Misplaced Pages

France–Seychelles Maritime Boundary Agreement

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

The France–Seychelles Maritime Boundary Agreement is a 2001 treaty between France and Seychelles which delimits the maritime boundary between Seychelles and the uninhabited Glorioso Islands , which is a French possession.

#296703

80-515: The treaty was signed in Victoria , Seychelles on 19 February 2001. The boundary set out by the text of the treaty identifies two straight-line maritime segments defined by three individual coordinate points. The boundary is an approximately equidistant line between the two territories. The north end of the boundary stops short of the tripoint with the Comoros and the south end stops short of

160-663: A line source ). This greatly increased the geographical area over which the waves were observed, reaching as far as Mexico, Chile, and the Arctic. The raising of the seafloor significantly reduced the capacity of the Indian Ocean, producing a permanent rise in the global sea level by an estimated 0.1 mm (0.004 in). Numerous aftershocks were reported off the Andaman Islands , the Nicobar Islands and

240-466: A 2.6 m (8.5 ft) crest-to-trough tsunami was measured. As well, the tsunami was large enough to be detected in Vancouver , which puzzled many scientists, as the tsunamis measured in some parts of South America were larger than those measured in some parts of the Indian Ocean. It has been theorized that the tsunamis were focused and directed at long ranges by the mid-ocean ridges which run along

320-480: A busload of vacationers and locals to safety on higher ground. Anthropologists had initially expected the aboriginal population of the Andaman Islands to be badly affected by the tsunami and even feared the already depopulated Onge tribe could have been wiped out. Many of the aboriginal tribes evacuated and suffered fewer casualties, however. Oral traditions developed from previous earthquakes helped

400-618: A causal relationship between these events. The 2004 Indian Ocean earthquake is thought to have triggered activity in both Leuser Mountain and Mount Talang , volcanoes in Aceh along the same range of peaks, while the 2005 Nias–Simeulue earthquake sparked activity in Lake Toba , a massive caldera in Sumatra. The energy released on the Earth's surface ( M e , the energy magnitude, which

480-479: A few mosques remained standing. The greatest run-up height of the tsunami was measured at a hill between Lhoknga and Leupung , on the western coast of the northern tip of Sumatra, near Banda Aceh, and reached 51 m (167 ft). The tsunami heights in Sumatra: The island country of Sri Lanka, located about 1,700 km (1,100 mi) from Sumatra, was ravaged by the tsunami around two hours after

560-442: A landmass between them and the tsunami's location of origin are usually safe; however, tsunami waves can sometimes diffract around such landmasses. Thus, the state of Kerala was hit by the tsunami despite being on the western coast of India, and the western coast of Sri Lanka suffered substantial impacts. Distance alone was no guarantee of safety, as Somalia was hit harder than Bangladesh despite being much farther away. Because of

640-453: A large turbulent bore. Eyewitnesses described the tsunami as a "black giant", "mountain" and a "wall of water". Video footage revealed torrents of black water, surging by windows of a two-story residential area situated about 3.2 km (2.0 mi) inland. Additionally, amateur footage recorded in the middle of the city captured an approaching black surge flowing down the city streets, full of debris, inundating them. The level of destruction

720-441: A low, broad hump, barely noticeable and harmless, which generally travels at the high speed of 500 to 1,000 km/h (310 to 620 mph); in shallow water near coastlines, a tsunami slows down to only tens of kilometres per hour but, in doing so, forms large destructive waves. Scientists investigating the damage in Aceh found evidence that the wave reached a height of 24 m (80 ft) when coming ashore along large stretches of

800-401: A magnitude of as high as 6.9 ) and presently ranks as the third-largest earthquake ever recorded on the moment magnitude or Richter scale . Other aftershocks of up to magnitude 7.2 continued to shake the region daily for three or four months. As well as continuing aftershocks, the energy released by the original earthquake continued to make its presence felt well after the event. A week after

