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87-578: The Bayard Dominick expedition was a 1920 scientific expedition to the Pacific islands of Polynesia , with four teams sent to compile archaeological and anthropological surveys of the Marquesas , Tonga , Austral Islands , and Hawaiʻi . The expedition's first year was financed by Bayard Dominick who was a member of the New York Stock Exchange . He gave a gift to Yale University of $ 40,000 and this

174-631: A central lagoon . Important human migrations occurred in the Pacific in prehistoric times. Modern humans first reached the western Pacific in the Paleolithic , at around 60,000 to 70,000 years ago. Originating from a southern coastal human migration out of Africa, they reached East Asia , Mainland Southeast Asia , the Philippines, New Guinea , and then Australia by making the sea crossing of at least 80 kilometres (50 mi) between Sundaland and Sahul . It

261-782: A month after descending four times to the bottom of the Challenger Deep , which is also approximately 6,000 km away from the Tonga Trench. The region between the Tonga trench and the Lau back-arc basin , the Tonga-Kermadec Ridge , moves independently from the Australian and Pacific plates and is subdivided into several small plates, the Tonga , Kermadec , and Niuafo'ou plates. The Tonga plate

348-641: A result is the earth's most active zone of mantle seismicity . Subduction rates decrease southward along the Tonga-Kermadec Arc, from 24 cm/year (9.4 in/year) in the north to 6 cm/year (2.4 in/year) in the south and also become more oblique southward. The high rate in the Tonga Trench is largely due to a reduction in extension in the Lau Basin. Crustal extension in the Miocene Lau-Colville Ridge began at 6 Ma which initiated

435-528: Is 4,280 m (14,040 ft; 2,340 fathoms), putting the total water volume at roughly 710,000,000 km (170,000,000 cu mi). Due to the effects of plate tectonics , the Pacific Ocean is currently shrinking by roughly 2.5 cm (1 in) per year on three sides, roughly averaging 0.52 km (0.20 sq mi) a year. By contrast, the Atlantic Ocean is increasing in size. Along

522-501: Is expected to be completely consumed by the trench within 500,000 years. When the Apollo 13 mission was aborted in 1970 following an explosion in an oxygen tank, it had to bring the entire Lunar Module back to Earth. As the LEM was jettisoned prior to reentry, its radioisotope thermoelectric generator broke up in the atmosphere, and the heat source plunged into an area of the Pacific Ocean that

609-427: Is facing the Tonga Trench. The Tonga Trench-Arc system is an extension-dominated, non-accretionary convergent margin. The Pacific plate is being subducted westward in the trench. The convergence rate has been estimated to 15 cm/year (5.9 in/year) but GPS measurements in the northern trench indicate a convergence rate of 24 cm/year (9.4 in/year) there. This is the fastest plate velocity on Earth,

696-491: Is not known with any certainty what level of maritime technology was used by these groups – the presumption is that they used large bamboo rafts which may have been equipped with some sort of sail. The reduction in favourable winds for a crossing to Sahul after 58,000 B.P. fits with the dating of the settlement of Australia, with no later migrations in the prehistoric period. The seafaring abilities of pre-Austronesian residents of Island South-east Asia are confirmed by

783-693: Is one of three major spreading centres in the northern Lau Basin (together with the Futuna Spreading Centre and Northwest Lau Spreading Centre). The maximum spreading rate in the NELSC is 94 mm/a (3.7 in/year) but spreading decreases to zero at either end of the spreading centre. The total spreading rate between the Tongan and Australian plates, however, is 157 mm/a (6.2 in/year), and additional microplates and/or deformations zones must thus exist. The NELSC probably receives magmatic contributions from

870-670: The Americas , although evidence for this remains inconclusive. The first contact of European navigators with the western edge of the Pacific Ocean was made by the Portuguese expeditions of António de Abreu and Francisco Serrão , via the Lesser Sunda Islands , to the Maluku Islands , in 1512, and with Jorge Álvares 's expedition to southern China in 1513, both ordered by Afonso de Albuquerque from Malacca . The eastern side of

957-424: The Americas , more than 25,000 islands, large and small, rise above the surface of the Pacific Ocean. Multiple islands were the shells of former active volcanoes that have lain dormant for thousands of years. Close to the equator, without vast areas of blue ocean, are a dot of atolls that have over intervals of time been formed by seamounts as a result of tiny coral islands strung in a ring within surroundings of

