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103-467: The Bounty Islands ( Māori : Moutere Hauriri ; "Island of angry wind") are a small group of uninhabited granite islets and numerous rocks, with a combined area of circa 50 ha (120 acres) in the South Pacific Ocean. Territorially part of New Zealand , they lie about 670 km (420 mi) east-south-east of New Zealand's South Island , 530 km (330 mi) south-west of

206-420: A completely crystalline rock. Granitic rocks mainly consist of feldspar , quartz , mica , and amphibole minerals , which form an interlocking, somewhat equigranular matrix of feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende ) peppering the lighter color minerals. Occasionally some individual crystals ( phenocrysts ) are larger than the groundmass , in which case

309-563: A depot for marooned sailors on the largest island. Captain Fairchild noted that there was no fresh water available on these islands. The depot had been destroyed by the sea by the time the Stella visited the island in 1887. A new Admiralty chart 1022 was issued for the area in 1888, which took into account survey work undertaken by the Hinemoa . In November 1891 the Hinemoa returned to

412-563: A basaltic magma to a granitic magma, but the quantities produced are small. For example, granitic rock makes up just 4% of the exposures in the South Sandwich Islands . In continental arc settings, granitic rocks are the most common plutonic rocks, and batholiths composed of these rock types extend the entire length of the arc. There are no indication of magma chambers where basaltic magmas differentiate into granites, or of cumulates produced by mafic crystals settling out of

515-472: A belief. The antipodes being an attribute of a spherical Earth , some ancient authors used their perceived absurdity as an argument for a flat Earth . However, knowledge of the spherical Earth was widespread during the Middle Ages, only occasionally disputed—the medieval dispute surrounding the antipodes mainly concerned the question whether people could live on the opposite side of the earth: since

618-693: A breeding site for erect-crested penguins , Salvin's albatrosses and Bounty shags . There are 13 granite islands that make up the Bounty Island group. The whole chain is only 5 km (3.1 mi) across at its longest axis, and comprises three subgroups: the Main Group, the Centre Group, and the East Group. The total area is only 1.35 km (0.52 sq mi). The Main Group is

721-520: A diapir it would expend far too much energy in heating wall rocks, thus cooling and solidifying before reaching higher levels within the crust. Fracture propagation is the mechanism preferred by many geologists as it largely eliminates the major problems of moving a huge mass of magma through cold brittle crust. Magma rises instead in small channels along self-propagating dykes which form along new or pre-existing fracture or fault systems and networks of active shear zones. As these narrow conduits open,

824-517: A few (known as leucogranites ) contain almost no dark minerals. Granite is nearly always massive (lacking any internal structures), hard (falling between 6 and 7 on the Mohs hardness scale) , and tough. These properties have made granite a widespread construction stone throughout human history. The word "granite" comes from the Latin granum , a grain, in reference to the coarse-grained structure of such

927-610: A granite that is derived from partial melting of metasedimentary rocks may have more alkali feldspar, whereas a granite derived from partial melting of metaigneous rocks may be richer in plagioclase. It is on this basis that the modern "alphabet" classification schemes are based. The letter-based Chappell & White classification system was proposed initially to divide granites into I-type (igneous source) granite and S-type (sedimentary sources). Both types are produced by partial melting of crustal rocks, either metaigneous rocks or metasedimentary rocks. I-type granites are characterized by

1030-458: A great circle distance of 17,176 km (10,673 mi; 9,274 nmi). A hypothetically almost perfect antipodal flight would be Tangier Ibn Battouta Airport , Morocco ( IATA : TNG), to Whangarei Aerodrome , New Zealand (IATA: WRE), whose designated locators are 10,800 nautical miles (12,428 mi; 20,002 km) apart, almost the maximum possible distance. However, with only a length of 3,599 ft (1,097 m), Whangarei's runway

1133-565: A high content of sodium and calcium, and by a strontium isotope ratio, Sr/ Sr, of less than 0.708. Sr is produced by radioactive decay of Rb, and since rubidium is concentrated in the crust relative to the mantle, a low ratio suggests origin in the mantle. The elevated sodium and calcium favor crystallization of hornblende rather than biotite. I-type granites are known for their porphyry copper deposits. I-type granites are orogenic (associated with mountain building) and usually metaluminous. S-type granites are sodium-poor and aluminum-rich. As