880-638: A major earthquake with a magnitude of 9.2–9.3 M w struck with an epicentre off the west coast of northern Sumatra , Indonesia. The undersea megathrust earthquake , known by the scientific community as the Sumatra–Andaman earthquake , was caused by a rupture along the fault between the Burma plate and the Indian plate , and reached a Mercalli intensity of IX in some areas. A massive tsunami with waves up to 30 m (100 ft) high, known as

SECTION 10

#1732779991297

960-447: A major earthquake under ordinary circumstances but is dwarfed by the mainshock . The shift of mass and the massive release of energy slightly altered the Earth's rotation. Weeks after the earthquake, theoretical models suggested the earthquake shortened the length of a day by 2.68 microseconds , due to a decrease in the oblateness of the Earth. It also caused the Earth to minutely "wobble" on its axis by up to 25 mm (1 in) in

1040-486: A month after the earthquake found the movement to be about 0.2 m (8 in). Since movement was vertical as well as lateral, some coastal areas may have been moved to below sea level. The Andaman and Nicobar Islands appear to have shifted south-west by around 1.25 m (4 ft 1 in) and to have sunk by 1 m (3 ft 3 in). In February 2005, the Royal Navy vessel HMS  Scott surveyed

1120-617: A network of sensors is needed to detect it. Tsunamis are more frequent in the Pacific Ocean than in other oceans because of earthquakes in the " Ring of Fire ". Although the extreme western edge of the Ring of Fire extends into the Indian Ocean (the point where the earthquake struck), no warning system exists in that ocean. Tsunamis there are relatively rare despite earthquakes being relatively frequent in Indonesia. The last major tsunami

1200-423: A single block of rock some 100 m (330 ft) high and 2 km (1.2 mi) long. The momentum of the water displaced by tectonic uplift had also dragged massive slabs of rock, each weighing millions of tonnes, as far as 10 km (6 mi) across the seabed. An oceanic trench several kilometres wide was exposed in the earthquake zone. The TOPEX/Poseidon and Jason-1 satellites happened to pass over

1280-524: Is twinned with: Victoria features a tropical rainforest climate ( Köppen climate classification Af ) with high temperatures throughout the course of the year. The capital does have noticeably wetter and drier periods during the year, with June and July being its driest months and December through February being the city's wettest months. However, since in no month does the average monthly precipitation falls below 60 millimetres or 2.4 inches in Victoria,

1360-434: 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 periods. Of all the moment released by earthquakes in the 100 years from 1906 through 2005, roughly one eighth

1440-1004: Is in Victoria. Attractions in the city include a clocktower modelled on Little Ben in London, the courthouse, the Botanical Gardens , the National Museum of History , the Natural History Museum and the Sir Selwyn Selwyn-Clarke Market. Victoria Market and the brightly coloured fish and fruit markets is the local hot spot for the Seychellois people. There are two cathedrals in Victoria, Immaculate Conception Cathedral ( Roman Catholic ) and St Paul's Cathedral ( Anglican ). There are also Baptist and Pentecostal churches, mosques and Hindu temples. Stade Linité ,

1520-405: Is more than twice the total explosive energy used during all of World War II (including the two atomic bombs) but still a couple of orders of magnitude less than the energy released in the earthquake itself. In many places, the waves reached as far as 2 km (1.2 mi) inland. Because the 1,600 km (1,000 mi) fault affected by the earthquake was in a nearly north–south orientation,

1600-785: Is part of the Indo-Australian plate , which underlies the Indian Ocean and Bay of Bengal , and is moving north-east at an average of 60 mm/a (0.075 in/Ms). The India Plate meets the Burma plate (which is considered a portion of the great Eurasian plate ) at the Sunda Trench . At this point, the India Plate subducts beneath the Burma plate, which carries the Nicobar Islands, the Andaman Islands, and northern Sumatra. The India Plate sinks deeper and deeper beneath