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1044-620: The Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica ) in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east. At 165,250,000 square kilometers (63,800,000 square miles) in area (as defined with a southern Antarctic border), this largest division of the World Ocean and the hydrosphere covers about 46% of Earth's water surface and about 32% of

1131-510: The Bering Sea in the Arctic to the northern extent of the circumpolar Southern Ocean at 60°S (older definitions extend it to Antarctica 's Ross Sea ), the Pacific reaches its greatest east–west width at about 5°N latitude , where it stretches approximately 19,800 km (12,300 mi) from Indonesia to the coast of Colombia  – halfway around the world, and more than five times

1218-482: The North Fiji Basin , a detached segment of the subducted Australian plate has collided with the subducted Pacific plate which produces many large-scale earthquakes. The subducted Pacific plate is also being deformed in the collision as both slabs settle on the 660 km discontinuity . This slab collision probably occurred 5–4 Ma when the Lau Basin started to open. Oceanic trenches are important sites for

1305-914: The North Pacific Ocean and the South Pacific Ocean (or more loosely the South Seas ). The Pacific Ocean can also be informally divided by the International Date Line into the East Pacific and the West Pacific , which allows it to be further divided into four quadrants, namely the Northeast Pacific off the coasts of North America , the Southeast Pacific off South America , Northwest Pacific off Far Eastern / Pacific Asia , and

1392-583: The Pacific War ; however, by the end of that war, Japan was defeated and the U.S. Pacific Fleet was the virtual master of the ocean. The Japanese-ruled Northern Mariana Islands came under the control of the United States. Since the end of World War II, many former colonies in the Pacific have become independent states . The Pacific separates Asia and Australia from the Americas. It may be further subdivided by

1479-654: The Samoa hotspot . The NELSC has a morphology which is similar to those of slow-spreading ridges with many closely packed ridges and troughs reaches. Where it meets the trench, a ridge-transform-transform boundary is developing between the Tonga Ridge, the Pacific plate, and the Australian plate. North-east of the 60° bend in the Tonga Trench the Pacific seafloor is full of parallel lineations. These have been interpreted as remnants of an extinct, east-to-west-trending spreading centre on

1566-576: The Scripps Institution of Oceanography , the crew of which found the deep in December 1952. As one of the deepest hadal trenches, the sediment of the Horizon Deep harbours a community of roundworms . A 2016 study found that the abundance of individuals in this community is six times greater than it is at a site on the trench edge at approximately 6,250 m (20,510 ft) near the deep and that

1653-708: The Sirena Deep , is also located in the Mariana Trench. The western Pacific has many major marginal seas , including the Philippine Sea , South China Sea , East China Sea , Sea of Japan , Sea of Okhotsk , Bering Sea , Gulf of Alaska , Gulf of California , Mar de Grau , Tasman Sea , and the Coral Sea . In the early 16th century , Spanish explorer Vasco Núñez de Balboa crossed the Isthmus of Panama in 1513 and sighted

1740-693: The Southern Hemisphere . The North Equatorial Current , driven westward along latitude 15°N by the trade winds , turns north near the Philippines to become the warm Japan or Kuroshio Current . Turning eastward at about 45°N , the Kuroshio forks and some water moves northward as the Aleutian Current , while the rest turns southward to rejoin the North Equatorial Current. The Aleutian Current branches as it approaches North America and forms

1827-683: The Southwest Pacific around Oceania . The Pacific Ocean's mean depth is 4,000 meters (13,000 feet). Challenger Deep in the Mariana Trench , located in the northwestern Pacific, is the deepest known point in the world, reaching a depth of 10,928 meters (35,853 feet). The Pacific also contains the deepest point in the Southern Hemisphere , the Horizon Deep in the Tonga Trench , at 10,823 meters (35,509 feet). The third deepest point on Earth,

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1914-662: The Strait of Magellan to the Philippines , the explorer indeed found the ocean peaceful; however, the Pacific is not always peaceful. Many tropical storms batter the islands of the Pacific. The lands around the Pacific Rim are full of volcanoes and often affected by earthquakes . Tsunamis , caused by underwater earthquakes, have devastated many islands and in some cases destroyed entire towns. The Martin Waldseemüller map of 1507

