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1965 Valparaíso Earthquake And The El Cobre Dam Failures
The 1965 Valparaíso earthquake (also known as the La Ligua earthquake) struck near La Ligua in Valparaíso Region, Chile, about from the capital Santiago on Sunday, March 28 at 12:33 local time. The moment magnitude () 7.4–7.6 earthquake killed 400–500 people and inflicted US$1 billion (adjusted for inflation) in damages. Many deaths were from El Cobre, a mining location that was wiped out after a series of dam failures caused by the earthquake spilled mineral waste onto the area, burying hundreds of residents. The shock was felt throughout the country and along the Atlantic coast of Argentina. Tectonic setting Earthquakes are frequent in Chile, which lies in the so-called Ring of Fire, where many of the world's active volcanoes and seismic activities are concentrated at. Off the coast of Chile, the Nazca Plate subducts beneath the South American Plate along the Peru–Chile Megathrust; a convergent plate boundary. Active subduction produce large earthquakes includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time In Chile
Time in Chile is divided into three time zones. Most of Continental Chile uses the time offset UTC−04:00 in winter time and UTC−03:00 in summer time, while the Magallanes and Chilean Antarctica region uses the time offset UTC-03:00 the whole year. Additionally, Easter Island uses the time offset UTC−06:00 in winter time and UTC−05:00 in summer time. Until 2015, Continental Chile used the time offset UTC−04:00 and Easter Island used UTC−06:00 for standard time, with daylight saving time roughly between October and March every year. In January 2015, the Chilean government announced that the entire country would keep the time offset used during daylight saving time permanently. However, the annual time change was reinstated in 2016 after feedback from the public about an increase in truancy during the winter months, complaints about older computers and other electronic devices not using the right time zone, and fruit growers reporting a 15% loss in productivity. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Plate Boundary
A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a plane where many earthquakes occur, called the Wadati–Benioff zone. These collisions happen on scales of millions to tens of millions of years and can lead to volcanism, earthquakes, orogenesis, destruction of lithosphere, and deformation. Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere. The geologic features related to convergent boundaries vary depending on crust types. Plate tectonics is driven by convection cells in the mantle. Convection cells are the result of heat generated by the radioactive decay of elements in the mantle escaping to the surface and the return of cool materials from the surface to the mantle. These convection cells bring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physics Of The Earth And Planetary Interiors
''Physics of the Earth and Planetary Interiors'', established in October 1967, is a biweekly peer-reviewed scientific journal published by Elsevier. The co-editors are A. Ferreira (University College London), K. Hirose (Tokyo Institute of Technology), D. Jault (Grenoble Alpes University), and C. Michaut ( Ecole normale superieure de Lyon). The journal covers the physical and chemical processes of planetary interiors. Topical coverage broadly encompasses planetary physics, geodesy, and geophysics. Publishing formats include original research papers, review articles, short communications and book reviews on a regular basis. Occasional special issues are set aside for proceedings of conferences. The journal has a 2020 impact factor of 2.261. Abstracting and indexing This journal is indexed in the following bibliographic databases: * Science Citation Index * Current Contents/Physical, Chemical & Earth Sciences * Chemical Abstracts Service – CASSI * AGI's Bibliography and I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geophysical Journal International
''Geophysical Journal International'' is a monthly peer-reviewed scientific journal published by Oxford University Press on behalf of the Royal Astronomical Society and the Deutsche Geophysikalische Gesellschaft (German Geophysical Society). The journal publishes original research papers, research notes, letters, and book reviews. It was established in 1922. The editor-in-chief is Joerg Renner (Ruhr University Bochum). The journal covers research on all aspects of theoretical, computational, applied and observational geophysics. History The journal was formerly entitled ''Geophysical Journal'' (Oxford) from January 1988 to June 1989. The ''Geophysical Journal'' was itself formed by the merger of three other publications: ''Geophysical Journal of the Royal Astronomical Society'', ''Journal of Geophysics'', and ''Annales Geophysicae, Series B: Terrestrial and Planetary Physics''. ''Geophysical Journal of the Royal Astronomical Society'' was in existence from March 1958 to December ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interplate Earthquake