1680-547: Is the seismic potential for damage ) by the 2004 Indian Ocean earthquake was estimated at 1.1 × 10 joules . The earthquake generated a seismic oscillation of the Earth's surface of up to 200–300 mm (8–12 in), equivalent to the effect of the tidal forces caused by the Sun and Moon. The seismic waves of the earthquake were felt across the planet, as far away as the U.S. state of Oklahoma , where vertical movements of 3 mm (0.12 in) were recorded. By February 2005,

SECTION 20

#1732779991297

1760-546: Is the capital and largest city of the Republic of Seychelles , situated on the north-eastern side of Mahé , the archipelago's main island. The city was first established as the seat of the British colonial government. In 2010, the population of Greater Victoria (including the suburbs) was 26,450 (26.66%) out of the country's total population of 99,202. The port is known as Port Victoria . The area that would become Victoria

1840-699: The Boxing Day Tsunami after the Boxing Day holiday, or as the Asian Tsunami , devastated communities along the surrounding coasts of the Indian Ocean, killing an estimated 227,898 people in 14 countries in one of the deadliest natural disasters in recorded history . The direct results caused major disruptions to living conditions and commerce in coastal provinces of surrounded countries, including Aceh (Indonesia), Sri Lanka , Tamil Nadu (India) and Khao Lak (Thailand). Banda Aceh reported

1920-475: The California Institute of Technology estimates that M w  9.2 is best representative of the earthquake's size. More recent studies estimate the magnitude to be M w  9.3. A 2016 study estimated the magnitude to be M w  9.25, while a 2021 study revised its 2007 estimate of M w  9.1 to a new magnitude of M w  9.2. The hypocentre of the main earthquake

2000-659: The Maldives . Splay faults, or secondary "pop up faults", caused long, narrow parts of the seafloor to pop up in seconds. This quickly 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 , and the Alpide belt that runs along the south and west from Sumatra, Java , Bali , Flores to Timor . The 2002 Sumatra earthquake

2080-569: The subduction zone where the Indian plate slides under (or subducts) 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 km (250 mi) long and 100 km (60 mi) wide, 30 km (19 mi) beneath the sea bed—the largest rupture ever known to have been caused by an earthquake. The rupture proceeded at about 2.8 km/s (1.74 mi/s; 10,100 km/h; 6,260 mph), beginning off

2160-471: The Burma plate until the increasing temperature and pressure drive volatiles out of the subducting plate. These volatiles rise into the overlying plate, causing partial melting and the formation of magma. The rising magma intrudes into the crust above and exits the Earth's crust through volcanoes in the form of a volcanic arc . The volcanic activity that results as the Indo-Australian plate subducts

2240-426: The Earth on the vertical axis (note the 1 cm scale bar at the bottom for scale). The seismograms are arranged vertically by distance from the epicentre in degrees. The earliest, lower amplitude signal is that of the compressional (P) wave , which takes about 22 minutes to reach the other side of the planet (the antipode ; in this case near Ecuador). The largest amplitude signals are seismic surface waves that reach

2320-518: The Eurasian plate has created the Sunda Arc . As well as the sideways movement between the plates, the 2004 Indian Ocean earthquake resulted in a rise of the seafloor by several metres, displacing an estimated 30 km (7.2 cu mi) of water and triggering devastating tsunami waves. The waves radiated outwards along the entire 1,600 km (1,000 mi) length of the rupture (acting as

2400-468: The Pacific Ocean. In comparison to the 2004 Indian Ocean earthquake, the death toll from these earthquakes and tsunamis was significantly lower, primarily because of the lower population density along the coasts near affected areas. Comparisons with earlier earthquakes are difficult, as earthquake strength was not measured systematically until the 1930s. However, historical earthquake strength can sometimes be estimated by examining historical descriptions of

2480-509: The aboriginal tribes escape the tsunami. For example, the folklore of the Onges talks of "huge shaking of ground followed by high wall of water". Almost all of the Onge people seemed to have survived the tsunami. The tsunami devastated the coastline of Aceh province, about 20 minutes after the earthquake. Banda Aceh , the closest major city, suffered severe casualties. The sea receded and exposed