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1236-824: A much higher proportion of clay with the Cecil soil series a prime example of the consequent Ultisol great soil group. Granite is a natural source of radiation , like most natural stones. Potassium-40 is a radioactive isotope of weak emission, and a constituent of alkali feldspar , which in turn is a common component of granitic rocks, more abundant in alkali feldspar granite and syenites . Some granites contain around 10 to 20 parts per million (ppm) of uranium . By contrast, more mafic rocks, such as tonalite, gabbro and diorite , have 1 to 5 ppm uranium, and limestones and sedimentary rocks usually have equally low amounts. Many large granite plutons are sources for palaeochannel -hosted or roll front uranium ore deposits , where

1339-692: A part of Antarctica. The Australian mainland is the largest landmass with its antipodes entirely in ocean, although some locations of mainland Australia and Tasmania are close to being antipodes of islands (Bermuda, Azores, Puerto Rico) in the North Atlantic Ocean. The largest landmass with antipodes entirely on land is the island of Borneo , whose antipodes are in the Amazon rainforest. Exact or almost exact antipodes: To within 100 km (62 mi), with at least one major city (population of at least 1 million): Taiwan (formerly called Formosa)

1442-536: A peculiar mineralogy and geochemistry, with particularly high silicon and potassium at the expense of calcium and magnesium and a high content of high field strength cations (cations with a small radius and high electrical charge, such as zirconium , niobium , tantalum , and rare earth elements .) They are not orogenic, forming instead over hot spots and continental rifting, and are metaluminous to mildly peralkaline and iron-rich. These granites are produced by partial melting of refractory lithology such as granulites in

1545-430: A person were to go round the world in a circle, he would often, when standing at the antipodes of his former position, speak of the same point as above and below; for, as I was saying just now, to speak of the whole which is in the form of a globe as having one part above and another below is not like a sensible man. The term is taken up by Aristotle ( De caelo 308a.20), Strabo ( Geographica 1.1.13), Plutarch ( On

1648-568: A range of hills, formed by the metamorphic aureole or hornfels . Granite often occurs as relatively small, less than 100 km stock masses ( stocks ) and in batholiths that are often associated with orogenic mountain ranges. Small dikes of granitic composition called aplites are often associated with the margins of granitic intrusions . In some locations, very coarse-grained pegmatite masses occur with granite. Granite forms from silica-rich ( felsic ) magmas. Felsic magmas are thought to form by addition of heat or water vapor to rock of

1751-415: A result, they contain micas such as biotite and muscovite instead of hornblende. Their strontium isotope ratio is typically greater than 0.708, suggesting a crustal origin. They also commonly contain xenoliths of metamorphosed sedimentary rock, and host tin ores. Their magmas are water-rich, and they readily solidify as the water outgasses from the magma at lower pressure, so they less commonly make it to

1854-492: A standard full commercial passenger load. The current world record-holder Airbus A350-900ULR is capable of flying 18,000 kilometres (9,700 nmi; 11,000 mi), or roughly 90% of an average antipodal distance. Singapore Airlines currently holds the world record for the longest scheduled passenger flight , and utilizes this model in their non-stop Singapore to New York-JFK route SQ23/24. In 2019, Qantas completed separate non-stop flights taking 19–20 hours to encompass

1957-549: A translation of the 13th century De Proprietatibus Rerum by Bartholomeus Anglicus , translated by John of Trevisa : Yonde in Ethiopia ben the Antipodes, men that haue theyr fete ayenst our fete. ( In Modern English: Yonder in Ethiopia are the Antipodes, men that have their feet against our feet. ) The modern English singular antipode arose in the 16th or 17th century as a back-formation from antipodes ; antipous or

2060-466: Is grus , which is often made up of coarse-grained fragments of disintegrated granite. Climatic variations also influence the weathering rate of granites. For about two thousand years, the relief engravings on Cleopatra's Needle obelisk had survived the arid conditions of its origin before its transfer to London. Within two hundred years, the red granite has drastically deteriorated in the damp and polluted air there. Soil development on granite reflects