An interplate earthquake is an earthquake that occurs at the boundary between two tectonic plates. Earthquakes of this type account for more than 90 percent of the total seismic energy released around the world. If one plate is trying to move past the other, they will be locked until sufficient stress builds up to cause the plates to slip relative to each other. The slipping process creates an earthquake with relative displacement on either side of the fault, resulting in seismic waves which travel through the Earth and along the Earth's surface. Relative plate motion can be lateral as along a transform fault boundary, vertical if along a convergent boundary (i.e. subduction or thrust/reverse faulting) or a divergent boundary (i.e. rift zone or normal faulting), and oblique, with horizontal and lateral components at the boundary. Interplate earthquakes associated at a subduction boundary are called megathrust earthquakes, which include most of the Earth's largest earthquakes. Intra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foreshock
A foreshock is an earthquake that occurs before a larger seismic event (the mainshock) and is related to it in both time and space. The designation of an earthquake as ''foreshock'', ''mainshock'' or aftershock is only possible after the full sequence of events has happened. Occurrence Foreshock activity has been detected for about 40% of all moderate to large earthquakes, and about 70% for events of M>7.0. They occur from a matter of minutes to days or even longer before the main shock; for example, the 2002 Sumatra earthquake is regarded as a foreshock of the 2004 Indian Ocean earthquake with a delay of more than two years between the two events. Some great earthquakes (M>8.0) show no foreshock activity at all, such as the M8.6 1950 India–China earthquake. The increase in foreshock activity is difficult to quantify for individual earthquakes but becomes apparent when combining the results of many different events. From such combined observations, the increase before the mai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredth annivers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mainshock
In seismology, the mainshock is the largest earthquake in a sequence, sometimes preceded by one or more foreshocks, and almost always followed by many aftershocks. Foreshock A foreshock is an earthquake that occurs before a larger seismic event (the mainshock) and is related to it in both time and space. The designation of an earthquake as ''foreshock'', ''mainshock'' or aftershock is only possible after the full sequence of events has happened. Aftershock In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in the same area of the main shock, caused as the displaced 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 known laws. 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 b ... [...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. Surface damage Before the instrumental period of earthquake observation, the epicenter was thought to be the location where the greatest damage occurred, but the subsurface fault rupture may be long and spread surface damage across the entire rupture zone. As an example, in the magnitude 7.9 Denali earthquake of 2002 in Alaska, the epicenter was at the western end of the rupture, but the greatest damage was about away at the eastern end. Focal depths of earthquakes occurring in continental crust mostly range from . Continental earthquakes below are rare whereas in subduction zone earthquakes can originate at depths deeper than . Epicentral distance During an earthquake, seismic waves propagate in all directions from the hypocenter. Seismic shadowing occurs on the opposite s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Los Vilos, Chile
Los Vilos (From mapuche: ''Filu'', ‘snake’) ? is both a Chilean coastal commune and a coastal city with over 9,000 inhabitants (18,275 in comuna), located in the Province of Choapa, part of the IV Region of Coquimbo. The city has a harbour called Puerto Punta Chungo, that ships the material of Los Pelambres mine. Fishing is one of its main activities. The city also has a significant amount of tourism, mainly due to its two beaches: La Principal and Las Conchas. It is located at from La Serena and from Santiago. The city was founded in 1830, and was declared a minor harbor in 1855. History Los Vilos has existed as a small informal settlement since 1835, when the government realised that a port was needed in that region to expand the reach of commerce in the country. On January 3, 1855, it was declared a minor port by then president, Manuel Montt and by his Minister of Finance, José María Berganza, through a supreme decree of the Finance Ministry. On April of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsunamis
A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonations, landslides, glacier calvings, meteorite impacts and other disturbances) above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event. Tsunami waves do not resemble normal undersea currents or sea waves because their wavelength is far longer. Rather than appearing as a breaking wave, a tsunami may instead initially resemble a rapidly rising tide. For this reason, it is often referred to as a tidal wave, although this usage is not favoured by the scientific community because it might give ... [...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] |
