A dome is an architectural element that resembles the hollow upper half of a sphere. The precise definition has been a matter of controversy. There are a wide variety of forms and specialized terms to describe them. A dome can rest upon a rotunda or drum, can be supported by columns or piers that transition to the dome through squinches or pendentives. A lantern may itself have another dome. Domes have a long architectural lineage that extends back into prehistory and they have been constructed from mud, stone, brick, metal and plastic over the centuries; the symbolism associated with domes includes mortuary and governmental traditions that have developed over time. Domes have been found from early Mesopotamia, they are found in Persian, Hellenistic and Chinese architecture in the Ancient world, as well as among a number of contemporary indigenous building traditions. Dome structures were popular in Byzantine and medieval Islamic architecture, there are numerous examples from Western Europe in the Middle Ages.
The Renaissance architectural style spread from Italy in the Early modern period. Advancements in mathematics and production techniques since that time resulted in new dome types; the domes of the modern world can be found over religious buildings, legislative chambers, sports stadiums, a variety of functional structures. The English word "dome" derives from the Latin domus from ancient Greek δόμος, which, up through the Renaissance, labeled a revered house, such as a Domus Dei, or "House of God", regardless of the shape of its roof; this is reflected in the uses of the Italian word duomo, the German/Icelandic/Danish word dom, the English word dome as late as 1656, when it meant a "Town-House, Guild-Hall, State-House, Meeting-House in a city." The French word dosme came to acquire the meaning of a cupola vault by 1660. This French definition became the standard usage of the English dome in the eighteenth century as many of the most impressive Houses of God were built with monumental domes, in response to the scientific need for more technical terms.
A dome is a rounded vault made of either curved segments or a shell of revolution, meaning an arch rotated around its central vertical axis. The terminology used has been a source of controversy, with inconsistency between scholars and within individual texts, but the term "dome" may be considered a "blanket-word to describe an hemispherical or similar spanning element." A half-dome or semi-dome is a semi-circular shape used in apses. Sometimes called "false" domes, corbel domes achieve their shape by extending each horizontal layer of stones inward farther than the lower one until they meet at the top. A "false" dome may refer to a wooden dome. "True" domes are said to be those whose structure is in a state of compression, with constituent elements of wedge-shaped voussoirs, the joints of which align with a central point. The validity of this is unclear, as domes built underground with corbelled stone layers are in compression from the surrounding earth; the Italian use of the term finto, meaning "false", can be traced back to the 17th century in the use of vaulting made of reed mats and gypsum mortar.
As with arches, the "springing" of a dome is the level. The top of a dome is the "crown"; the inner side of a dome is called the "intrados" and the outer side is called the "extrados". The "haunch" is the part of an arch that lies halfway between the base and the top; the word "cupola" is another word for "dome", is used for a small dome upon a roof or turret. "Cupola" has been used to describe the inner side of a dome. Drums called tholobates, are cylindrical or polygonal walls with or without windows that support a dome. A tambour or lantern is the equivalent structure over a dome's oculus. A masonry dome outward, they are thought of in terms of two kinds of forces at right angles from one another. Meridional forces are compressive only, increase towards the base, while hoop forces are in compression at the top and tension at the base, with the transition in a hemispherical dome occurring at an angle of 51.8 degrees from the top. The thrusts generated by a dome are directly proportional to the weight of its materials.
Grounded hemispherical domes generate significant horizontal thrusts at their haunches. Unlike voussoir arches, which require support for each element until the keystone is in place, domes are stable during construction as each level is made a complete and self-supporting ring; the upper portion of a masonry dome is always in compression and is supported laterally, so it does not collapse except as a whole unit and a range of deviations from the ideal in this shallow upper cap are stable. Because voussoir domes have lateral support, they can be made much thinner than corresponding arches of the same span. For example, a hemispherical dome can be 2.5 times thinner than a semicircular arch, a dome with the profile of an equilateral arch can be thinner still. The optimal shape for a masonry dome of equal thickness provides for perfect compression, with none of the tension or bending forces against which masonry is weak. For a particular material, the optimal dome geometry is called the funicular surface, the comparable shape in three dimensions to a catenary curve for a two-dimensional arch.
