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28-619: Researchers believe that the Weber Deep was formed when part of the Earth's crust broke off along a 120 km (75 miles) extension of a fault on the ring of fire , called the Banda Detachment . The break-off was caused by plate tectonics creating a back-arc basin rip in the ocean floor. In parts of Weber Deep there is no oceanic crust on the sea floor due to the rip. The rip is approximately 60,000 km(23,166 miles). Researchers believe Weber Deep

56-418: A solidified division of Earth 's layers that includes the crust and the upper part of the mantle . The lithosphere is broken into tectonic plates whose motion allows heat to escape the interior of Earth into space. The crust lies on top of the mantle, a configuration that is stable because the upper mantle is made of peridotite and is therefore significantly denser than the crust. The boundary between

84-407: A disk of dust and gas orbiting the newly formed Sun. It formed via accretion, where planetesimals and other smaller rocky bodies collided and stuck, gradually growing into a planet. This process generated an enormous amount of heat, which caused early Earth to melt completely. As planetary accretion slowed, Earth began to cool, forming its first crust, called a primary or primordial crust. This crust

112-439: A more felsic composition similar to that of dacite , while the lower crust averages a more mafic composition resembling basalt. The most abundant minerals in Earth 's continental crust are feldspars , which make up about 41% of the crust by weight, followed by quartz at 12%, and pyroxenes at 11%. All the other constituents except water occur only in very small quantities and total less than 1%. Continental crust

140-609: A pattern in English whereby SI units are pronounced with the stress on the first syllable (as in kilogram , kilojoule and kilohertz ) and the pronunciation of the actual base unit does not change irrespective of the prefix (as in centimetre , millimetre , nanometre and so on). It is generally preferred by the British Broadcasting Corporation (BBC), the Canadian Broadcasting Corporation (CBC), and

168-626: A snapshot of the use of the kilometre across Europe: the kilometre was in use in the Netherlands and in Italy, and the myriametre was in use in France. In 1935, the International Committee for Weights and Measures (CIPM) officially abolished the prefix "myria-" and with it the "myriametre", leaving the kilometre as the recognised unit of length for measurements of that magnitude. The symbol km for

196-435: Is 2.835 g/cm , with density increasing with depth from an average of 2.66 g/cm in the uppermost crust to 3.1 g/cm at the base of the crust. In contrast to the continental crust, the oceanic crust is composed predominantly of pillow lava and sheeted dikes with the composition of mid-ocean ridge basalt, with a thin upper layer of sediments and a lower layer of gabbro . Earth formed approximately 4.6 billion years ago from

224-661: Is a unit of length in the International System of Units (SI), equal to one thousand metres ( kilo- being the SI prefix for 1000 ). It is the preferred measurement unit to express distances between geographical places on land in most of the world; notable exceptions are the United States and the United Kingdom where the statute mile is used. There are two common pronunciations for the word. The first pronunciation follows

252-401: Is enriched in incompatible elements compared to the basaltic ocean crust and much enriched compared to the underlying mantle. The most incompatible elements are enriched by a factor of 50 to 100 in the continental crust relative to primitive mantle rock, while oceanic crust is enriched with incompatible elements by a factor of about 10. The estimated average density of the continental crust

280-539: Is even more obvious in countries that use the American spelling of the word metre . This pronunciation is irregular because it makes the kilometre the only SI unit with the stress on the second syllable. After Australia introduced the metric system in 1970, the first pronunciation was declared official by the government's Metric Conversion Board. However, the Australian prime minister at the time, Gough Whitlam , insisted that

308-461: Is preserved in part by depletion of the underlying mantle to form buoyant lithospheric mantle. Crustal movement on continents may result in earthquakes, while movement under the seabed can lead to tidal waves. Kilometre The kilometre ( SI symbol: km ; / ˈ k ɪ l ə m iː t ər / or / k ɪ ˈ l ɒ m ə t ər / ), spelt kilometer in American and Philippine English ,

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336-547: Is the world's largest exposed fault on the ring of fire. The fault along Weber Deep and the Banda Sea is still active. The most extreme event on the fault recorded was in 1629. A Richter magnitude scale 9.2 megathrust earthquake produced a 15-meter (49-foot) tsunami . For nine years after 1629 the area had aftershocks . The closest land to Weber Deep is at the east end of the Banda Sea, surrounded by Watubela archipelago , Timor , Buru , Seram , Ambon and Kur Island . To

364-734: The Canadian Shield , and on other cratonic regions such as those on the Fennoscandian Shield . Some zircon with age as great as 4.3 billion years has been found in the Narryer Gneiss Terrane . Continental crust is a tertiary crust, formed at subduction zones through recycling of subducted secondary (oceanic) crust. The average age of Earth's current continental crust has been estimated to be about 2.0 billion years. Most crustal rocks formed before 2.5 billion years ago are located in cratons . Such an old continental crust and

392-481: The Australian Broadcasting Corporation (ABC). Many other users, particularly in countries where SI (the metric system) is not widely used, use the second pronunciation with stress on the second syllable. The second pronunciation follows the stress pattern used for the names of measuring instruments (such as micrometer , barometer , thermometer , tachometer, and speedometer ). The contrast