2001-772: The Western Hemisphere . The Southern Pacific Ocean harbors the Southeast Indian Ridge crossing from south of Australia turning into the Pacific-Antarctic Ridge (north of the South Pole ) and merges with another ridge (south of South America) to form the East Pacific Rise which also connects with another ridge (south of North America) which overlooks the Juan de Fuca Ridge . For most of Magellan's voyage from

2088-566: The crab claw sail ) – it is likely that the progressive development of these technologies were related to the later steps of settlement into Near and Remote Oceania. Starting at around 2200 BCE, Austronesians sailed southwards to settle the Philippines . From, probably, the Bismarck Archipelago they crossed the western Pacific to reach the Marianas Islands by 1500 BCE, as well as Palau and Yap by 1000 BCE. They were

2175-855: The Atlantic, the Strait of Magellan was at times patrolled by fleets sent to prevent the entrance of non-Spanish ships. On the western side of the Pacific Ocean the Dutch threatened the Spanish Philippines . The 18th century marked the beginning of major exploration by the Russians in Alaska and the Aleutian Islands , such as the First Kamchatka expedition and the Great Northern Expedition , led by

2262-519: The Atlantic. The andesite line is the most significant regional distinction in the Pacific. A petrologic boundary, it separates the deeper, mafic igneous rock of the Central Pacific Basin from the partially submerged continental areas of felsic igneous rock on its margins. The andesite line follows the western edge of the islands off California and passes south of the Aleutian arc , along

2349-704: The Chilean coast, the South Equatorial Current divides; one branch flows around Cape Horn and the other turns north to form the Peru or Humboldt Current . The climate patterns of the Northern and Southern Hemispheres generally mirror each other. The trade winds in the southern and eastern Pacific are remarkably steady while conditions in the North Pacific are far more varied with, for example, cold winter temperatures on

2436-802: The Danish-born Russian navy officer Vitus Bering . Spain also sent expeditions to the Pacific Northwest , reaching Vancouver Island in southern Canada, and Alaska. The French explored and colonized Polynesia , and the British made three voyages with James Cook to the South Pacific and Australia, Hawaii , and the North American Pacific Northwest . In 1768, Pierre-Antoine Véron , a young astronomer accompanying Louis Antoine de Bougainville on his voyage of exploration, established

2523-623: The Five Deeps expedition, Sirena Deep, itself 5,750 km (3,570 mi) away from Horizon Deep, was visited by Victor Vescovo on the first crewed descent to the bottom of the Sirena Deep on 5 June 2019 (in the Deep-Submergence Vehicle DSV ; Limiting Factor , a Triton 36000/2 model submersible) and measured a depth of 10,823 m (35,509 ft) ±10 m (33 ft) by direct CTD pressure measurements. This descent and direct depth measurement of Sirena Deep occurred

2610-510: The King's or Mangatolu triple junction (MTJ), characterised by deformation and recent and intense volcanism (see for example Home Reef ). The Tofua volcanic arc on the northern Tonga Ridge extends to less than 40 km (25 mi) of the trench's northern end. Just north of the MTJ lies the south–north-trending Northeast Lau Spreading Centre (NELSC) which intercepts the northern end of the Tonga Trench and

2697-537: The Louisville Ridge collision zone, is a 900 km (560 mi)-long extinct spreading ridge midway between two large oceanic plateaux north and south of the Tonga Trench respectively: Manihiki 1,750 km (1,090 mi) to the north and Hikurangi 1,550 km (960 mi) to the south. These plateaux once formed part of the 100 × 10 ^  km (3.5 × 10  cu ft) Ontong Java -Manihiki-Hikurangi large igneous province (LIP). Spreading between

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2784-498: The Moluccas, between 1525 and 1527, Portuguese expeditions encountered the Caroline Islands , the Aru Islands , and Papua New Guinea . In 1542–43 the Portuguese also reached Japan. In 1564, five Spanish ships carrying 379 soldiers crossed the ocean from Mexico led by Miguel López de Legazpi , and colonized the Philippines and Mariana Islands . For the remainder of the 16th century, Spain maintained military and mercantile control, with ships sailing from Mexico and Peru across