The pointed profiles of many Gothic domes more approximate this optimal shape than do hemispheres, which were favored by Roman and Byza
Lal Masjid, Delhi
Lal Masjid of Delhi known as the Fakr-ul Masjid or Sikandar Sahib's Masjid, is a mosque located in Bara Bazaar, Kashmiri Gate in Old Delhi, India. The building was built in 1728 by Kaniz-i-Fatima, in memory of her husband Shujaat Khan, a noble in the court of Mughal emperor Aurangzeb. Colonel James Skinner repaired its construction is sometimes misattributed to him. Illustrations and descriptions of the mosque were included in Sir Thomas Metcalfe's 1844 book "Reminiscences of Imperial Delhi." In the 1857 Siege of Delhi the mosque was damaged, yet since has been repaired. The mosque sits on a raised plinth of about 12 metres by 7.3 metres and stands 2.5 metres above the adjacent shop-lined streets. The main complex consists of three rooms each with its own arched entryway. Two striped towers on either side of the center arch are mirrored by the mosque's two minarets standing at the rear corners of building. Behind a decorated parapet on the roof of the mosque sit three black marble domes; the building's prominent use of red sandstone and white marble is considered unusual for the period, though many of its other features, including its minarets and domes, are modeled off of the major mosques of Delhi including the nearby Jama Masjid
Hazratbal Shrine, Srinagar
The Hazratbal Shrine is a Muslim shrine in Hazratbal, Srinagar and Kashmir, India. It contains the Moi-e-Muqqadas, believed by many Muslims of Kashmir to be Muhammad's hair; the name of the shrine comes from the Urdu word Hazrat, meaning "respected", the Kashmiri word bal, meaning "place". Thus it means the place, given high regards and is respected among the people; the shrine is situated on the Northern bank of the Dal Lake, is considered to be Kashmir's holiest Muslim shrine. According to legend, the mosque contained strands of Muhammad's hair referred to as "the relic of Hazratbal shrine" or "the relic"; the relic was first brought to Kashmir by Syed Abdullah, a purported descendant of Muhammad who left Medina and settled in Bijapur, near Hyderabad in 1635. When Syed Abdullah died, his son Syed Hamid inherited the relic. Following the Mughal conquest of the region, Syed Hamid was stripped of his family estates. Finding himself unable to care for the relic, he sold it to a wealthy Kashmiri businessman Khwaja Nur-ud-Din Eshai.
However, when the Mughal Emperor Aurangzeb came to know of what had transpired, he had the relic seized and sent to the shrine of Khwaja Moinuddin Chishti at Ajmer, had Khwaja Nur-ud-Din Eshai imprisoned in Delhi for possessing the relic. Realizing his mistake, Aurangzeb decided to restore the relic to Khwaja Nur-ud-Din Eshai and to allow him to take it to Kashmir. However, Khwaja Nur-ud-Din Eshai had died in imprisonment. In 1700, the relic reached Kashmir, along with the body of Khwaja Nur-ud-Din Eshai. There, Inayat Begum, daughter of Khwaja Nur-ud-Din Eshai, became a custodian of the relic and established the shrine. Since her male descendants have been caretakers of the relic; the relic was reported to have disappeared on 27 December 1963. There were mass protests all over the state on the disappearance of the Moi-e-Muqaddas with hundreds of thousands out in the streets; the Awami Action Committee was formed to recover the relic. On 31 December, Indian Prime Minister Jawaharlal Nehru made a broadcast to the nation on the disappearance of the sacred relic.
