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2022 Ya'an Earthquake
On June 1, 2022, a moment magnitude () 5.8 or surface-wave magnitude () 6.1 earthquake struck Lushan County in Ya'an, Sichuan Province, China. At least four people were killed and 42 were injured. The earthquake had a maximum intensity of VIII on the China seismic intensity scale, causing damage to many homes and triggering rockslides. Tectonic setting The active plate convergence between the Indian and Eurasian Plates along the Main Himalayan Thrust results in widespread intracontinental deformation within Central Asia. As the Indian Plate collides with the Eurasian Plate, part of the Eurasian Plate is uplifted and deformed, resulting in the formation of the Tibetan Plateau. The internal deformation is accommodated along strike-slip and to a lesser extent, thrust faults. Major faults, including the Xianshuihe fault system, Kunlun Fault, Altyn Tagh fault, and Longmenshan Fault, accommodate this deformation. The deadly 2008 and 2013 earthquakes occurred due to thrust faulting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China Standard Time
The time in China follows a single standard time offset of UTC+08:00 (eight hours ahead of Coordinated Universal Time), even though the country spans almost five geographical time zones. The official national standard time is called ''Beijing Time'' (BJT, ) domestically and ''China Standard Time'' (CST) internationally. Daylight saving time has not been observed since 1991. China Standard Time (UTC+8) is consistent across Mainland China, Hong Kong, Macau, Taiwan, Philippines, Singapore, Brunei, Mongolia, etc. History In the 1870s, the Shanghai Xujiahui Observatory was constructed by a French Catholic missionary. In 1880s officials in Shanghai French Concession started to provide a time announcement service using the Shanghai Mean Solar Time provided by the aforementioned observatory for ships into and out of Shanghai. By the end of 19th century, the time standard provided by the observatory had been switched to GMT+08:00. The practice has spread to other coastal ports, and in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Himalayan Thrust
The Main Himalayan Thrust (MHT) is a décollement under the Himalaya Range. This thrust fault follows a NW-SE strike, reminiscent of an arc, and gently dip towards the north, beneath the region. It is the largest active continental megathrust fault in the world. Overview The MHT accommodates crustal shortening of India and Eurasia as a result of the ongoing collision between the Indian and Eurasian plates. Deformation of the crust is also accommodated along splay structures including the Main Frontal Thrust (MFT), Main Boundary Thrust (MBT), Main Central Thrust (MCT) and possibly the South Tibetan Detachment. The MHT is the root detachment of these splays. At this present moment, the MFT and MHT accounts for almost the entire rate of convergence (15-21 mm/yr). This fault defines where the India subcontinent is underthrust beneath the Himalayan orogenic wedge. In April 2015, a section of the MHT produced a blind rupture earthquake, killing nearly 9,000 Nepalese. Associa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Gap
A seismic gap is a segment of an active fault known to produce significant earthquakes that has not slipped in an unusually long time, compared with other segments along the same structure. There is a hypothesis or theory that states that over long periods of time, the displacement on any segment must be equal to that experienced by all the other parts of the fault. Any large and longstanding gap is, therefore, considered to be the fault segment most likely to suffer future earthquakes. The applicability of this approach has been criticised by some seismologists although earthquakes sometimes have occurred in previously-identified seismic gaps. Examples Loma Prieta Seismic Gap, California Prior to the 1989 Loma Prieta earthquake( = 6.9), that segment of the San Andreas fault system recorded much less seismic activity than other parts of the fault. The main shock and aftershocks of the 1989 event occurred within the previous seismic gap. Central Kuril gap, Russia Immediately foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Live Science
Live Science is a science news website run by Future via Purch, which it purchased from Imaginova in 2009. Stories and editorial commentary are typically syndicated to major news outlets, such as Yahoo!, MSNBC, AOL, and Fox News.{{fact, date=March 2020 Live Science was originally launched in 2004, but was subsequently shut down and re-launched in 2007. Live Science covers scientific breakthroughs, research ventures and odd facts from around the world in an online newsmagazine format. Purch consumer brands (including Live Science) were acquired by Future in 2018.{{Cite web , url=https://www.futureplc.com/brand/live-science/ , title=Live Science , work=Future plc Future plc is an international multimedia company established in the United Kingdom in 1985. The company has over 220 brands that span magazines, newsletters, websites, and events in fields such as video games, technology, films, music, photogr ... , access-date=18 December 2018 References {{reflist External links ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longmenshan Fault
