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1988 Lancang–Gengma Earthquakes
On 6 November 1988, two earthquakes struck Lancang Lahu Autonomous County, Lancang and Gengma Dai and Va Autonomous County, Gengma counties, Yunnan, near the China–Myanmar border. These earthquakes measured moment magnitude () 7.0 and 6.9, respectively, spaced 12 minutes apart. These earthquakes were assigned a maximum China seismic intensity scale, China seismic intensity of IX and X, respectively. Between 748 and 939 people were killed; more than 7,700 were injured. Both earthquakes caused damage and economic losses estimated at Renminbi, CN¥ 2.05 billion (CN¥ billion in ). Moderately large aftershocks continued to rock the region, causing additional casualties and damage. Tectonic setting The Shan Hills, Shan Plateau is crisscrossed by strike-slip faults to accommodate crustal rotation of the Sunda plate, Sunda Block and crustal deformation, deformation as a result of the Geology of the Himalayas, India–Asia collision, where the Indian plate is underthrusted b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China–Myanmar Border
The China–Myanmar border is the international border between the territory of the People's Republic of China and Myanmar (formerly ''Burma''). The border is 2,129 km (1,323 mi) in length and runs from the tripoint with India in the north to the tripoint with Laos in the south. Description The border begins in the north at the tripoint with India just north of the Diphu Pass and then runs briefly north-east, across the Nanmi Pass and Hkakabo Razi (5,881 m), the highest mountain in Southeast Asia. It then turns to the south-east, running broadly south and then south-west across the Hengduan Mountains, Hengduan and Gaoligong Mountains via a series of irregular lines. In the vicinity of Ruili the border briefly utilises parts of the Taping River, Taping and Nanwan rivers, before turning south-east to join the Shweli River, which it utilises for a period towards the north-east. The border then continues through mountainous terrain in a broadly (though often convoluted) south ... [...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 called a ''blind thrust'' fault. Because of the lack of surface evidence, blind thrust fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coulomb Stress Transfer
Coulomb stress transfer is a Seismology, seismic-related geology, geological process of Stress (mechanics), stress changes to surrounding material caused by local discrete deformation events. Using mapped displacements of the Earth's surface during earthquakes, the computed Coulomb stress changes suggest that the stress relieved during an earthquake not only dissipates but can also move up and down Fault (geology), fault segments, concentrating and promoting subsequent tremors. Importantly, Coulomb stress changes have been applied to earthquake-forecasting models that have been used to assess potential Seismic hazard, hazards related to earthquake activity. Coulomb stress change The Mohr–Coulomb theory, Coulomb failure criterion requires that the Coulomb stress exceeds a value σf defined by the shear stress τB, normal stress σB, pore pressure p, and coefficient of friction μ of a failure plane, such that It is also often assumed that changes in pore fluid pressure induced b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Oceanic And Atmospheric Administration
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with Weather forecasting, forecasting weather, monitoring oceanic and atmospheric conditions, Hydrography, charting the seas, conducting deep-sea exploration, and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone. The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland. History NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: * United States Coast and Geodetic Survey, formed in 1807 * National Weather Service, Weather Bureau of the United States, formed in 1870 * United States Fish Commission, Bureau of Commercial Fisheries, formed in 1871 (research fleet only) * NOAA Commissioned Corps, Coast and Geodetic Survey Corps, formed in 1917 The most direct predecessor of NOAA was the Enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Geophysical Data Center
The United States National Geophysical Data Center (NGDC) provided scientific stewardship, products and services for geophysical data describing the solid earth, marine, and solar-terrestrial environment, as well as earth observations from space. It was established in 1965 as part of the new Environmental Science Services Administration until that organization became the National Oceanic & Atmospheric Administration (NOAA) in 1970. In 2015, NGDC was merged with the National Climatic Data Center (NCDC) and the National Oceanographic Data Center (NODC) into the National Centers for Environmental Information (NCEI). Location and controlling bodies Since 1972 the NGDC was located in Boulder, Colorado as a part of the US Department of Commerce (USDOC), National Oceanic & Atmospheric Administration (NOAA), National Environmental Satellite, Data and Information Service (NESDIS). Data holdings NGDC's data holdings contained more than 300 digital and analog databases, with over 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1995 Myanmar–China Earthquake