The relic was recovered on 4 January 1964. Ziyarat Naqshband Sahab Hamza Makhdoom Khanqah-e-Moula Dastgeer Sahib
Jamia Masjid, Srinagar
Jamia Masjid is a mosque in Srinagar, Jammu & Kashmir, India. Situated at Nowhatta in the middle of the Old City, the Mosque was commissioned by Sultan Sikandar in 1394 CE and completed in 1402 CE, at the behest of Mir Mohammad Hamadani, son of Mir Sayyid Ali Hamadani, is regarded as one of the most important mosques in Kashmir; the architectural style of the Mosque is inspired by the Indo-Saracenic style of architecture, a blend of Indian and Mughal styles, bears similarities to Buddhist pagodas. The Mosque is located in Downtown which remains a central zone to the religio-political life in Srinagar. Thronged by Muslims every Friday, it is one of the prime tourist attractions of Srinagar; the Jamia Masjid is influenced by the Indo-Saracenic style of architecture and has been constructed in the Persian manner, with some similarities to the Buddhist pagodas. The structure occupies a total area of 384 x 381 feet and is quadrangular in shape with four turrets; these are in the middle of each side and covered with pyramidal roofs.
All of the turrets are interconnected by spacious halls, with bright yellow poppies lining the mossy brick paths and the entire structure is surrounded by wide lanes on all four sides and has a square garden in the middle. The entrance on the southern side of the Mosque comprises a recessed portico which further leads onto an inner courtyard; this courtyard has a tank in the centre. The entire courtyard is made up of brick arcade; the court, planted with a series of chinars is enclosed by arched liwans covered with two tiered sloping roof. It is not only the religion; the Jamia Masjid has been a hot-bed of raging political discourse on the present turmoil in the state, the politics that has unfolded in Kashmir has led to curbs and gags on congregations here. Its roots, lie deeper in history; the Mosque became a platform for people to debate and discuss the politics of the Kashmir conflict much earlier before the conflict erupted in Kashmir valley. According to historian Mohammad Ishaq Khan, “Jamia Masjid has played a significant part in imparting religious education.
However, with the spread of modern education among Kashmiri Muslims, thanks to the efforts of Mirwaiz Ghulam Rasul Shah, the Masjid began to play a seminal role in the growth of political consciousness. Sheikh Muhammad Abdullah was, in fact, initiated into what I would call the mysteries of Kashmiri Muslim politics at Jamia Masjid by Mirwaiz Muhammad Yusuf Shah.” For 21 years, the Mosque faced closure under the Sikh regime of Maharaja Ranjit Singh beginning in 1819 AD, when the-then Governor, Moti Ram, put curbs on offering prayers in Jamia Masjid. No prayers were offered and no call for prayers was given from the Mosque, it was reopened by Sikh Governor, Ghulam Muhi-ud-Din, in 1843 who spent nearly a lakh and a half of rupees on its repair. But for 11 years, rulers allowed prayers only on Fridays; the Mosque closed again. The martyrs of July 13, 1931 were taken to Jamia Masjid after the police opened fire and 22 people were killed and hundreds injured; the bodies of the martyrs were laid in the compound of Jamia Masjid where Sheikh Abdullah, Mirwaiz Maulvi Muhammad Yusuf Shah and other leaders started delivering speeches against Maharaja Hari Singh.
Prolonged closure of the Mosque once again came into effect since 2008 when the Amarnath land row erupted. The decision of the Omar Abdullah government to prevent people from offering Friday prayers for weeks together led to massive outrage. Ban on religious congregations in 2008 was seen as an attempt to choke the rebellion whose epicentre was the hotbed of separatist leaders, the areas in old city around Jamia Masjid. During the Mehbooba Mufti led BJP-PDP coalition government, the Mosque was again "locked down for three months in the uprising of 2016 and in 2017 for the first time Jumat-ul-Vida congregation during Ramadan was not allowed and in 2018 for 16 Fridays, prayers were barred at the Mosque." On the western and eastern sides, the Mosque is 381 feet in length while the northern and southern sides are 384 feet long. The inner courtyard measures 375 feet x 370 feet having a 33 feet x 34 feet water tank with a fountain flowing in the centre, thus the space area of the Mosque is 146,000 square feet.