2871-449: The Pacific Ring of Fire is the world's foremost belt of explosive volcanism . The Ring of Fire is named after the several hundred active volcanoes that sit above the various subduction zones. The Pacific Ocean is the only ocean which is mostly bounded by subduction zones. Only the central part of the North American coast and the Antarctic and Australian coasts have no nearby subduction zones. Tonga Trench The deepest point of

2958-429: The Pacific Ocean to the Philippines via Guam , and establishing the Spanish East Indies . The Manila galleons operated for two and a half centuries, linking Manila and Acapulco , in one of the longest trade routes in history. Spanish expeditions also arrived at Tuvalu , the Marquesas , the Cook Islands , the Solomon Islands , Vanuatu , the Marshalls and the Admiralty Islands in the South Pacific. Later, in

3045-399: The Pacific Ocean's irregular western margins lie many seas, the largest of which are the Celebes Sea , Coral Sea , East China Sea (East Sea), Philippine Sea , Sea of Japan , South China Sea (South Sea), Sulu Sea , Tasman Sea , and Yellow Sea (West Sea of Korea). The Indonesian Seaway (including the Strait of Malacca and Torres Strait ) joins the Pacific and the Indian Ocean to

3132-402: The Pacific in recorded history. They were part of a Spanish expedition to the Spice Islands that would eventually result in the first world circumnavigation . Magellan called the ocean Pacífico (or "Pacific" meaning, "peaceful") because, after sailing through the stormy seas off Cape Horn , the expedition found calm waters. The ocean was often called the Sea of Magellan in his honor until

3219-413: The Pacific plate, much older than the Tonga Trench. At its southern end ( c.  26°S ) the Tonga Trench is colliding with the Louisville Seamount Chain , a chain of guyots and seamounts on the Pacific plate roughly parallel to the Hawaiian–Emperor seamount chain in the northern pacific. The Louisville collision zone migrates southward at a rate of 18 cm/year (7.1 in/year) because of

3306-540: The Philippines already in 7000 BCE. Additional earlier migrations into Insular Southeast Asia, associated with Austroasiatic-speakers from Mainland Southeast Asia, are estimated to have taken place already in 15000 BCE. At around 1300 to 1200 BCE, a branch of the Austronesian migrations known as the Lapita culture reached the Bismarck Archipelago , the Solomon Islands , Vanuatu , Fiji , and New Caledonia . From there, they settled Tonga and Samoa by 900 to 800 BCE. Some also back-migrated northwards in 200 BCE to settle

3393-434: The Tonga Trench is currently slicing it like a loaf of bread: inside the guyot a north–south-trending horst and graben system is developing parallel to the trench; the western slope of the guyot has reached the 9,000 m deep (30,000 ft) trench and has started to fill it; the summit of the guyot is tilted 1.7° towards the trench and its centre is only 45 km (28 mi) from the trench axis. The Capricorn Seamount

3480-417: The Tonga Trench the bathymetry of these structures is affected by the rotation of the Pacific plate. The Capricorn Seamount is a guyot located on the eastern wall of the northern Tonga Trench (see map above). It is a large guyot, 100 km (62 mi) wide at its base with a small part of its reefal or lagoonal summit reaching 440 m (1,440 ft) below sea level. The bending of the Pacific plate at

3567-417: The Tonga Trench, the Horizon Deep at 23°15′30″S 174°43′36″W  /  23.25833°S 174.726667°W  / -23.25833; -174.726667 , is 10,800 ± 10 m (35,433 ± 33 ft) deep, making it the deepest point in the Southern Hemisphere and the second deepest on Earth after the Challenger Deep in the Mariana Trench . It is named for the research vessel Horizon of

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3654-528: The United States. Significant contributions to oceanographic knowledge were made by the voyages of HMS Beagle in the 1830s, with Charles Darwin aboard; HMS Challenger during the 1870s; the USS Tuscarora (1873–76); and the German Gazelle (1874–76). In Oceania, France obtained a leading position as imperial power after making Tahiti and New Caledonia protectorates in 1842 and 1853, respectively. After navy visits to Easter Island in 1875 and 1887, Chilean navy officer Policarpo Toro negotiated

3741-416: The andesite line and include New Guinea, the islands of New Zealand, and the Philippines. Some of these islands are structurally associated with nearby continents. High islands are of volcanic origin, and many contain active volcanoes. Among these are Bougainville , Hawaii, and the Solomon Islands. The coral reefs of the South Pacific are low-lying structures that have built up on basaltic lava flows under

