly Museum of Cultural History and Fowler Museum of Cultural History, is a museum on the campus of the University of California, Los Angeles (UCLA) which explores art and material ... held February through June 2009. Bibliography * * * * * External links * Art exhibitions in the United States 2009 in art Art in Greater Los Angeles {{Art-display-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustal Extension
Extensional tectonics is concerned with the structures formed by, and the tectonic processes associated with, the stretching of a planetary body's crust or lithosphere. Deformation styles The types of structure and the geometries formed depend on the amount of stretching involved. Stretching is generally measured using the parameter ''β'', known as the ''beta factor'', where : \beta = \frac \,, ''t''0 is the initial crustal thickness and ''t''1 is the final crustal thickness. It is also the equivalent of the strain parameter ''stretch''. Low beta factor In areas of relatively low crustal stretching, the dominant structures are high to moderate angle normal faults, with associated half grabens and tilted fault blocks. High beta factor In areas of high crustal stretching, individual extensional faults may become rotated to too low a dip to remain active and a new set of faults may be generated. Large displacements may juxtapose syntectonic sediments against metamorphic ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal Fault
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of 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 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 geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 per century. The most recent major quakes include the 2011 Tōhoku earthquake and tsunami, the 2004 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subducts
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the heavier plate dives beneath the second plate and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with the average rate of convergence being approximately two to eight centimeters per year along most plate boundaries. Subduction is possible because the cold oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle underlying the cold, rigid lithosphere. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Plate
The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. At , it is the largest tectonic plate. The plate first came into existence 190 million years ago, at the triple junction between the Farallon, Phoenix, and Izanagi Plates. The Pacific Plate subsequently grew to where it underlies most of the Pacific Ocean basin. This reduced the Farallon Plate to a few remnants along the west coast of North America and the Phoenix Plate to a small remnant near the Drake Passage, and destroyed the Izanagi Plate by subduction under Asia. The Pacific Plate contains an interior hot spot forming the Hawaiian Islands. Boundaries The north-eastern side is a divergent boundary with the Explorer Plate, the Juan de Fuca Plate and the Gorda Plate forming respectively the Explorer Ridge, the Juan de Fuca Ridge and the Gorda Ridge. In the middle of the eastern side is a transform boundary with the North American Plate along the San Andreas Fault, and a boundary w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slab Rollback
Oceanic trenches are prominent long, narrow topographic depressions of the ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers in length. There are about of oceanic trenches worldwide, mostly around the Pacific Ocean, but also in the eastern Indian Ocean and a few other locations. The greatest ocean depth measured is in the Challenger Deep of the Mariana Trench, at a depth of below sea level. Oceanic trenches are a feature of the Earth's distinctive plate tectonics. They mark the locations of convergent plate boundaries, along which lithospheric plates move towards each other at rates that vary from a few millimeters to over ten centimeters per year. Oceanic lithosphere moves into trenches at a global rate of about 3 km2/yr. A trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab. Trenches are generally parallel to and about fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 peaks exceeding in elevation lie in the Himalayas. By contrast, the highest peak outside Asia ( Aconcagua, in the Andes) is tall. The Himalayas abut or cross five countries: Bhutan, India, Nepal, China, and Pakistan. The sovereignty of the range in the Kashmir region is disputed among India, Pakistan, and China. The Himalayan range is bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by the Tibetan Plateau, and on the south by the Indo-Gangetic Plain. Some of the world's major rivers, the Indus, the Ganges, and the Tsangpo– Brahmaputra, rise in the vicinity of the Himalayas, and their combined drainage basin is home to some 600 million people; 53 million people live in the Himalayas. The Himalaya ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