Its walls made of burnt bricks are over 4 feet thick. The lower portion of the walls is made of rectangular stones. There are three big entrance gates on north and eastern sides of the Mosque confronting three turrets standing on lofty columns of deodar wood; the eastern side has a large entrance called the Shah Gate, covered with a pyramidical roof surmounted by a square open pavilion with a spire on top. A total of 378 wooden columns support the roof; each turret is supported by eight lofty pillars 6 feet in girth. The mihrab too has a similar turret over it; the remaining interior of the Mosque has 346 columns 5 feet in girth. The roof was covered with birch bark and clay; the western wall of the cloister has a mihrab made of black Kashmiri marble, adorned with beautiful calligraphic work and has engraved on it ninety-nine attributes of Almighty Allah. The Mosque can hold 33,333 persons besides the Imam at a single prayer congregation. To reach the Mosque roof, the walls of the four turrets have interior stairs in the circular form that end in the lounges of each turret.
The city of Srinagar can be viewed from these high turrets. The roof is constructed out of timber and iron bars
Narendra Damodardas Modi is an Indian politician serving as the 14th and current Prime Minister of India since 2014. He was the Chief Minister of Gujarat from 2001 to 2014, is the Member of Parliament for Varanasi. Modi is a member of the Bharatiya Janata Party, of the Rashtriya Swayamsevak Sangh, a Hindu nationalist volunteer organisation. Born to a Gujarati family in Vadnagar, Modi helped his father sell tea as a child, has said he ran his own stall, he was introduced to the RSS at the age of eight, beginning a long association with the organisation. Modi left home after finishing high-school in part due to an arranged marriage to Jashodaben Chimanlal, which he abandoned, publicly acknowledged only many decades later. Modi travelled around India for two years and visited a number of religious centres before returning to Gujarat. In 1971 he became a full-time worker for the RSS. During the state of emergency imposed across the country in 1975, Modi was forced to go into hiding; the RSS assigned him to the BJP in 1985, he held several positions within the party hierarchy until 2001, rising to the rank of General Secretary.
Modi was appointed Chief Minister of Gujarat in 2001, due to Keshubhai Patel's failing health and poor public image following the earthquake in Bhuj. Modi was elected to the legislative assembly soon after, his administration has been considered complicit in the 2002 Gujarat riots, or otherwise criticised for its handling of it. A Supreme Court-appointed Special Investigation Team found no evidence to initiate prosecution proceedings against Modi personally, his policies as chief minister, credited with encouraging economic growth, have received praise. His administration has been criticised for failing to improve health and education indices in the state. Modi led the BJP in the 2014 general election, which gave the party a majority in the Indian lower house of parliament, the Lok Sabha, the first time for any single party since 1984. Modi's administration has tried to raise foreign direct investment in the Indian economy, reduced spending on healthcare and social welfare programmes. Modi has attempted to improve efficiency in the bureaucracy.
He began a high-profile sanitation campaign, weakened or abolished environmental and labour laws. He initiated a controversial demonetisation of high-denomination banknotes. Described as engineering a political realignment towards right-wing politics, Modi remains a figure of controversy domestically and internationally over his Hindu nationalist beliefs and his role during the 2002 Gujarat riots, cited as evidence of an exclusionary social agenda. Narendra Modi was born on 17 September 1950 to a family of grocers in Vadnagar, Mehsana district, Bombay State, he was the third of six children born to Damodardas Mulchand Hiraben Modi. Modi's family belonged to the Modh-Ghanchi-Teli community, categorised as an Other Backward Class by the Indian government; as a child, Modi helped his father sell tea at the Vadnagar railway station, said that he ran a tea stall with his brother near a bus terminus. Modi completed his higher secondary education in Vadnagar in 1967, where a teacher described him as an average student and a keen debater, with interest in theatre.