The Longmenshan Fault () is a thrust fault which runs along the base of the Longmen Mountains in Sichuan province in southwestern China. The strike of the fault plane is approximately NE. Motion on this fault is responsible for the uplift of the mountains relative to the lowlands of the Sichuan Basin to the east. Representing the eastern boundary of the Qinghai-Tibet Plateau, it is a border formation between the Bayan Kola block in the Plateau and the South China block in the Eurasian Plate. The 2008 Wenchuan, 2013 Lushan and 2022 Ya'an earthquakes occurred along this fault. A study by the China Earthquake Administration (CEA) states: "The late-Cenozoic deformations in this fault (''that caused the 2008 Wenchuan earthquake'') are concentrated in the Guanxian-Jiangyou fracture (hill-front fracture), Yingxiu- Beichuan fracture (mid-fracture), Wenchuan-Mao County fracture (hill-back fracture), and their related folds. The recent Ms 8.0 earthquake occurred on the Yingxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altyn Tagh Fault
The Altyn Tagh Fault (ATF) is a 2,000 km long, active, sinistral (left lateral) strike-slip fault that forms the northwestern boundary of the Tibetan Plateau with the Tarim Basin. It is one of the major sinistral strike-slip structures that together help to accommodate the eastward motion of this zone of thickened crust, relative to the Eurasian Plate. A total displacement of about ~475 km has been estimated for this fault zone since the middle Oligocene, although the amount of displacement, age of initiation and slip rate are disputed. Tectonic setting The Tibetan Plateau is an area of thickened continental crust, a result of the ongoing collision of the Indo-Australian Plate with the Eurasian Plate. The way in which this zone accommodates the collision remains unclear with two end-member models being proposed. The first regards the crust as being made up of a mosaic of strong blocks separated by weak fault zones, the 'microplate' model. The second regards the deformatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xianshuihe Fault System
The Xianshuihe fault system is a major active sinistral (left-lateral) strike-slip fault zone in southwestern China, at the eastern edge of the Tibetan Plateau. It has been responsible for many major earthquakes, and is one of the most seismically active fault zones in this part of China. Tectonic setting The Xianshuihe fault system lies within the complex zone of continental collision between the Indian Plate and the Eurasian Plate. It forms one of a set of sinistral fault zones that help accommodate the eastward spreading of the Tibetan Plateau. The fault zone defines the northern and eastern edges of the Sichuan-Yunnan block, and the southeastern boundary of the Bayan Har block. Geometry The Xianshuihe fault system comprises several distinct segments, with an overall length of about 350 km. The main segments are the Ganzi (or Ganzi-Yushu), the Xianshuihe, the Anninghe-Zemuhe, and the Xiaojiang faults. Seismicity Movements on this fault system have been responsible for man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular ''klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is referred to as a ''blind thrust'' fault. Because of the lack of surface evidence, blind thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strike-slip
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 blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibetan Plateau
The Tibetan Plateau (, also known as the Qinghai–Tibet Plateau or the Qing–Zang Plateau () or as the Himalayan Plateau in India, is a vast elevated plateau located at the intersection of Central, South and East Asia covering most of the Tibet Autonomous Region, most of Qinghai, western half of Sichuan, Southern Gansu provinces in Western China, southern Xinjiang, Bhutan, the Indian regions of Ladakh and Lahaul and Spiti (Himachal Pradesh) as well as Gilgit-Baltistan in Pakistan, northwestern Nepal, eastern Tajikistan and southern Kyrgyzstan. It stretches approximately north to south and east to west. It is the world's highest and largest plateau above sea level, with an area of (about five times the size of Metropolitan France). With an average elevation exceeding and being surrounded by imposing mountain ranges that harbor the world's two highest summits, Mount Everest and K2, the Tibetan Plateau is often referred to as "the Roof of the World". The Tibetan Plateau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