France–Seychelles Maritime Boundary Agreement - Misplaced Pages Continue

2560-456: The antipode after about 100 minutes. The surface waves can be clearly seen to reinforce near the antipode (with the closest seismic stations in Ecuador), and to subsequently encircle the planet to return to the epicentral region after about 200 minutes. A major aftershock (magnitude 7.1) can be seen at the closest stations starting just after the 200-minute mark. The aftershock would be considered

2640-401: The capital city. The tsunami reached a run-up of 10–20 m (33–66 ft) on the western shorelines of Breueh Island and Nasi Island . Coastal villages were destroyed by the waves. On Weh Island , strong surges were experienced in the port of Sabang , yet there was little damage with reported runup values of 3–5 m (9.8–16.4 ft), most likely due to the island being sheltered from

2720-624: The city does not have a true dry season month. This lack of a true dry season month is a primary reason why the climate falls under the tropical rainforest climate category. The capital averages about 2,300 millimetres or 91 inches of rainfall annually. Although being very rainy, skies are usually clear to partly clear and completely cloudy days remain scarce throughout the year even during the rainiest months. 4°37′23″S 55°27′09″E  /  4.6231°S 55.4525°E  / -4.6231; 55.4525 2004 Indian Ocean earthquake On 26 December 2004, at 07:58:53 local time ( UTC+7 ),

2800-588: The city was just at the level of the second floor, and there were large amounts of debris piled along the streets and in the ground-floor storefronts. In the seaside section of Ulee Lheue, the flow depths were over 9 m (30 ft). Footage showed evidence of back-flowing of the Aceh River , carrying debris and people from destroyed villages at the coast and transporting them up to 40 km (25 mi) inland. A group of small islands: Weh, Breueh, Nasi, Teunom , Bunta , Lumpat , and Batee lie just north of

2880-467: The coast and appeared like gigantic surfing waves but "taller than the coconut trees and was like a mountain". The second wave was the largest; it came from the west-southwest within five minutes of the first wave. The tsunami stranded cargo ships, barges and destroyed a cement mining facility near the Lampuuk coast, where it reached the fourth level of the building. Meulaboh , a remote coastal city,

2960-590: 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 . The northern rupture occurred more slowly than in the south, at about 2.1 km/s (1.3 mi/s; 7,600 km/h; 4,700 mph), continuing north for another five minutes to a plate boundary where the fault type changes from subduction to strike-slip (the two plates slide past one another in opposite directions). The Indian plate

3040-516: The coastline, rising to 30 m (100 ft) in some areas when travelling inland. Radar satellites recorded the heights of tsunami waves in deep water: the maximum height was at 600 mm (2 ft) two hours after the earthquake, the first such observations ever made. According to Tad Murty , vice-president of the Tsunami Society, the total energy of the tsunami waves was equivalent to about 5 megatons of TNT (21  PJ ), which

3120-508: The damage caused, and the geological records of the areas where they occurred. Some examples of significant historical megathrust earthquakes are the 1868 Arica earthquake in Peru and the 1700 Cascadia earthquake in western North America. The 2004 Indian Ocean earthquake was unusually large in geographical and geological extent. An estimated 1,600 km (1,000 mi) of fault surface slipped (or ruptured) about 15 m (50 ft) along

3200-446: The direct attack by the islands to the south-west. Lhoknga is a small coastal community about 13 km (8.1 mi) south-west of Banda Aceh, located on a flat coastal plain in between two rainforest -covered hills, overlooking a large bay and famous for its large swathe of white sandy beach and surfing activities. The locals reported 10 to 12 waves, with the second and third being the highest and most destructive. Interviews with

3280-461: The direction of 145° east longitude , or perhaps by up to 50 or 60 mm (2.0 or 2.4 in). Because of tidal effects of the Moon, the length of a day increases at an average of 15 microseconds per year, so any rotational change due to the earthquake will be lost quickly. Similarly, the natural Chandler wobble of the Earth, which in some cases can be up to 15 m (50 ft), eventually offset