Modi had an early gift for rhetoric in debates, his teachers and students noted this. Modi preferred playing larger-than-life characters in theatrical productions, which has influenced his political image; when eight years old, Modi discovered the Rashtriya Swayamsevak Sangh and began attending its local shakhas. There, Modi met Lakshmanrao Inamdar, popularly known as Vakil Saheb, who inducted him as a balswayamsevak in the RSS and became his political mentor. While Modi was training with the RSS, he met Vasant Gajendragadkar and Nathalal Jaghda, Bharatiya Jana Sangh leaders who were founding members of the BJP's Gujarat unit in 1980. In Narendra Modi's childhood, in a custom traditional to his caste, his family arranged a betrothal to a girl, Jashodaben Chimanlal, leading to their marriage when they were teenagers. Sometime thereafter, he abandoned the further marital obligations implicit in the custom, left home, the couple going on to lead separate lives, neither marrying again, the marriage itself remaining unmentioned in Modi's public pronouncements for many decades.
In April 2014, shortly before the national elections that swept him to power, Modi publicly affirmed that he was married and his spouse was Ms Chimanlal. Modi spent the ensuing two years travelling across Northern and North-eastern India, though few details of where he went have emerged. In interviews, Modi has described visiting Hindu ashrams founded by Swami Vivekananda: the Belur Math near Kolkata, followed by the Advaita Ashrama in Almora and the Ramakrishna Mission in Rajkot. Modi remained only a short time at each. Vivekananda has been described as a large influence in Modi's life. In the early summer of 1968, Modi reached the Belur Math but was turned away, after which Modi wandered through Calcutta, West Bengal and Assam, stopping in Siliguri and Guwahati. Modi went to the Ramakrishna Ashram in Almora, where he was again rejected, before travelling back to Gujarat via Delhi and Rajasthan in 1968–69. Sometime in late 1969 or early 1970, Modi returned to Vadnagar for a brief visit before leaving again for Ahmedabad.
There, Modi lived with his uncle, working in the latter's canteen at the Gujarat State Road Transport Corporation. In Ahmedabad, Modi r
The Kolkata Metro is a rapid transit system serving the Kolkata metropolitan area in the Indian state of West Bengal. The network consists of one operational line of 27.22 km from Noapara to Kavi Subhash with five other lines in various phases of construction. The Kolkata Metro was the first metro railway in India, opening for commercial services from 1984, it is the sixth longest operational metro network in India after the Delhi Metro, Hyderabad Metro, Chennai Metro, Namma Metro and Noida Metro. On 29 December 2010, Metro Railway, Kolkata became the 17th zone of the Indian Railways, operated by the Ministry of Railways. There are 300 metro services daily carrying over 700,000 passengers making it the second busiest metro system in India. An East-West railway connection for the city was proposed in 1921 by Harley Dalrymple-Hay during the British Raj, but it was not undertaken due to a lack of funds; the Chief Minister of West Bengal, Dr. Bidhan Chandra Roy, reconceived the idea of building an Underground Railway for Kolkata in the early 1950s.
A survey was done by a team of French experts. Efforts to solve the problem by augmenting the existing fleet of public transport vehicles hardly helped, since roads accounted for only 4.2% of the surface area in Kolkata, compared with 25% in Delhi and 30% in other cities. With the goal of finding alternative solutions to alleviate the suffering of commuters, the Metropolitan Transport Project was set up in 1969; the MTP, with help of Soviet specialists and East German engineers, prepared a master plan to provide five rapid-transit lines for the city of Kolkata, totalling a route length of 97.5 km in 1971. However, only three were selected for construction; these were: Dum Dum - Tollygunge Salt Lake City - Ramrajatala Dakshineshwar - Thakurpukur Of these, the highest priority was given to the busy north-south axis between Dum Dum and Tollygunge over a length of 16.45 km, the work on this project was sanctioned on 1 June 1972. The foundation stone of the project was laid by Indira Gandhi, the Prime Minister of India, on 29 December 1972 and the construction work started in 1973-74.