The 1995 Menglian earthquake or Myanmar–China earthquake occurred on 12 July at 05:46 local time in the Myanmar–China border region. The earthquake had an epicenter on the Myanmar side of the border, located in the mountainous region of Shan State. It registered 7.3 on the Chinese surface-wave magnitude scale () and 6.8 on the moment magnitude scale (). With a maximum Mercalli intensity assigned at VIII, it killed 11 people and left another 136 injured. Over 100,000 homes in both countries were destroyed and 42,000 seriously damaged."> Some damage to structures were also reported in Chiang Mai and Chiang Rai, Thailand. The low death toll from this earthquake was attributed to an early warning issued prior to it happening. Precursor events including foreshocks and some seismic anomalies led to an evacuation of the area before the mainshock struck. It is thought to be one of the few successfully predicted earthquakes in history. Tectonic setting The Shan Plateau which encompa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salween
The Salween is a Southeast Asian river, about long, flowing from the Tibetan Plateau south into the Andaman Sea. The Salween flows primarily within southwest China and eastern Myanmar, with a short section forming the border of Myanmar and Thailand. Throughout most of its course, it runs swiftly through rugged mountain canyons. Despite the river's great length, only the last are navigable, where it forms a modest estuary and delta at Mawlamyine. The river is known by various names along its course, including the Thanlwin (named after ''Elaeocarpus'' sp., an olive-like plant that grows on its banks) in Myanmar and the Nu Jiang (or Nu River, named after Nu people) in China. The commonly used spelling "Salween" is an anglicisation of the Burmese name dating from 19th-century British maps. Due to its great range of elevation and latitude coupled with geographic isolation, the Salween basin is considered one of the most ecologically diverse regions in the world, containing an estim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mekong
The Mekong or Mekong River ( , ) is a transboundary river in East Asia and Southeast Asia. It is the world's twelfth-longest river and the third-longest in Asia with an estimated length of and a drainage area of , discharging of water annually. From its headwaters in the Tibetan Plateau, the river runs through Southwest China (where it is officially called the Lancang River), Myanmar, Laos, Thailand, Cambodia, and southern Vietnam. The extreme seasonal variations in flow and the presence of rapids and waterfalls in the Mekong make navigation difficult, though the river remains a major trade route between Tibet and Southeast Asia. The construction of hydroelectric dams along the Mekong in the 2000s through the 2020s has caused serious problems for the river's ecosystem, including the exacerbation of drought. Names The Mekong was originally called ''Mae Nam Khong'' from a contracted form of Kra-Dai shortened to ''Mae Khong''. In Thai and Lao, ''Mae Nam'' ("Mother ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Zone
In geology, a shear zone is a thin zone within the Earth's crust or upper mantle that has been strongly deformed, due to the walls of rock on either side of the zone slipping past each other. In the upper crust, where rock is brittle, the shear zone takes the form of a fracture called a Fault (geology), fault. In the lower crust and mantle, the extreme conditions of pressure and temperature make the rock ductile. That is, the rock is capable of slowly deforming without fracture, like hot metal being worked by a blacksmith. Here the shear zone is a wider zone, in which the ductile rock has slowly flowed to accommodate the relative motion of the rock walls on either side. Because shear zones are found across a wide depth-range, a great variety of different rock types with their characteristic structures are associated with shear zones. General introduction A shear zone is a zone of strong deformation (with a high strain rate) surrounded by rocks with a lower state of Deforma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Mechanism
The focal mechanism of an earthquake describes the Fault (geology)#Slip.2C heave.2C throw, deformation in the Hypocenter, source region that generates the seismic waves. In the case of a Fault (geology), fault-related event, it refers to the orientation of the fault plane that slipped, and the slip Euclidean vector, vector and is also known as a fault-plane solution. Focal mechanisms are derived from a solution of the moment tensor for the earthquake, which itself is estimated by an analysis of observed seismic waveforms. The focal mechanism can be derived from observing the pattern of "first motions", whether the first arriving P waves break up or down. This method was used before waveforms were recorded and analysed digitally, and this method is still used for earthquakes too small for easy moment tensor solution. Focal mechanisms are now mainly derived using semi-automatic analysis of the recorded waveforms. Moment tensor solutions The moment tensor solution is displayed gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southeast Asia
Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Australia, Australian mainland, which is part of Oceania. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, and to the south by Australia (continent), Australia and the Indian Ocean. Apart from the British Indian Ocean Territory and two out of Atolls of the Maldives, 26 atolls of the Maldives in South Asia, Maritime Southeast Asia is the only other subregion of Asia that lies partly within the Southern Hemisphere. Mainland Southeast Asia is entirely in the Northern Hemisphere. Timor-Leste and the southern portion of Indonesia are the parts of Southeast Asia that lie south of the equator. The region lies near the intersection of Plate tectonics, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