France–Seychelles Maritime Boundary Agreement - Misplaced Pages Continue

3360-463: The distances involved, the tsunami took anywhere from fifteen minutes to seven hours to reach the coastlines. The northern regions of the Indonesian island of Sumatra were hit quickly, while Sri Lanka and the east coast of India were hit roughly 90 minutes to two hours later. Thailand was struck about two hours later despite being closer to the epicentre because the tsunami travelled more slowly in

3440-412: The earthquake's effects were still detectable as a 20 μm (0.02 mm; 0.0008 in) complex harmonic oscillation of the Earth's surface, which gradually diminished and merged with the incessant free oscillation of the Earth more than four months after the earthquake. Because of its enormous energy release and shallow rupture depth, the earthquake generated remarkable seismic ground motions around

3520-496: The earthquake, its reverberations could still be measured, providing valuable scientific data about the Earth's interior. The 2004 Indian Ocean earthquake came just three days after a magnitude 8.1 earthquake in the sub-antarctic Auckland Islands , an uninhabited region west of New Zealand, and Macquarie Island to Australia's north. This is unusual since earthquakes of magnitude eight or more occur only about once per year on average. The U.S. Geological Survey sees no evidence of

3600-499: The earthquake. The tsunami first struck the eastern coastline and subsequently refracted around the southern point of Sri Lanka ( Dondra Head ). The refracted tsunami waves then inundated the southwestern part of Sri Lanka after some of its energy was reflected from impact with the Maldives. In Sri Lanka, the civilian casualties were second only to those in Indonesia, with approximately 35,000 killed. The eastern shores of Sri Lanka were

3680-501: The first level of a hotel, causing destruction and taking people unaware. Other videos recorded showed that the tsunami appeared like a flood raging inland. The construction of seawalls and breakwaters reduced the power of waves at some locations. The largest run-up measured was at 12.5 m (41 ft) with inundation distance of 390–1,500 m (1,280–4,920 ft) in Yala . In Hambantota , run-ups measured 11 m (36 ft) with

3760-517: The globe, particularly due to huge Rayleigh (surface) elastic waves that exceeded 10 mm (0.4 in) in vertical amplitude everywhere on Earth. The record section plot displays vertical displacements of the Earth's surface recorded by seismometers from the IRIS/USGS Global Seismographic Network plotted with respect to time (since the earthquake initiation) on the horizontal axis, and vertical displacements of

3840-488: The greatest inundation distance of 2 km (1.2 mi). Run-up measurements along the Sri Lankan coasts are at 2.4–4.11 m (7 ft 10 in – 13 ft 6 in). Waves measured on the east coast ranged from 4.5–9 m (15–30 ft) at Pottuvill to Batticaloa at 2.6–5 m (8 ft 6 in – 16 ft 5 in) in the north-east around Trincomalee and 4–5 m (13–16 ft) in

3920-468: The greatest strength of the tsunami waves was in an east–west direction. Bangladesh , which lies at the northern end of the Bay of Bengal , had few casualties despite being a low-lying country relatively near the epicentre. It also benefited from the fact that the earthquake proceeded more slowly in the northern rupture zone, greatly reducing the energy of the water displacements in that region. Coasts that have

4000-461: The hardest hit since it faced the epicentre of the earthquake, while the southwestern shores were hit later, but the death toll was just as severe. The southwestern shores are a hotspot for tourists and fishing. The degradation of the natural environment in Sri Lanka contributed to the high death tolls. Approximately 90,000 buildings and many wooden houses were destroyed. The tsunami arrived on

4080-442: The island as a small brown-orange-coloured flood. Moments later, the ocean floor was exposed as much as 1 km (0.62 mi) in places, which was followed by massive second and third waves. Amateur video recorded at the city of Galle showed a large deluge flooding the city, carrying debris and sweeping away people while in the coastal resort town of Beruwala , the tsunami appeared as a huge brown-orange-coloured bore which reached

