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June 2022 Afghanistan Earthquake
A deep earthquake measuring Moment magnitude scale, magnitude () 6.2 struck southeastern Afghanistan on 22 June 2022 at 01:24:36 Afghanistan Time, AFT (on 21 June 2022 at 20:54:36 UTC). The earthquake had a maximum Modified Mercalli intensity scale, Modified Mercalli intensity of IX (''Violent''). There were 1,052–1,163 deaths and 1,627–2,976 injured in Afghanistan and Pakistan. The worst affected provinces in Afghanistan were Paktika, Paktia, Khost and Nangarhar. Casualties and damage also occurred in Pakistan's Khyber Pakhtunkhwa. At least 10,000 homes collapsed or were severely damaged. The earthquake's shallow hypocenter, proximity to populated areas and low building quality contributed to its destructive effects. Shaking was felt over away by at least 119 million people, including Pakistan's Punjab, Pakistan, Punjab and parts of India and Iran. Earthquake More than 7,000 people in Afghanistan have been killed by earthquakes in the past decade, averaging 560 deaths a ... [...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 geological 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2002 Hindu Kush Earthquakes
The 2002 Hindu Kush earthquakes struck in northern Afghanistan, with the two most destructive events striking during the month of March. At least 169 people were killed with a very large and intermediate-depth 7.4 event on March 3. Three weeks later, at least 1,200 were killed during a moderate but shallow 6.1 event that had a maximum Mercalli intensity of VII (''Very strong''). A 5.9 aftershock on April 12, which had a Mercalli intensity of VII (''Very strong''), killed an additional 50 people. The 7.4 and 6.1 reverse events were focused in the Hindu Kush mountain range area. Tectonic setting Northern Afghanistan lies within the broad zone of continuing collision between the Indian plate and the Eurasian plate. The area is seismically active, particularly as a result of faulting at just over 200 km depth within the descending slab. Many large events of M ≥ 7 have been observed in the Hindu Kush, all with similar epicenters, with an approximate periodicity of abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on March 3, 1879, to study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The agency also makes maps of planets and moons, based on data from U.S. space probes. The sole scientific agency of the U.S. Department of the Interior, USGS is a fact-finding research organization with no regulatory responsibility. It is headquartered in Reston, Virginia, with major offices near Lakewood, Colorado; at the Denver Federal Center; and in NASA Research Park in California. In 2009, it employed about 8,670 people. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on its hundredth anniversary, was "Earth Science in the Pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crust (geology)
In geology, the crust is the outermost solid shell of a planet, dwarf planet, or natural satellite. It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be defined based on its phase (solid crust vs. liquid mantle). The crusts of Earth, Mercury, Venus, Mars, Io, the Moon and other planetary bodies formed via igneous processes and were later modified by erosion, impact cratering, volcanism, and sedimentation. Most terrestrial planets have fairly uniform crusts. Earth, however, has two distinct types: continental crust and oceanic crust. These two types have different chemical compositions and physical properties and were formed by different geological processes. Types of crust Planetary geologists divide crust into three categories based on how and when it formed. Primary crust / primordial crust This is a planet's "original" crust. It forms from solidification of a magma ocean. Toward the end o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismicity
Seismicity is a measure encompassing earthquake occurrences, mechanisms, and magnitude at a given geographical location. As such, it summarizes a region's seismic activity. The term was coined by Beno Gutenberg and Charles Francis Richter in 1941. Seismicity is studied by geophysicists. Calculation of seismicity Seismicity is quantitatively computed. Generally, the region under study is divided in equally sized areas defined by latitude and longitude, and the Earth's interior is divided into various depth intervals on account of Earth's layering: Up to depth, , and > . The usual formula to calculate seismicity is: S = \frac where : _i: is the energy of a single seismic event (i.e., earthquake); : _0: interval of latitude; : _0: interval of longitude : _0: interval of the hypocenter; : _0: interval of the time of the seismic event. : The result is seismicity as energy per cubic unit. See also * Moment magnitude scale * Plate tectonics * Seismology * Wadati–Benioff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transpression
