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2017 Central Mexico Earthquake
The 2017 Puebla earthquake, also known as 19S, struck at 13:14 Central Time Zone, CDT (18:14 Coordinated Universal Time, UTC) on 19 September 2017 with an estimated magnitude of 7.1 and strong shaking for about 20 seconds. Its epicenter was about south of the city of Puebla City, Puebla, Mexico. The earthquake caused damage in the Mexican states of Puebla and Morelos and in the Greater Mexico City area, including the collapse of more than 40 buildings. 370 people were killed by the earthquake and related building collapses, including 228 in Mexico City, and more than 6,000 were injured. The quake coincidentally occurred on the 32nd anniversary of the 1985 Mexico City earthquake, which killed around 10,000 people. The 1985 quake was commemorated, and a national earthquake drill was held, at 11 a.m. local time, just two hours before the 2017 earthquake. Twelve days earlier, the even larger 2017 Chiapas earthquake struck away, off the coast of the state of Chiapas. Bac ... [...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] |
Mexico Tectonic Plates
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundaries with the Pacific Ocean to the west, the Caribbean Sea to the southeast, and the Gulf of Mexico to the east. Mexico covers 1,972,550 km2 (761,610 sq mi), and is the thirteenth-largest country in the world by land area. With a population exceeding 130 million, Mexico is the tenth-most populous country in the world and is home to the largest number of native Spanish speakers. Mexico City is the capital and largest city, which ranks among the most populous metropolitan areas in the world. Human presence in Mexico dates back to at least 8,000 BC. Mesoamerica, considered a cradle of civilization, was home to numerous advanced societies, including the Olmecs, Maya, Zapotecs, Teotihuacan civilization, and Purépecha. Spanish colo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicenter
The epicenter (), epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates. Determination The primary purpose of a seismometer is to locate the initiating points of earthquake epicenters. The secondary purpose, of determining the 'size' or magnitude must be calculated after the precise location is known. The earliest seismographs were designed to give a sense of the direction of the first motions from an earthquake. The Chinese frog seismograph would have dropped its ball in the general compass direction of the earthquake, assuming a strong positive pulse. We now know that first motions can be in almost any direction depending on the type of initiating rupture ( focal mechanism). The first refinement that allowed a more precise determination of the location was the use of a time scale. Instead of merely noting, or recording, the absolute motions of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Seismological Service
The National Seismological Service (, SSN) is a seismological organization in Mexico that studies and records earthquake activity within the country. It is part of the Geophysics Institute at the National Autonomous University of Mexico (UNAM) and is based in Mexico City Mexico City is the capital city, capital and List of cities in Mexico, largest city of Mexico, as well as the List of North American cities by population, most populous city in North America. It is one of the most important cultural and finan .... The SSN was founded on September 5, 1910, by the federal government as part of an international effort to monitor seismic activity. It was transferred to UNAM in 1929 and became part of the UNAM Geophysics Institute in 1948. The SSN established its first nine earthquake monitoring stations were installed between 1910 and 1923, including seven that have operated continuously since as the oldest system in North America. Currently, the SSN has 22 seismic observatories ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2017 Central Mexico Earthquake In México City
Seventeen or 17 may refer to: *17 (number) * One of the years 17 BC, AD 17, 1917, 2017, 2117 Science * Chlorine, a halogen in the periodic table * 17 Thetis, an asteroid in the asteroid belt Literature Magazines * ''Seventeen'' (American magazine), an American magazine * ''Seventeen'' (Japanese magazine), a Japanese magazine Novels * ''Seventeen'' (Tarkington novel), a 1916 novel by Booth Tarkington *''Seventeen'' (''Sebuntiin''), a 1961 novel by Kenzaburō Ōe *'' Seventeen'' (''Kuraimāzu hai''), a 2003 novel by Hideo Yokoyama * ''Seventeen'' (Serafin novel), a 2004 novel by Shan Serafin Stage and screen Film * ''Seventeen'' (1916 film), an American silent comedy film *''Number Seventeen'', a 1932 film directed by Alfred Hitchcock * ''Seventeen'' (1940 film), an American comedy film *''Stalag 17'', an American war film *''Eric Soya's '17''' (Danish: ''Sytten''), a 1965 Danish comedy film * ''Seventeen'' (1985 film), a documentary film * ''17 Again'', a 2009 film whose wor ... [...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] |
Remotely Triggered Earthquakes
Remotely triggered earthquakes are a result of the effects of large earthquakes at considerable distance, outside of the immediate aftershock zone. The farther one gets from the initiating earthquake in both space and time, the more difficult it is to establish an association. The physics of triggering an earthquake are complex. Most earthquake-generating zones are in a state of being close to failure. If such a zone were to be left completely alone, it would generate significant earthquakes spontaneously. Remote earthquakes, however, are in a position to disturb this critical state, either by shifting the stresses statically, or by dynamic change caused by passing seismic waves. The first type of triggering may be due to static changes in the critical state. For example, after the magnitude 7.3 Landers earthquake struck California in 1992, it is said that "the earthquake map of California lit up like a Christmas tree". This event reinforced the idea of remotely triggered earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aftershock
In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in Epicenter, the same area of the Mainshock, main shock, caused as the displaced Crust (geology), crust adjusts to the effects of the main shock. Large earthquakes can have hundreds to thousands of instrumentally detectable aftershocks, which steadily decrease in magnitude and frequency according to #Aftershock size and frequency with time, a consistent pattern. In some earthquakes the main rupture happens in two or more steps, resulting in multiple main shocks. These are known as doublet earthquakes, and in general can be distinguished from aftershocks in having similar magnitudes and nearly identical seismic waveforms. Distribution of aftershocks Most aftershocks are located over the full area of fault rupture and either occur along the fault plane itself or along other faults within the volume affected by the strain associated with the main shock. Typically, aftershocks are found up to a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Texcoco
Lake Texcoco (; ) was a natural saline lake within the ''Anahuac'' or Valley of Mexico. Lake Texcoco is best known for an island situated on the western side of the lake where the Mexica built the city of Mēxihco Tenōchtitlan, which would later become the capital of the Aztec Empire. After the Spanish conquest, efforts to control flooding led to most of the lake being drained. The entire lake basin is now almost completely occupied by Mexico City, the capital of the present-day nation of Mexico. Drainage of the lake has led to serious ecological and human consequences. The local climate and water availability have changed considerably, contributing to water scarcity in the area; subsequent groundwater extraction leads to land subsidence under much of the city. Native species endemic to the lake region, such as the axolotl, have become severely endangered or extinct due to ecosystem change. Geography The Valley of Mexico is a basin with an average elevation of above mean s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rivera Plate
The Rivera plate is a small tectonic plate (a microplate) located off the west coast of Mexico, just south of the Baja California peninsula. It is bounded on the northwest by the East Pacific Rise, on the southwest by the Rivera Transform Fault, on the southeast by a deformation zone, and on the northeast by the Middle America Trench and another deformation zone. The Rivera plate is believed to have separated from the Cocos plate located to its southeast about 5–10 million years ago. Seismicity and tomography images show that the Rivera plate dips at 40° beneath the forearc region and then dips ~70° beneath the Trans-Mexican Volcanic Belt. The subduction of the Rivera plate under the North American plate, in the Mid-American Trench, has been the cause of the strongest earthquakes in the history of Mexico, including the largest earthquake in Mexico during the 20th century which occurred on June 3, 1932 in the state of Jalisco. The quake had a magnitude of 8.2 with a mag ... [...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] |