2163-545: Is microgranite . The extrusive igneous rock equivalent of granite is rhyolite . Granitic rock is widely distributed throughout the continental crust . Much of it was intruded during the Precambrian age; it is the most abundant basement rock that underlies the relatively thin sedimentary veneer of the continents. Outcrops of granite tend to form tors , domes or bornhardts , and rounded massifs . Granites sometimes occur in circular depressions surrounded by

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2266-517: Is 3–6·10 Pa·s. The melting temperature of dry granite at ambient pressure is 1215–1260 °C (2219–2300 °F); it is strongly reduced in the presence of water, down to 650 °C at a few hundred megapascals of pressure. Granite has poor primary permeability overall, but strong secondary permeability through cracks and fractures if they are present. A worldwide average of the chemical composition of granite, by weight percent, based on 2485 analyses: The medium-grained equivalent of granite

2369-502: Is a distance of 40,008 kilometres (24,860 mi). Any other closed great circle route starting on the equator and traveling at an angle between 0° (an equatorial route) and 90° (a polar route) would be between 40,075 and 40,008 kilometres (24,901 and 24,860 mi). In all of these cases, after half of the world has been traversed, every subsequent point will be antipodal to one already visited. There are currently no commercial aircraft capable of traveling non-stop between antipodes with

2472-410: Is an excess of aluminum beyond what can be taken up in feldspars (Al 2 O 3 > CaO + K 2 O + Na 2 O) are described as peraluminous , and they contain aluminum-rich minerals such as muscovite . The average density of granite is between 2.65 and 2.75 g/cm (165 and 172 lb/cu ft), its compressive strength usually lies above 200 MPa (29,000 psi), and its viscosity near STP

2575-532: Is antipodal to other land, representing approximately 4.4% of Earth's surface. Another source estimates that about 3% of Earth's surface is antipodal land. The largest antipodal land masses are the Malay Archipelago , antipodal to the Amazon basin and adjoining Andean ranges; east China and Mongolia , and small sections of southeast Russia , antipodal to Argentina and Chile ; and Greenland and

2678-637: Is believed to have a mass of around 81 tonnes. It was the tallest temple in south India. Imperial Roman granite was quarried mainly in Egypt, and also in Turkey, and on the islands of Elba and Giglio . Granite became "an integral part of the Roman language of monumental architecture". The quarrying ceased around the third century AD. Beginning in Late Antiquity the granite was reused, which since at least

2781-434: Is called a binary or two-mica granite. Two-mica granites are typically high in potassium and low in plagioclase, and are usually S-type granites or A-type granites, as described below . Another aspect of granite classification is the ratios of metals that potentially form feldspars. Most granites have a composition such that almost all their aluminum and alkali metals (sodium and potassium) are combined as feldspar. This

2884-575: Is distant from it by 180° of longitude and as many degrees to the north of the Equator as the original is to the south (or vice versa); in other words, the latitudes are numerically equal, but one is north and the other south. The maps shown here are based on this relationship; they show a Lambert azimuthal equal-area projection of the Earth, in yellow, overlaid on which is another map, in blue, shifted horizontally by 180° of longitude and inverted about

2987-433: Is limited by the amount of thermal energy available, which must be replenished by crystallization of higher-melting minerals in the magma. Thus, the magma is melting crustal rock at its roof while simultaneously crystallizing at its base. This results in steady contamination with crustal material as the magma rises. This may not be evident in the major and minor element chemistry, since the minerals most likely to crystallize at

3090-534: Is partly antipodal to the province of Formosa in Argentina . Capital cities within 200 km (120 mi) of each other's antipodes: Other major cities or capitals close to being antipodes: Gibraltar is approximately antipodal to Te Ārai about 85 km (53 mi) north of Auckland , New Zealand . This illustrates the old yet correct saying that the sun never sets on the British Empire ;