3828-408: The andesite line. Within the closed loop of the andesite line are most of the deep troughs, submerged volcanic mountains, and oceanic volcanic islands that characterize the Pacific basin. Here basaltic lavas gently flow out of rifts to build huge dome-shaped volcanic mountains whose eroded summits form island arcs, chains, and clusters. Outside the andesite line, volcanism is of the explosive type, and

3915-409: The arctic, icing from October to May can present a hazard for shipping while persistent fog occurs from June to December. A climatological low in the Gulf of Alaska keeps the southern coast wet and mild during the winter months. The Westerlies and associated jet stream within the Mid-Latitudes can be particularly strong, especially in the Southern Hemisphere, due to the temperature difference between

4002-421: The base of a counter-clockwise circulation in the Bering Sea . Its southern arm becomes the chilled slow, south-flowing California Current . The South Equatorial Current , flowing west along the equator, swings southward east of New Guinea , turns east at about 50°S , and joins the main westerly circulation of the South Pacific, which includes the Earth-circling Antarctic Circumpolar Current . As it approaches

4089-408: The diameter of the Moon. Its geographic center is in eastern Kiribati south of Kiritimati , just west from Starbuck Island at 4°58′S 158°45′W  /  4.97°S 158.75°W  / -4.97; -158.75 . The lowest known point on Earth – the Mariana Trench  – lies 10,911 m (35,797  ft ; 5,966 fathoms ) below sea level. Its average depth

4176-402: The difference between temperatures aloft and sea surface temperatures is the greatest; however, each particular basin has its own seasonal patterns. On a worldwide scale, May is the least active month, while September is the most active month. November is the only month in which all the tropical cyclone basins are active. The Pacific hosts the two most active tropical cyclone basins , which are

4263-408: The difference in biomass between these locations is even bigger. Species diversity, on the other hand, is twice as big on the trench slope, probably because of a small number of opportunistic species in the trench. Figures for abundance and biomass are similar for the deeps of the Mariana Trench but considerably lower in the Peru–Chile Trench . The Tonga Trench and the operating area was surveyed by

4350-421: The difference in the oblique angle between the Louisville Ridge relative the direction of convergence. In the eastern Lau Basin spreading centres are propagating southward at roughly the same rate. The collision zone also offsets the Tonga Trench to the north-west relative to the Kermadec Trench by c.  50 km (31 mi) . The subducting Louisville Ridge has caused a significant amount of erosion on

4437-434: The east and the islands of Kiribati in the southeast. Melanesia, to the southwest, includes New Guinea , the world's second largest island after Greenland and by far the largest of the Pacific islands. The other main Melanesian groups from north to south are the Bismarck Archipelago , the Solomon Islands , Santa Cruz , Vanuatu , Fiji and New Caledonia . The largest area, Polynesia , stretching from Hawaii in

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4524-423: The east coast of Russia contrasting with the milder weather off British Columbia during the winter months due to the preferred flow of ocean currents . In the tropical and subtropical Pacific, the El Niño Southern Oscillation (ENSO) affects weather conditions. To determine the phase of ENSO, the most recent three-month sea surface temperature average for the area approximately 3,000 km (1,900 mi) to

4611-403: The eastern edge of the Kamchatka Peninsula , the Kuril Islands , Japan, the Mariana Islands , the Solomon Islands , and New Zealand's North Island . The dissimilarity continues northeastward along the western edge of the Andes Cordillera along South America to Mexico, returning then to the islands off California. Indonesia, the Philippines, Japan, New Guinea, and New Zealand lie outside

4698-410: The eighteenth century. Magellan stopped at one uninhabited Pacific island before stopping at Guam in March 1521. Although Magellan himself died in the Philippines in 1521, Spanish navigator Juan Sebastián Elcano led the remains of the expedition back to Spain across the Indian Ocean and round the Cape of Good Hope , completing the first world circumnavigation in 1522. Sailing around and east of

4785-487: The equator into northern (North Pacific) and southern (South Pacific) portions. It extends from the Antarctic region in the South to the Arctic in the north. The Pacific Ocean encompasses approximately one-third of the Earth's surface, having an area of 165,200,000 km (63,800,000 sq mi) – larger than Earth's entire landmass combined, 150,000,000 km (58,000,000 sq mi). Extending approximately 15,500 km (9,600 mi) from