SECTION 50

#1732779991297

4160-454: The largest number of deaths. It is the deadliest natural disaster of the 21st century , and the worst tsunami disaster in history. It is also the worst natural disaster in the history of Indonesia, Sri Lanka and Thailand. It was the most powerful earthquake ever recorded in Asia, the most powerful earthquake in the 21st century, and at least the third most powerful earthquake ever recorded in

4240-416: The locals revealed that the sea temporarily receded and exposed coral reefs . In the distant horizon, gigantic black waves about 30 m (98 ft) high made explosion-like sounds as they broke and approached the shore. The first wave came rapidly landward from the south-west as a turbulent bore about 0.5–2.5 m (1.6–8.2 ft) high. The second and third waves were 15–30 m (49–98 ft) high at

4320-421: The margins of the continental plates. Despite a delay of up to several hours between the earthquake and the impact of the tsunami, nearly all of the victims were taken by surprise. There were no tsunami warning systems in the Indian Ocean to detect tsunamis or to warn the general population living around the ocean. Tsunami detection is difficult because while a tsunami is in deep water, it has little height and

4400-474: The minor wobble produced by the earthquake. There was 10 m (33 ft) movement laterally and 4–5 m (13–16 ft) vertically along the fault line. Early speculation was that some of the smaller islands south-west of Sumatra, which is on the Burma plate (the southern regions are on the Sunda plate ), might have moved south-west by up to 36 m (120 ft), but more accurate data released more than

4480-674: The minutes preceding a tsunami strike, the sea sometimes recedes temporarily from the coast, which was observed on the eastern earthquake rupture zone such as the coastlines of Aceh, Phuket island, and Khao Lak area in Thailand, Penang island of Malaysia, and the Andaman and Nicobar islands . This rare sight reportedly induced people, especially children, to visit the coast to investigate and collect stranded fish on as much as 2.5 km (1.6 mi) of exposed beach, with fatal results. However, not all tsunamis cause this "disappearing sea" effect. In some cases, there are no warning signs at all:

4560-512: The national stadium, is in Victoria. It is mostly used for football matches. Victoria is served by Seychelles International Airport , completed in 1971. The inner harbour lies immediately east of the town, where tuna fishing and canning is a major industry. One of the largest bridges in Victoria was destroyed by tsunami waves from the 2004 Indian Ocean earthquake . Four of the districts of Seychelles are in Victoria: Victoria

4640-464: The parameters of the source earthquake without having to compensate for the complex ways in which proximity to the coast changes the size and shape of a wave. Before the 2004 quake there were three arguments against a large earthquake occurring in the Sumatra region. After the quake it was considered that earthquake hazard risk would need to be reassessed for regions previously thought to have low risk based on these criteria: The sudden vertical rise of

4720-463: The region of the original epicentre in the hours and days that followed. The magnitude 8.6 2005 Nias–Simeulue earthquake , which originated off the coast of the Sumatran island of Nias , is not considered an aftershock, despite its proximity to the epicentre, and was most likely triggered by stress changes associated with the 2004 event. The earthquake produced its own aftershocks (some registering

4800-413: The region's north and east coast were Pidie Regency , Samalanga , Panteraja , and Lhokseumawe . The high fatality rate in the area was mainly due to lack of preparation of the community towards a tsunami and limited knowledge and education among the population regarding the natural phenomenon. Helicopter surveys revealed entire settlements virtually destroyed, with destruction extending miles inland. Only

4880-470: The sea will suddenly swell without retreating, surprising many people and giving them little time to flee. One of the few coastal areas to evacuate ahead of the tsunami was on the Indonesian island of Simeulue , close to the epicentre. Island folklore recounted an earthquake and tsunami in 1907 , and the islanders fled to inland hills after the initial shaking and before the tsunami struck. These tales and oral folklore from previous generations may have helped