In geology, transpression is a type of Strike-slip fault, strike-slip deformation that deviates from simple shear because of a simultaneous component of shortening perpendicular to the fault plane. This movement ends up resulting in oblique shear. It is generally very unlikely that a deforming body will experience "pure" shortening or "pure" strike-slip. The relative amounts of shortening and strike-slip can be expressed in the convergence angle alpha which ranges from zero (ideal strike-slip) to 90 degrees (ideal convergence). During shortening, unless material is lost, transpression produces vertical thickening in the crust. Transpression that occurs on a regional scale along Tectonic plate, plate boundaries is characterized by oblique convergence. More locally, transpression occurs within restraining bends in strike-slip Fault (geology), fault zones. Transpressional structures Transpressional shear zones are characterized by an association of structures that suggest zone-norma ... [...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 northwest-southeast strike, reminiscent of an arc, and gently dips about 10 degrees 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. The MHT absorbs around 20mm/yr of slip, nearly half of the total convergence rate. This slip can be released from small-scale earthquakes and some plastic deformation, but the MHT still accumulates a deficit of moment of . The MHT also remains locked with the overlying Eurasian plate from its surface expression to the front of the higher Himalayas, nearly 100 kilometres away. This locking mechanism combined with the rapid accumulation of deficit of moment are concerning, as some professionals estimate that earthquakes up to the size of 8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Plate
The Indian plate (or India plate) is or was a minor tectonic plate straddling the equator in the Eastern Hemisphere. Originally a part of the ancient continent of Gondwana, the Indian plate broke away from the other fragments of Gondwana and began moving north, carrying Insular India with it. It was once fused with the adjacent Australian plate to form a single Indo-Australian plate, but recent studies suggest that India and Australia may have been separate plates for at least 3 million years. The Indian plate includes most of modern South Asia (the Indian subcontinent) and a portion of the basin under the Indian Ocean, including parts of South China, western Indonesia, and extending up to but not including Ladakh, Kohistan, and Balochistan in Pakistan. Plate movements Until roughly , the Indian plate formed part of the supercontinent, Gondwana, together with modern Africa, Australia, Antarctica, and South America. Gondwana fragmented as these continents drifted apa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oblique Subduction
Oblique subduction is a form of subduction (i.e. a tectonic process involving the convergence of two Tectonic plate, plates where the denser plate descends into Earth's interior) for which the convergence direction differs from 90° to the plate boundary. Most Convergent boundary, convergent boundaries involve oblique subduction, particularly in the Ring of Fire including the Ryukyu Trench, Ryukyu, Aleutian Trench, Aleutian, Middle America Trench, Central America and Peru–Chile Trench, Chile subduction zones. In general, the obliquity angle is between 15° and 30°. Subduction zones with high obliquity angles include Sunda Trench, Sunda trench (ca. 60°) and Ryukyu arc (ca. 50°). Obliquity in plate convergence causes differences in Strike and dip, dipping angle and subduction velocity along the plate boundary. Tectonic processes including Slab rollback, slab roll-back, trench retreat (i.e. a tectonic response to the process of slab roll-back that moves the Oceanic trench, trench ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other 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 rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In Afghanistan
This is a list of earthquakes in Afghanistan. Fairly moderate earthquakes have been very destructive in the country, particularly in the years List of earthquakes in 1998, 1998, List of earthquakes in 2002, 2002 and List of earthquakes in 2023, 2023. This can be blamed on the population residing in mostly Informal housing, informal and adobe houses, which are extremely vulnerable to earthquake shaking. Tectonic setting Afghanistan is situated near the southern extent of the Eurasian plate. Earthquakes See also *Geology of Afghanistan References Sources * Further reading * * * *Wheeler, Russell L. 2005. Seismotectonic Map of Afghanistan, with Annotated Bibliography [electronic Resource] / by Russell L. Wheeler ... [et Al.] ; Prepared Under the Auspices of the U.S. Agency for International Development, U.S. Department of the Interior, U.S. Geological Survey. Reston, Va: U.S. Dept. of the Interior, U.S. Geological Survey. {{DEFAULTSORT:Earthquakes in Afghanistan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