420-400: The Weber Deep sea floor deep sea sea cucumbers and aerobic bacteria . 5°26′21″S 131°00′52″E  /  5.439277°S 131.014524°E  / -5.439277; 131.014524 Earth%27s crust Earth's crust is its thick outer shell of rock , referring to less than one percent of the planet's radius and volume . It is the top component of the lithosphere ,

448-417: The continental crust is significantly higher than the surface of the oceanic crust, due to the greater buoyancy of the thicker, less dense continental crust (an example of isostasy ). As a result, the continents form high ground surrounded by deep ocean basins. The continental crust has an average composition similar to that of andesite , though the composition is not uniform, with the upper crust averaging

476-491: The crust and mantle is conventionally placed at the Mohorovičić discontinuity , a boundary defined by a contrast in seismic velocity. The temperature of the crust increases with depth, reaching values typically in the range from about 100 °C (212 °F) to 600 °C (1,112 °F) at the boundary with the underlying mantle. The temperature increases by as much as 30 °C (54 °F) for every kilometer locally in

504-535: The distance from the orbital poles (either North or South) to the Equator , this being a truly internationally based unit. The first name of the kilometre was "Millaire". Although the metre was formally defined in 1799, the myriametre ( 10 000  metres) was preferred to the "kilometre" for everyday use. The term " myriamètre " appeared a number of times in the text of Develey's book Physique d'Emile: ou, Principes de la science de la nature , (published in 1802), while

532-594: The old ocean crust means that the oldest ocean crust on Earth today is only about 200 million years old. In contrast, the bulk of the continental crust is much older. The oldest continental crustal rocks on Earth have ages in the range from about 3.7 to 4.28 billion years and have been found in the Narryer Gneiss Terrane in Western Australia , in the Acasta Gneiss in the Northwest Territories on

560-756: The second pronunciation was the correct one because of the Greek origins of the two parts of the word. By a decree of 8 May 1790, the French National Constituent Assembly ordered the French Academy of Sciences to develop a new measurement system. In August 1793, the French National Convention decreed the metre as the sole length measurement system in the French Republic and it was based on ⁠ 1 / 10 ⁠ millionth of

588-499: The term kilometre only appeared in an appendix. French maps published in 1835 had scales showing myriametres and " lieues de Poste " (Postal leagues of about 4288  metres). The Dutch, on the other hand, adopted the kilometre in 1817 but gave it the local name of the mijl . It was only in 1867 that the term " kilometer " became the only official unit of measure in the Netherlands to represent 1000  metres. Two German textbooks dated 1842 and 1848 respectively give

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616-430: The underlying mantle yields basaltic magmas and new ocean crust forms. This "ridge push" is one of the driving forces of plate tectonics, and it is constantly creating new ocean crust. Consequently, old crust must be destroyed, so opposite a spreading center, there is usually a subduction zone: a trench where an ocean plate is sinking back into the mantle. This constant process of creating a new ocean crust and destroying

644-415: The underlying mantle asthenosphere are less dense than elsewhere on Earth and so are not readily destroyed by subduction. Formation of new continental crust is linked to periods of intense orogeny , which coincide with the formation of the supercontinents such as Rodinia , Pangaea and Gondwana . The crust forms in part by aggregation of island arcs including granite and metamorphic fold belts, and it

672-467: The upper part of the crust. Earth's 40-kilometre (25-mile) deep crust—just one percent of Earth’s mass —contains all known life in the Universe . The crust of Earth is of two distinct types: The average thickness of the crust is about 15 – 20 km (9 – 12 mi). Because both the continental and oceanic crust are less dense than the mantle below, both types of crust "float" on the mantle. The surface of

700-622: The west of the Weber Deep is the Banda Volcanic Arc also called the Inner Banda Arc. The Manuk volcanic island is the closest to the Weber Deep in the Volcanic Arc. The floor of the Weber Deep dates to 3.0 to 0.5 million years old. This young sea floor was created by the eastward expansion (rip) of the Banda Sea. Weber Deep is about 450 km long running north to south. Weber Deep is named after Max Carl Wilhelm Weber (1852–1937), who

728-508: Was found in 1929 by the 204-foot 1928 HMS Willebrord Snelliu (named after Willebrord Snellius ) using an echo sounder on a Dutch oceanographic expedition to the Banda Sea from March 1929 to November 1930. Hilbrand Boschma (1893–1976) was Dutch zoologist on the expedition. In 1951 a more in-depth expedition of Weber Deep and the Banda Sea was done on the Galathea Deep Sea Expedition from 1950 to 1952. The expeditions found on

756-475: Was likely repeatedly destroyed by large impacts, then reformed from the magma ocean left by the impact. None of Earth's primary crust has survived to today; all was destroyed by erosion , impacts, and plate tectonics over the past several billion years. Since then, Earth has been forming a secondary and tertiary crust, which correspond to oceanic and continental crust, respectively. Secondary crust forms at mid-ocean spreading centers , where partial-melting of

784-644: Was the leader of a marine biological expedition, the Siboga expedition , using the 50.6-meter gunboat Siboga of the Dutch East Indies navy. Max Weber was a professor at University of Utrecht and the University of Amsterdam in Amsterdam , his first trip to the Banda Sea was in 1881. The biological expedition departed Amsterdam on the Siboga on December 16, 1898. The expedition also did depth soundings. Weber Deep

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