4872-469: The equator, which can have a salinity as low as 34 parts per thousand, is less salty than that found in the mid-latitudes because of abundant equatorial precipitation throughout the year. The lowest counts of less than 32 parts per thousand are found in the far north as less evaporation of seawater takes place in these frigid areas. The motion of Pacific waters is generally clockwise in the Northern Hemisphere (the North Pacific gyre ) and counter-clockwise in

4959-420: The first completely documented European landing in Australia (1606), in Cape York Peninsula , and Abel Janszoon Tasman circumnavigated and landed on parts of the Australian continental coast and arrived at Tasmania and New Zealand in 1642. In the 16th and 17th centuries, Spain considered the Pacific Ocean a mare clausum  – a sea closed to other naval powers. As the only known entrance from

5046-420: The first humans to reach Remote Oceania , and the first to cross vast distances of open water. They also continued spreading southwards and settling the rest of Maritime Southeast Asia , reaching Indonesia and Malaysia by 1500 BCE, and further west to Madagascar and the Comoros in the Indian Ocean by around 500 CE. More recently, it is suggested that Austronesians expanded already earlier, arriving in

5133-409: The formation of what will become continental crust and for recycling of material back into the mantle . Along the Tonga Trench mantle-derived melts are transferred to the island arc systems, and abyssal oceanic sediments and fragments of oceanic crust are collected. The northern end of the Tonga Trench (at 15°10'S) is probably linked to the Fiji Fracture Zone , trending east–west north of Fiji, but

5220-442: The friction during subduction, others are produced in the Pacific plate due to its bending. The Pacific crust that descends into the trench is old, 100–140 Ma, and relatively cold and it can therefore store a lot of elastic energy. As it reaches deep into the mantle, more than 600 km (370 mi), and encounters barriers, it is being contorted, which produces deep mantle earthquakes. About 500 km (310 mi) beneath

5307-423: The great "Southern Sea" which he named Mar del Sur (in Spanish). Afterwards, the ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favorable winds on reaching the ocean. He called it Mar Pacífico , which in Portuguese means 'peaceful sea'. Top large seas: Across the continents of Asia, Australia and

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5394-439: The incorporation of the island into Chile with native Rapanui in 1888. By occupying Easter Island, Chile joined the imperial nations. By 1900 nearly all Pacific islands were in control of Britain, France, United States, Germany, Japan, and Chile. Although the United States gained control of Guam and the Philippines from Spain in 1898, Japan controlled most of the western Pacific by 1914 and occupied many other islands during

5481-417: The islands in the world. There are about 25,000 islands in the Pacific Ocean. The islands entirely within the Pacific Ocean can be divided into three main groups known as Micronesia , Melanesia and Polynesia . Micronesia, which lies north of the equator and west of the International Date Line , includes the Mariana Islands in the northwest, the Caroline Islands in the center, the Marshall Islands to

5568-519: The islands of eastern Micronesia (including the Carolines , the Marshall Islands , and Kiribati ), mixing with earlier Austronesian migrations in the region. This remained the furthest extent of the Austronesian expansion into Polynesia until around 700 CE when there was another surge of island exploration. They reached the Cook Islands , Tahiti , and the Marquesas by 700 CE; Hawaiʻi by 900 CE; Rapa Nui by 1000 CE; and finally New Zealand by 1200 CE. Austronesians may have also reached as far as

5655-406: The mechanism behind this process is poorly understood. Geochemical evidence suggests that the Louisville chain has been subducting under the Tonga-Kermadec Arc since 4 Ma. Seismic studies have identified a southward, along-arc mantle flow that indicate that Pacific mantle is being replaced by Indo-Australian mantle west of the Tonga Trench. The Osbourn Trough, located at 25.5°S just north of

5742-468: The north to New Zealand in the south, also encompasses Tuvalu , Tokelau , Samoa , Tonga and the Kermadec Islands to the west, the Cook Islands , Society Islands and Austral Islands in the center, and the Marquesas Islands , Tuamotu , Mangareva Islands , and Easter Island to the east. Islands in the Pacific Ocean are of four basic types: continental islands, high islands, coral reefs and uplifted coral platforms. Continental islands lie outside