In those early days of Kolkata Metro, the planning, thought processing, political facilitation of the whole project was borne single-handedly by the Union Railway Minister from West Bengal - A. B. A. Ghani Khan Choudhury - against the prevailing socio-political stance of his contemporaries in the West Bengal government. From the start of construction, the project had to contend with several problems including insufficient funds, a shifting of underground utilities, court injunctions, an irregular supply of vital materials. Despite the difficulties faced, services began on 24 October 1984, with the commissioning of a partial commercial service covering a distance of 3.40 km with five stations served in between Esplanade and Bhowanipur. The first metro was driven by Tapan Kumar Sanjoy Sil; the service was followed by commuter services on another 2.15 km stretch in the north between Dum Dum and Belgachhia on 12 November 1984. The commuter service was extended up to Tollygunge on 29 April 1986 covering a further distance of 4.24 km making the service available over a distance of 9.79 km and covering 11 stations.
However, the services on the north section were suspended with effect from 26 October 1992, as this isolated small section was little used. After a gap of more than eight years, the 1.62 km Belgachhia-Shyambazaar section, along with the Dum Dum-Belgachhia stretch, was opened on 13 August 1994. Another 0.71 km stretch from Esplanade to Chandni Chowk was commissioned shortly afterwards, on 2 October 1994. The Shyambazaar-Shobhabazar-Girish Park and Chandni Chowk-Central sections were opened on 19 February 1995. Services on the entire stretch of the Metro were introduced from 27 September 1995 by bridging the vital gap of 1.80 km in the middle. In the final stage, the extension of Line 1 to an elevated corridor from Tollygunge to New Garia was constructed and opened in two phases, Mahanayak Uttam Kumar to Kavi Nazrul in 2009 and Kavi Nazrul to Kavi Subhash in 2010; the latest extension constructed was the 2.59 km elevated corridor from Dum Dum to Noapara on 10 July 2013. In 2009, a large number of stations on Line 1 were renamed by Minister of Railways Mamata Banerjee, who hails from Kolkata.
The state government has prepared a detailed project report on a proposed extension of East West Metro from Howrah Maidan to Santragachhi. Rites, the implementing agency for the 10 km East-West Metro extension project from Howrah Maidan to Santragachhi bus terminus, is set to start work on the corridor early in 2017. In 2010, the Railway Ministry announced plans for the construction of five new metro lines and an extension of the existing North-South corridor; these new projects are: Salt Lake City - Howrah Maidan Joka - BBD Bagh Noapara - Barasat via Biman Bandar Baranagar - Barrackpore Noapara - Dakshineswar New Garia - Biman Bandar Extension of Line 1 from Dum Dum to Dakshineshwar via Noapara Construction of station at Noapara: A new 4-platform station has been constructed at Noapara. Commuters of Line 1 will be able to interchange trains going towards the Airport via Line 4. For the time being only two platforms are in use, but once Line 4 gets started, all four platforms will become operational.
Upgrade of Esplanade metro station: A subway is going to be constructed in the existing Esp
2004 Indian Ocean earthquake and tsunami
The 2004 Indian Ocean earthquake occurred at 00:58:53 UTC on 26 December, with an epicentre off the west coast of northern Sumatra. It was an undersea megathrust earthquake that registered a magnitude of 9.1–9.3 Mw, reaching a Mercalli intensity up to IX in certain areas. The earthquake was caused by a rupture along the fault between the Indian Plate. A series of large tsunamis up to 30 metres high were created by the underwater seismic activity that became known collectively as the Boxing Day tsunamis. Communities along the surrounding coasts of the Indian Ocean were affected, the tsunamis killed an estimated 227,898 people in 14 countries; the Indonesian city of Banda Aceh reported the largest number of victims. The earthquake was one of the deadliest natural disasters in recorded history; the direct results caused major disruptions to living conditions and commerce in Indonesia, Sri Lanka and Thailand. The earthquake was the third largest recorded and had the longest duration of faulting observed.