SECTION 60

#1732779991297

4960-502: The seabed around the earthquake zone, which varies in depth between 1,000 and 5,000 m (550 and 2,730 fathoms; 3,300 and 16,400 ft). The survey, conducted using a high-resolution, multi-beam sonar system, revealed that the earthquake had made a considerable impact on the topography of the seabed. 1,500-metre-high (5,000 ft) thrust ridges created by previous geologic activity along the fault had collapsed, generating landslides several kilometres wide. One such landslide consisted of

5040-485: The seabed by several metres during the earthquake displaced massive volumes of water, resulting in a tsunami that struck the coasts of the Indian Ocean. A tsunami that causes damage far away from its source is sometimes called a teletsunami and is much more likely to be produced by the vertical motion of the seabed than by horizontal motion. The tsunami, like all the others, behaved differently in deep water than in shallow water. In deep ocean water, tsunami waves form only

5120-411: The seabed, prompting locals to collect stranded fish and explore the area. Local eyewitnesses described three large waves, with the first wave rising gently to the foundation of the buildings, followed minutes later by a sudden withdrawal of the sea near the port of Ulèë Lheue . This was succeeded by the appearance of two large black-coloured steep waves which then travelled inland into the capital city as

5200-475: The shallow Andaman Sea off its western coast. The tsunami was noticed as far as Struisbaai in South Africa, about 8,500 km (5,300 mi) away, where a 1.5-metre-high (5 ft) tide surged on shore about 16 hours after the earthquake. It took a relatively long time to reach Struisbaai at the southernmost point of Africa, probably because of the broad continental shelf off South Africa and because

5280-422: The shoreline, houses, except for strongly-built reinforced concrete ones with brick walls, which seemed to have been partially damaged by the earthquake before the tsunami attack, were swept away or destroyed by the tsunami. The area toward the sea was wiped clean of nearly every structure, while closer to the river, dense construction in a commercial district showed the effects of severe flooding. The flow depth at

5360-446: The survival of the inhabitants. On Maikhao Beach in north Phuket City , Thailand, a 10-year-old British tourist named Tilly Smith had studied tsunamis in geography at school and recognised the warning signs of the receding ocean and frothing bubbles. She and her parents warned others on the beach, which was evacuated safely. John Chroston , a biology teacher from Scotland, also recognised the signs at Kamala Bay north of Phuket, taking

5440-481: The treaty on behalf of Seychelles. This France -related article is a stub . You can help Misplaced Pages by expanding it . This article relating to law in Seychelles is a stub . You can help Misplaced Pages by expanding it . This article related to a treaty is a stub . You can help Misplaced Pages by expanding it . Victoria, Seychelles Victoria ( French pronunciation: [viktɔʁja] )

5520-797: The tripoint with Madagascar . The treaty came into force immediately upon signature. The full name of the treaty is Agreement between the Government of the French Republic and the Government of the Republic of Seychelles concerning Delimitation of the Maritime Boundary of the Exclusive Economic Zone and the Continental Shelf of France and of Seychelles . Foreign Minister Jérémie Bonnelame signed

5600-431: The tsunami as it was crossing the ocean. These satellites carry radars that measure precisely the height of the water surface; anomalies in the order of 500 mm (20 in) were measured. Measurements from these satellites may prove invaluable for the understanding of the earthquake and tsunami. Unlike data from tide gauges installed on shores, measurements obtained in the middle of the ocean can be used for computing

5680-573: The tsunami would have followed the South African coast from east to west. The tsunami also reached Antarctica, where tidal gauges at Japan's Showa Base recorded oscillations of up to a metre (3 ft 3 in), with disturbances lasting a couple of days. Some of the tsunami's energy escaped into the Pacific Ocean, where it produced small but measurable tsunamis along the western coasts of North and South America, typically around 200 to 400 mm (7.9 to 15.7 in). At Manzanillo , Mexico,