5829-485: The northern Philippines , but also earlier groups associated with Austroasiatic-speakers , resulting in the modern peoples of Island Southeast Asia and Oceania. A later seaborne migration is the Neolithic Austronesian expansion of the Austronesian peoples . Austronesians originated from the island of Taiwan c.  3000 –1500 BCE. They are associated with distinctive maritime sailing technologies (notably outrigger boats , catamarans , lashed-lug boats, and

5916-433: The northwestern Pacific and the eastern Pacific. Pacific hurricanes form south of Mexico, sometimes striking the western Mexican coast and occasionally the Southwestern United States between June and October, while typhoons forming in the northwestern Pacific moving into southeast and east Asia from May to December. Tropical cyclones also form in the South Pacific basin , where they occasionally impact island nations. In

6003-399: The ocean was encountered by Spanish explorer Vasco Núñez de Balboa in 1513 after his expedition crossed the Isthmus of Panama and reached a new ocean. He named it Mar del Sur ("Sea of the South" or "South Sea" ) because the ocean was to the south of the coast of the isthmus where he first observed the Pacific. In 1520, navigator Ferdinand Magellan and his crew were the first to cross

6090-439: The ocean's surface. One of the most dramatic is the Great Barrier Reef off northeastern Australia with chains of reef patches. A second island type formed of coral is the uplifted coral platform, which is usually slightly larger than the low coral islands. Examples include Banaba (formerly Ocean Island) and Makatea in the Tuamotu group of French Polynesia . The volume of the Pacific Ocean, representing about 50.1 percent of

6177-413: The opening of the Lau Basin - Havre Trough . This extension has propagated southward since and has developed into a spreading centre in the Lau Basin in front of the Tonga Trench. New crust is thus produced in front of the Tonga-Kermadec trenches while old crust is consumed behind it in the Tonga Trench. While most of the large earthquakes occur at the contact zone between both tectonic plates, related to

6264-572: The outer edge of the southern Tonga fore-arc and has probably accelerated subsidence in the Tonga Trench, a process which makes the Tonga Trench the second deepest trench on Earth and considerably deeper than the Kermadec Trench. The oldest and westernmost of the Louisville seamounts, the Osbourn Seamount , is sitting on the edge of the trench and its former flat top is currently tilting towards

6351-517: The planet's total surface area, larger than its entire land area (148,000,000 km (57,000,000 sq mi)). The centers of both the Water Hemisphere and the Western Hemisphere , as well as the oceanic pole of inaccessibility , are in the Pacific Ocean. Ocean circulation (caused by the Coriolis effect ) subdivides it into two largely independent volumes of water that meet at the equator ,

6438-578: The plateaux ceased when Hikurangi collided with the Chatham Rise east of New Zealand which had been estimated to have been at 86 Ma, although may be as recent as 79 Ma. The western end of the Osbourn Trough is bounded by the Tonga Trench and its eastern by the Wishbone–East Manihiki scarp . In between the Osbourn Trough is divided into three segments separated by dextral offsets. Near

6525-569: The quest for Terra Australis ("the [great] Southern Land"), Spanish explorations in the 17th century, such as the expedition led by the Portuguese navigator Pedro Fernandes de Queirós , arrived at the Pitcairn and Vanuatu archipelagos, and sailed the Torres Strait between Australia and New Guinea, named after navigator Luís Vaz de Torres . Dutch explorers, sailing around southern Africa, also engaged in exploration and trade; Willem Janszoon , made

6612-500: The settlement of Buka by 32,000 B.P. and Manus by 25,000 B.P. Journeys of 180 kilometres (110 mi) and 230 kilometres (140 mi) are involved, respectively. The descendants of these migrations today are the Negritos , Melanesians , and Indigenous Australians . Their populations in maritime Southeast Asia , coastal New Guinea , and Island Melanesia later intermarried with the incoming Austronesian settlers from Taiwan and

6699-500: The southeast of Hawaii is computed, and if the region is more than 0.5 °C (0.9 °F) above or below normal for that period, then an El Niño or La Niña is considered in progress. In the tropical western Pacific, the monsoon and the related wet season during the summer months contrast with dry winds in the winter which blow over the ocean from the Asian landmass. Worldwide, tropical cyclone activity peaks in late summer, when

