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1984 Northern Sumatra Earthquake
The 1984 Northern Sumatra earthquake occurred with a moment magnitude of 7.2 on November 17 at 06:49 UTC. The epicentre was located off the coast of Sumatra, near the island of Nias, where building damage was reported. This earthquake could be strongly felt in parts of Northern Sumatra, including Padang and Medan. The focal mechanism corresponded to reverse faulting. Tectonic setting The island of Sumatra lies on the convergent plate boundary between the Indo-Australian Plate and the Eurasian Plate. The convergence between these plates is highly oblique near Sumatra, with the displacement being accommodated by near pure dip-slip faulting along the subduction zone, known as the Sunda megathrust, and near pure strike-slip faulting along the Great Sumatran fault. The major slip events on the subduction zone interface are typically of megathrust type. Historically, megathrust earthquakes have been recorded in 1797, 1833, 1861, 2004, 2005 and 2007, most of them being associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megathrust
Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthquakes are the planet's most powerful, with moment magnitudes (''Mw'') that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes. The thrust faults responsible for megathrust earthquakes often lie at the bottom of oceanic trenches; in such cases, the earthquakes can abruptly displace the sea floor over a large area. As a result, megathrust earthquakes often generate tsunamis that are considerably more destructive than the earthquakes themselves. Teletsunamis can cross ocean basins to devastate areas far from the original earthquake. Terminology and mechanism The term ''megathrust'' refers to an extremely large thrust fault, typically formed at the plate interface along a subduction zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1861 Sumatra Earthquake
Statistically, this year is considered the end of the whale oil industry and (in replacement) the beginning of the petroleum oil industry. Events January–March * January 1 ** Benito Juárez captures Mexico City. ** The first steam-powered carousel is recorded, in Bolton, England. * January 2 – Frederick William IV of Prussia, Friedrich Wilhelm IV of Prussia dies, and is succeeded by Wilhelm I of Germany, Wilhelm I. * January 3 – American Civil War: Delaware votes not to secede from the United States, Union. * January 9 – American Civil War: Mississippi becomes the second state to secede from the Union. * January 10 – American Civil War: Florida secedes from the Union. * January 11 – American Civil War: Alabama secedes from the Union. * January 12 – American Civil War: Major Robert Anderson (Civil War), Robert Anderson sends dispatches to Washington. * January 19 – American Civil War: Georgia (U.S. state), Georgia secedes from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquakes In Sumatra
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from those that are so weak that they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time period. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume. The word ''tremor'' is also used for non-earthquake seismic rumbling. At the Earth's surface, earthquakes manifest themselves by shaking and displacing or disrupting the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquakes In Indonesia
__NOTOC__ This is an incomplete list of more recent recorded major earthquakes that have occurred within the boundaries of Indonesia. The determinants of the activity are indicated by the geology of the region, and the volcanic activity. Large numbers of earthquakes of smaller magnitude occur very regularly due to the meeting of major tectonic plates in the region. Based on the records of the USGS, Indonesia has had more than 150 earthquakes with magnitude > 7 in the period 1901–2019. Earthquakes 2000–present 1900-1999 1629-1899 See also * Eurasian Plate * Geology of Indonesia * Indo-Australian Plate * Krakatoa * List of faults in Indonesia * List of historical earthquakes * List of natural disasters in Indonesia * List of tsunamis affecting Indonesia * List of volcanoes in Indonesia * Seismicity of the Sumatra coast References Sources * Further reading * External links * Hayes, G.P. ''et al.'' 2013Seismicity of the Earth 1900–2012 Suma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States 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 hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In Indonesia
__NOTOC__ This is an incomplete list of more recent recorded major earthquakes that have occurred within the boundaries of Indonesia. The determinants of the activity are indicated by the geology of the region, and the volcanic activity. Large numbers of earthquakes of smaller magnitude occur very regularly due to the meeting of major tectonic plates in the region. Based on the records of the USGS, Indonesia has had more than 150 earthquakes with magnitude > 7 in the period 1901–2019. Earthquakes 2000–present 1900-1999 1629-1899 See also * Eurasian Plate * Geology of Indonesia * Indo-Australian Plate * Krakatoa * List of faults in Indonesia * List of historical earthquakes * List of natural disasters in Indonesia * List of tsunamis affecting Indonesia * List of volcanoes in Indonesia * Seismicity of the Sumatra coast References Sources * Further reading * External links * Hayes, G.P. ''et al.'' 2013Seismicity of the Earth 1900–2012 S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strike And Dip
Strike and dip is a measurement convention used to describe the