5760-518: The west coast from Moratuwa to Ambalangoda . Sri Lanka tsunami height survey: A regular passenger train operating between Maradana and Matara was derailed and overturned by the tsunami and claimed at least 1,700 lives, the largest single rail disaster death toll in history. Estimates based on the state of the shoreline and a high-water mark on a nearby building place the tsunami 7.5–9 m (25–30 ft) above sea level and 2–3 m (6 ft 7 in – 9 ft 10 in) higher than

5840-405: The world since modern seismography began in 1900. It had the longest fault rupture ever observed, between 1,200 km and 1,300 km (720 mi and 780 mi), and had the longest duration of faulting ever observed, at least ten minutes. It caused the planet to vibrate as much as 10 mm (0.4 in), and also remotely triggered earthquakes as far away as Alaska . Its epicentre

5920-471: Was among the hardest hit by the tsunami. The waves arrived after the sea receded about 500 m (1,600 ft), followed by an advancing small tsunami. The second and third destructive waves arrived later, which exceeded the height of the coconut trees. The inundation distance is about 5 km (3.1 mi). Other towns on Aceh's west coast hit by the disaster included Leupung , Lhokruet , Lamno , Patek, Calang , and Teunom . Affected or destroyed towns on

6000-536: Was approximately 160 km (100 mi) off the western coast of northern Sumatra, in the Indian Ocean just north of Simeulue island at a depth of 30 km (19 mi) below mean sea level (initially reported as 10 km or 6.2 mi). The northern section of the Sunda megathrust ruptured over a length of 1,300 km (810 mi). The earthquake (followed by the tsunami) was felt in Bangladesh , India , Malaysia , Myanmar , Thailand , Sri Lanka and

6080-422: Was between Simeulue and mainland Sumatra. The plight of the affected people and countries prompted a worldwide humanitarian response , with donations totalling more than US$ 14 billion (equivalent to US$ 23 billion in 2023 currency). The 2004 Indian Ocean earthquake was initially documented as having a moment magnitude of 8.8. The United States Geological Survey has its estimate of 9.1. Hiroo Kanamori of

6160-418: Was caused by the 1883 eruption of Krakatoa . Not every earthquake produces large tsunamis: on 28 March 2005, a magnitude 8.7 earthquake hit roughly the same area of the Indian Ocean but did not result in a major tsunami. The first warning sign of a possible tsunami is the earthquake itself. However, tsunamis can strike thousands of kilometres away where the earthquake is felt only weakly or not at all. Also, in

6240-885: Was due to the 2004 Indian Ocean earthquake. This quake, together with the Great Alaskan earthquake (1964) and the Great Chilean earthquake (1960), account for almost half of the total moment. Since 1900, the only earthquakes recorded with a greater magnitude were the 1960 Valdivia earthquake (magnitude 9.5) and the 1964 Alaska earthquake in Prince William Sound (magnitude 9.2). The only other recorded earthquakes of magnitude 9.0 or greater were off Kamchatka , Russia, on 5 November 1952 (magnitude 9.0) and Tōhoku, Japan (magnitude 9.1) in March 2011 . Each of these megathrust earthquakes also spawned tsunamis in

6320-420: Was extreme on the northwestern areas of the city, immediately inland of the aquaculture ponds, and directly facing the Indian Ocean. The tsunami height was reduced from 12 m (39 ft) at Ulee Lheue to 6 m (20 ft) a further 8 km (5.0 mi) to the north-east. The inundation was observed to extend 3–4 km (1.9–2.5 mi) inland throughout the city. Within 2–3 km (1.2–1.9 mi) of

6400-530: Was originally settled in 1778 by French colonists after they claimed the island in 1756. The town was called L'Établissement until 1841 when it was renamed to Victoria by the British, after Queen Victoria . Tourism is an important sector of the economy. The principal exports of Victoria are vanilla , coconuts , coconut oil , fish and guano . The Mont Fleuri campus of the University of Seychelles

#296703