6786-634: The support ship, the Deep Submersible Support Vessel DSSV Pressure Drop , with a Kongsberg SIMRAD EM124 multibeam echosounder system. The gathered data will be donated to the GEBCO Seabed 2030 initiative. The dive was part of the Five Deeps Expedition . The objective of this expedition is to thoroughly map and visit the deepest points of all five of the world's oceans by the end of September 2019. As part of

6873-416: The trench ends in a complex transition from subduction to a strike-slip motion and seismicity patterns indicate a presence of a c.  100 km-broad (62 mi) transition zone rather than a simple transform fault . In or near this zone there is a ridge-ridge-ridge triple junction ( 15°37′S 174°52′W  /  15.617°S 174.867°W  / -15.617; -174.867 ), known as

6960-669: The trench. West of the Osbourn Seamount a broad zone of faulted blocks shallows the trench by 3,000 m (9,800 ft) while the adjacent fore-arc is elevated by c.  300 m (980 ft) and covered by canyons . The Louisville collision zone correlates with a zone of seismic quiescence along the Tonga-Kermadec Trench known as the "Louisville Gap". This gap in seismicity indicates that subducting seamounts inhibit or even prevent seismicity at subduction zones, perhaps by increasing intervals between earthquakes, but

7047-786: The tropics and Antarctica, which records the coldest temperature readings on the planet. In the Southern hemisphere, because of the stormy and cloudy conditions associated with extratropical cyclones riding the jet stream, it is usual to refer to the Westerlies as the Roaring Forties, Furious Fifties and Shrieking Sixties according to the varying degrees of latitude. The ocean was first mapped by Abraham Ortelius ; he called it Maris Pacifici following Ferdinand Magellan 's description of it as "a pacific sea" during his circumnavigation from 1519 to 1522. To Magellan, it seemed much more calm (pacific) than

7134-566: The west, and Drake Passage and the Strait of Magellan link the Pacific with the Atlantic Ocean on the east. To the north, the Bering Strait connects the Pacific with the Arctic Ocean . As the Pacific straddles the 180th meridian , the West Pacific (or western Pacific , near Asia) is in the Eastern Hemisphere , while the East Pacific (or eastern Pacific , near the Americas) is in

7221-525: The width of the Pacific with precision for the first time in history. One of the earliest voyages of scientific exploration was organized by Spain in the Malaspina Expedition of 1789–1794. It sailed vast areas of the Pacific, from Cape Horn to Alaska, Guam and the Philippines, New Zealand, Australia, and the South Pacific. Growing imperialism during the 19th century resulted in the occupation of much of Oceania by European powers, and later Japan and

7308-434: The world's oceanic water, has been estimated at some 714 million cubic kilometers (171 million cubic miles). Surface water temperatures in the Pacific can vary from −1.4 °C (29.5 °F), the freezing point of seawater, in the poleward areas to about 30 °C (86 °F) near the equator. Salinity also varies latitudinally, reaching a maximum of 37 parts per thousand in the southeastern area. The water near

7395-484: Was John F. G. Stokes ( Bishop Museum staff), Robert Thomas Aitken ( Columbia University ) and volunteer assistant Mrs J. F. G. Stokes. Finally the Hawaiian team was Louis R. Sullivan from Brown University and Kenneth P. Emory from Dartmouth , Harvard. Pacific Main five oceans division: Further subdivision: The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions . It extends from

7482-557: Was sent on to the Hawaiian museum. The Tonga team was Edward W. Gifford and William C. McKern both from the University of California and the botanist was Arthur J. Eames from Harvard University . The Marquesas team was Edward S. C. Handy from Harvard and Ralph Linton from the University of Pennsylvania accompanied by the Yale botanist Forest B. H. Brown , and Mrs. Brown and Mrs. Handy as volunteer assistants. The Austral Islands team

7569-572: Was the first to show the Americas separating two distinct oceans. Later, the Diogo Ribeiro map of 1529 was the first to show the Pacific at about its proper size. (Inhabited dependent territories are denoted by the asterisk (*), with names of the corresponding sovereign states in round brackets. Associated states in the Realm of New Zealand are denoted by the hash sign (#).) Territories with no permanent civilian population. The Pacific Ocean has most of

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