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2001 Gujarat Earthquake
The 2001 Gujarat earthquake, also known as the Bhuj earthquake, occurred on 26 January, India's 52nd Republic Day, at . The epicentre was about 9 km south-southwest of the village of Chobari in Bhachau Taluka of Kutch District of Gujarat, India. The intraplate earthquake measured 7.7 on the moment magnitude scale and had a maximum felt intensity of X (''Extreme'') on the Mercalli intensity scale. The earthquake killed between 13,805 and 20,023 people (including 18 in southeastern Pakistan), injured another 167,000 and destroyed nearly 340,000 buildings. Tectonic setting Gujarat lies 300–400 km from the plate boundary between the Indian Plate and the Eurasian Plate, but the current tectonics are still governed by the effects of the continuing continental collision along this boundary. During the break-up of Gondwana in the Jurassic, this area was affected by rifting with a roughly west–east trend. During the collision with Eurasia the area has undergone shorteni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
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 geologic 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] |
Continental Collision
In geology, continental collision is a phenomenon of plate tectonics that occurs at convergent boundaries. Continental collision is a variation on the fundamental process of subduction, whereby the subduction zone is destroyed, mountains produced, and two continents sutured together. Continental collision is only known to occur on Earth. Continental collision is not an instantaneous event, but may take several tens of millions of years before the faulting and folding caused by collisions stops. The collision between India and Asia has been going on for about 50 million years already and shows no signs of abating. Collision between East and West Gondwana to form the East African Orogen took about 100 million years from beginning (610 Ma) to end (510 Ma). The collision between Gondwana and Laurasia to form Pangea occurred in a relatively brief interval, about 50 million years long. Subduction zone: the collision site The process begins as two cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anjar, India
Anjar is a town, township and municipality of the Kachchh district in the state of Gujarat, India. Founded in 650 AD, Anjar is a culturally diverse town of historic importance in the region. It is home to several historic religious temples, including the Jesal-Toral Shrines built in honour of a fourteenth century couple, whose lives inspired works of art and cinema. The town was devastated by several earthquakes, including the 1819 Rann of Kutch earthquake and 2001 Gujarat earthquake. In recent years, Anjar has become a hub of manufacturing activity. History The foundation and early history of the town is unclear, due to a lack of written evidence and documentation. Popular folklore suggests a group of settlers led by Ajay Pal Chauhan (also called Ajepal) – the brother of the king of neighbouring Ajmer – arrived in Anjar in 650 AD ( Samvat 707). Soon after, Ajay Pal devoted his life to asceticism after his Chauhan clan was defeated by Muslim Rajputs. At different points in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bhuj
Bhuj () is a Municipality and District Headquarters of Kutch District in the state of Gujarat, India. Etymology According to legend, Kutch was ruled by the Nāga chieftains in the past. Sagai, a queen of Sheshapattana, who was married to King Bheria Kumar, rose up against Bhujanga, the last chieftain of Naga. After the battle, Bheria was defeated and Queen Sagai committed sati. The hill where they lived later came to be known as Bhujia Hill and the town at the foothill as Bhuj. Bhujang was later worshiped by the people as snake god, '' Bhujanga'', and a temple was constructed to revere him. History Bhuj was founded by Rao Hamir in 1510 and was made the capital of Kutch by Rao Khengarji I in 1549. Its foundation stone as state capital was formally laid on Vikram Samvat 1604 Maagha 5th (approx. 25 January 1548). From 1590 onwards, when Rao was forced to acknowledge the Mughal supremacy, Bhuj came to be known as Suleiman Nagar amongst Muslims. The city's walls were built b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismological Society Of America
The Seismological Society of America (SSA) is an international scientific society devoted to the advancement of seismology and the understanding of earthquakes for the benefit of society. Founded in 1906, the society has members throughout the world representing seismologists and other geophysicists, geologists, engineers, insurers, and policy-makers in preparedness and safety. History The society was established by academic, government, and other scientific and engineering professionals in the months following the April 18th San Francisco earthquake, with the first meeting of the Board of Directors taking place on December 1, 1906. Publications The Seismological Society of America publishes the '' Bulletin of the Seismological Society of America'' (''BSSA''), a journal of research in earthquake seismology and related disciplines since 1911, and ''Seismological Research Letters'' (''SRL''), which serves as a forum for informal communication among seismologists, as well as b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1819 Rann Of Kutch Earthquake
The 1819 Rann of Kutch earthquake occurred at about 18:45 to 18:50 local time on 16 June. It had an estimated magnitude ranging from 7.7 to 8.2 on the moment magnitude scale and a maximum perceived intensity of XI (''Extreme'') on the Mercalli intensity scale. It triggered a tsunami and caused at least 1,543 deaths. The earthquake caused an area of subsidence that formed the Sindri Lake and a local zone of uplift to the north about 80 km long, 6 km wide and 6 m high that dammed the Koree / Kori / Puran / Nara river. This natural dam was known as the Allah Bund ("Dam of God"). Tectonic setting The Kutch District of modern-day Gujarat lies 300–400 km from the plate boundary between the Indian Plate and the Eurasian Plate, but the current tectonics is still governed by the effects of the continuing continental collision along this boundary. During the break-up of Gondwana in the Jurassic period, this area was affected by rifting with a roughly west–east ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inversion (geology)
In structural geology inversion or basin inversion relates to the relative uplift of a sedimentary basin or similar structure as a result of crustal shortening. This normally excludes uplift developed in the footwalls of later extensional faults, or uplift caused by mantle plumes. "Inversion" can also refer to individual faults, where an extensional fault is reactivated in the opposite direction to its original movement. The term ''negative inversion'' is also occasionally used to describe the reactivation of reverse faults and thrusts during extension. The term "inversion" simply refers to the fact that a relatively low-lying area is uplifted – the rock sequence itself is not normally inverted. Formation Many inversion structures are caused by the direct reactivation of pre-existing extensional faults. In some cases only the deeper parts of the fault are reactivated and the shortening is accommodated over a much broader area in the shallow part of the section. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Mechanism
The focal mechanism of an earthquake describes the deformation in the source region that generates the seismic waves. In the case of a fault-related event it refers to the orientation of the fault plane that slipped and the slip 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", that is, 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 typically displayed graphically using a so-called ''beachball'' diagram. The pattern o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (''fault bend fold''), at the tip of a propagating fault (''fault propagation fold''), by differential compaction or due to ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
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 geologic 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] |