3193-404: Is permeated by sheets and channels of light granitic rock (the leucosome ). The leucosome is interpreted as partial melt of a parent rock that has begun to separate from the remaining solid residue (the melanosome). If enough partial melt is produced, it will separate from the source rock, become more highly evolved through fractional crystallization during its ascent toward the surface, and become

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3296-480: Is possible by walking in a circle around one of the poles—but such trips are shorter than a minimum circumnavigation. On the other hand, the greatest straight line distance that could in theory be covered is a trip exactly on the Equator, a distance of 40,075 kilometres (24,901 mi). The Earth's equatorial bulge makes this slightly longer than a north–south trip around the world along a set of meridian lines, which

3399-454: Is relieved when overlying material is removed by erosion or other processes. Chemical weathering of granite occurs when dilute carbonic acid , and other acids present in rain and soil waters, alter feldspar in a process called hydrolysis . As demonstrated in the following reaction, this causes potassium feldspar to form kaolinite , with potassium ions, bicarbonate, and silica in solution as byproducts. An end product of granite weathering

3502-411: Is some concern that some granite sold as countertops or building material may be hazardous to health. Dan Steck of St. Johns University has stated that approximately 5% of all granite is of concern, with the caveat that only a tiny percentage of the tens of thousands of granite slab types have been tested. Resources from national geological survey organizations are accessible online to assist in assessing

3605-479: Is that magma will rise through the crust as a single mass through buoyancy . As it rises, it heats the wall rocks , causing them to behave as a power-law fluid and thus flow around the intrusion allowing it to pass without major heat loss. This is entirely feasible in the warm, ductile lower crust where rocks are easily deformed, but runs into problems in the upper crust which is far colder and more brittle. Rocks there do not deform so easily: for magma to rise as

3708-410: Is the case when K 2 O + Na 2 O + CaO > Al 2 O 3 > K 2 O + Na 2 O. Such granites are described as normal or metaluminous . Granites in which there is not enough aluminum to combine with all the alkali oxides as feldspar (Al 2 O 3 < K 2 O + Na 2 O) are described as peralkaline , and they contain unusual sodium amphiboles such as riebeckite . Granites in which there

3811-583: Is the point on Earth's surface diametrically opposite to it. A pair of points antipodal ( / æ n ˈ t ɪ p ə d əl / ) to each other are situated such that a straight line connecting the two would pass through Earth's center. Antipodal points are as far away from each other as possible. The North and South Poles are antipodes of each other. In the Northern Hemisphere , "the Antipodes" may refer to Australia and New Zealand , and Antipodeans to their inhabitants. Geographically,

3914-775: Is too short to accommodate any current (as of 2015 ) commercial jet airliner, especially one with the required range. Traveling between them would currently need at least two plane changes. Other near-antipodal major city pairs include: The ambiguous airport designation HLA could refer to either Lanseria International Airport ( IATA : HLA , ICAO : FALA , 25°56′S 027°55′E) in South Africa or Huslia Airport ( IATA : HSL , ICAO : PAHL , FAA LID : HLA, 65°42′N 156°21′W) in Alaska. While these airports are not quite antipodal (only 15,581 km (9,682 mi; 8,413 nmi) apart), they are notable considering that they share

4017-459: Is typically orthoclase or microcline and is often perthitic . The plagioclase is typically sodium-rich oligoclase . Phenocrysts are usually alkali feldspar. Granitic rocks are classified according to the QAPF diagram for coarse grained plutonic rocks and are named according to the percentage of quartz , alkali feldspar ( orthoclase , sanidine , or microcline ) and plagioclase feldspar on

4120-428: Is uncommon, is classified simply as quartz-rich granitoid or, if composed almost entirely of quartz, as quartzolite . True granites are further classified by the percentage of their total feldspar that is alkali feldspar. Granites whose feldspar is 65% to 90% alkali feldspar are syenogranites , while the feldspar in monzogranite is 35% to 65% alkali feldspar. A granite containing both muscovite and biotite micas

4223-717: The Airbus A350 , the ACJ350 , which entered into service in 2020, has a range of 20,550 km (12,770 miles), enabling it to operate between any two available antipodes. As of September 2021, there are three ACJ350s now in service globally. The owner of the first ACJ350, the German Government, has already taken it on a close to antipodal flight with a flight from Cologne, Germany to Canberra, Australia in November 2020. The upcoming Boeing business jet variant,