It caused the planet to vibrate as much as 1 centimetre, it remotely triggered earthquakes as far away as Alaska. Its epicentre was between mainland Sumatra; the plight of the affected people and countries prompted a worldwide humanitarian response, with donations totaling more than US$14 billion. The event is known by the scientific community as the Sumatra–Andaman earthquake; the 2004 Indian Ocean earthquake was documented as having a moment magnitude of 8.8. In February 2005, scientists revised the estimate of the magnitude to 9.0. Although the Pacific Tsunami Warning Center has accepted these new numbers, the United States Geological Survey has so far not changed its estimate of 9.1. A 2006 study estimated a magnitude of Mw 9.1–9.3. The hypocentre of the main earthquake was 160 km off the western coast of northern Sumatra, in the Indian Ocean just north of Simeulue island at a depth of 30 km below mean sea level; the northern section of the Sunda megathrust ruptured over a length of 1,300 km.
The earthquake was felt in Bangladesh, Malaysia, Thailand, Sri Lanka and the Maldives. Splay faults, or secondary "pop up faults", caused long, narrow parts of the sea floor to pop up in seconds; this elevated the height and increased the speed of waves, destroying the nearby Indonesian town of Lhoknga. Indonesia lies between the Pacific Ring of Fire along the north-eastern islands adjacent to New Guinea, the Alpide belt that runs along the south and west from Sumatra, Bali, Flores to Timor; the 2002 Sumatra earthquake is believed to have been a foreshock, preceding the main event by over two years. Great earthquakes, such as the 2004 Indian Ocean earthquake, are associated with megathrust events in subduction zones, their seismic moments can account for a significant fraction of the global seismic moment across century-scale time periods. Of all the moment released by earthquakes in the 100 years from 1906 through 2005 one-eighth was due to the 2004 Indian Ocean earthquake; this quake, together with the Good Friday earthquake and the Great Chilean earthquake, account for half of the total moment.
Since 1900, the only earthquakes recorded with a greater magnitude were the 1960 Great Chilean earthquake and the 1964 Good Friday earthquake in Prince William Sound. The only other recorded earthquakes of magnitude 9.0 or greater were off Kamchatka, Russia, on 4 November 1952 and Tōhoku, Japan in March 2011. Each of these megathrust earthquakes spawned tsunamis in the Pacific Ocean. However, in comparison to the 2004 Indian Ocean earthquake, the death toll from these earthquakes was lower because of the lower population density along the coasts near affected areas, the much greater distances to more populated coasts, the superior infrastructure and warning systems in MEDCs such as Japan. Other large megathrust earthquakes occurred in 1868. All of them are believed to be greater than magnitude 9, but no accurate measurements were available at the time; the 2004 Indian Ocean earthquake was unusually large in geological extent. An estimated 1,600 kilometres of fault surface slipped about 15 metres along the subduction zone where the Indian Plate slides under the overriding Burma Plate.
The slip did not happen instantaneously but took place in two phases over several minutes: Seismographic and acoustic data indicate that the first phase involved a rupture about 400 kilometres long and 100 kilometres wide, 30 kilometres beneath the sea bed—the largest rupture known to have been caused by an earthquake. The rupture proceeded at about 2.8 kilometres per second, beginning off the coast of Aceh and proceeding north-westerly over about 100 seconds. After a pause of about another 100 seconds, the rupture continued northwards towards the Andaman and Nicobar Islands. However, the northern rupture occurred more than in the south, at about 2.1 km/s, continuing north for another five minutes to a plate boundary where the fault t