orientation, or attitude, of a planar geologic feature. A feature's strike is the azimuth of an imagined horizontal line across the plane, and its dip is the angle of inclination measured downward from horizontal. They are used together to measure and document a structure's characteristics for study or for use on a geologic map. A feature's orientation can also be represented by dip and dip direction, using the azimuth of the dip rather than the strike value. Linear features are similarly measured with trend and plunge, where "trend" is analogous to dip direction and "plunge" is the dip angle. Strike and dip are measured using a compass and a clinometer. A compass is used to measure the feature's strike by holding the compass horizontally against the feature. A clinometer measures the features dip by recording the inclination perpendicular to the strike. These can be done separately, or together using a tool such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypocenter
In seismology, a hypocenter or hypocentre () is the point of origin of an earthquake or a subsurface nuclear explosion. A synonym is the focus of an earthquake. Earthquakes An earthquake's hypocenter is the position where the strain energy stored in the rock is first released, marking the point where the fault begins to rupture.''The hypocenter is the point within the earth where an earthquake rupture starts. The epicenter is the point directly above it at the surface of the Earth. Also commonly termed the focus.'' This occurs directly beneath the epicenter, at a distance known as the ''hypocentral depth'' or ''focal depth''. The focal depth can be calculated from measurements based on seismic wave phenomena. As with all wave phenomena in physics, there is uncertainty in such measurements that grows with the wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current Science
''Current Science'' is an English-language peer-reviewed multidisciplinary scientific journal. It was established in 1932 and is published by the Current Science Association along with the Indian Academy of Sciences. According to the ''Journal Citation Reports ''Journal Citation Reports'' (''JCR'') is an annual publicationby Clarivate Analytics (previously the intellectual property of Thomson Reuters). It has been integrated with the Web of Science and is accessed from the Web of Science-Core Collec ...'', the journal has a 2018 impact factor of 0.756. ''Current Science'' is indexed by Web of Science, Current Contents, Geobase, Chemical Abstracts, IndMed and Scopus. The editor-in-chief is S. K. Satheesh of the Indian Institute of Science, Bengaluru. Retrieved 4 February 2018 |
2002 Sumatra Earthquake
The 2002 Sumatra earthquake occurred at 01:26 UTC on 2 November. It had a magnitude of 7.4 on the moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 pa ... with an epicenter just north of Simeulue Regency, Simeulue island and caused three deaths. This earthquake is regarded as a foreshock of the 2004 Indian Ocean earthquake and tsunami, 2004 Indian Ocean earthquake, which had an epicenter about 60 km to the northwest. Tectonic setting The island of Sumatra lies on the Convergent boundary, convergent plate boundary between the Indo-Australian Plate and the Eurasian Plate. The convergence between these plates is highly oblique near Sumatra, with the displacement being accommodated by near pure Fault (geology)#Fault types, dip-slip faulting along the subduction z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2000 Sumatra Earthquake
The 2000 Enggano earthquake struck at 23:28 local time on June 4 with a moment magnitude of 7.9 and a maximum Mercalli intensity of VI (''Strong''). The event occurred off the coast of southern Sumatra, Indonesia near Enggano Island. There were more than 100 fatalities and up to 2,585 injuries. Over 730 aftershocks shook the area afterwards, one just eleven minutes after the mainshock. This was the first and southernmost in a series of very large to great Sumatran earthquakes in the 2000s to rupture almost the entire western part of the Sunda megathrust, most notably including the 9.1–9.3 2004 Indian Ocean earthquake, but also the 8.7 2005 Nias–Simeulue earthquake, and the 7.9–8.4 September 2007 Sumatra earthquakes. Background and tectonics Indonesia is well known for strong earthquakes: the 2000 Enggano event marked the beginning of an ongoing period of seismic activity in the area, highlighted by the 2004 Indian Ocean earthquake. The 2000 Enggano earthquake took pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1935 Sumatra Earthquake
The 1935 Sumatra earthquake occurred at on 28 December. It had a magnitude of 7.7 and a maximum felt intensity of VIII (''Severe'') on the Mercalli intensity scale. It triggered a minor tsunami. Tectonic setting The island of Sumatra lies on the convergent plate boundary between the Indo-Australian Plate and the Eurasian Plate. The convergence between these plates is highly oblique near Sumatra, with the displacement being accommodated by near pure dip-slip faulting along the subduction zone, known as the Sunda megathrust, and near pure strike-slip faulting along the Great Sumatran fault. The major slip events on the subduction zone interface are typically of megathrust type. Historically, great or giant megathrust earthquakes have been recorded in 1797, 1833, 1861, 2004, 2005 and 2007, most of them being associated with devastating tsunamis. Smaller (but still large) megathrust events have also occurred in the small gaps between the areas that slip during the larger event ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