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4326-458: The BBJ 777-8 , will also have an antipodal reach with its published range of 21,570 km (13,403 miles). Both aforementioned variants from Airbus and Boeing are the first aircraft designed to handle flights exceeding the Earth's average antipodal distance of 20,000 km (12,420 miles). Among flights with fuel stop and crew-change stop but still same flight number, Air New Zealand previously had

4429-466: The COVID-19 pandemic . In March 2021, a Comlux 787-8 , registered P4-787, flew a non-scheduled (chartered), non-stop flight from Seoul Incheon to Buenos Aires , which are nearly antipodal points. This set a new record for the longest commercial non-stop flight with paying passengers, covering 19,483 kilometres (10,520 nmi; 12,106 mi) in 20 hours 19 minutes. The business jet variant of

4532-764: The Canadian Arctic Archipelago , antipodal to East Antarctica . There is a general paucity of antipodal land because the Southern Hemisphere has comparatively less land than the Northern Hemisphere and, of that, the antipodes of Australia are in the North Atlantic Ocean , while the antipodes of southern Africa are in the North Pacific Ocean . Since the antipode of any place on the Earth is

4635-614: The Chatham Islands , and 215 km (134 mi) north of the Antipodes Islands . The group is a World Heritage Site . The islands are listed with the New Zealand Outlying Islands . The islands are an immediate part of New Zealand, but not part of any region or district . Rather, they are listed as an Area Outside Territorial Authority , similar to all other outlying islands except for

4738-608: The Greek: ἀντίποδες (antípodes), plural of ἀντίπους (antipous), "with feet opposite (ours)", from ἀντί (antí, “opposite”) + πούς ( poús , “foot”). The Greek word is attested in Plato 's dialogue Timaeus , already referring to a spherical Earth, explaining the relativity of the terms "above" and "below": For if there were any solid body in equipoise at the centre of the universe, there would be nothing to draw it to this extreme rather than to that, for they are all perfectly similar; and if

4841-769: The Solander Islands / Hautere . Captain William Bligh discovered the Bounty Islands en route from Spithead to Tahiti in 1788, and named them after his ship HMS Bounty , just months before the famous mutiny . The location of the islands were only roughly marked on charts. In early 1866 Commander W. H. Norman of HMVS Victoria (1855) was tasked with determining more accurately their position. He reported them as being latitude 47°50' South and longitude 179°00' East. Captain George Palmer, during

4944-679: The antipodes of Bouillé-Ménard , in France ( Pays de la Loire ). The following table includes named islands according to Land Information New Zealand . Granite Granite is typical of a larger family of granitic rocks , or granitoids , that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification ), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though

5047-425: The geographic coordinates ( latitude and longitude ) of a point on the Earth's surface are ( φ , θ ), then the coordinates of the antipodal point are (− φ , θ ± 180°). This relation holds true whether the Earth is approximated as a perfect sphere or as a reference ellipsoid . In terms of the usual way these geographic coordinates are given, this transformation can be expressed symbolically as that is, for

5150-553: The 15th century and "St. Augustine doubts" was a response to Columbus's proposal to sail westwards to the Indies. The author of the Norwegian book Konungs Skuggsjá , from around 1250, discusses the existence of antipodes. He notes that (if they exist) they will see the sun in the north in the middle of the day and that they will have seasons opposite those of the Northern Hemisphere. Herodotus recorded that Pharaoh Necho II of

5253-507: The 16,013 km (9950 miles) from New York and 17,016 km (10,573 miles) from London, both to Sydney, Australia with a limit of 49 passengers on the Boeing 787 Dreamliner and who underwent medical tests on the flight. The London-Sydney direct routes are said to be the world's most profitable ultra-long haul flights annually. Their plans for the same pair of experiments were quickly put on hold due to global travel restrictions throughout

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5356-530: The 26th Dynasty (610–595 BC) commissioned an expedition of Phoenicians which in three years sailed from the Red Sea around Africa back to the mouth of the Nile, and that " as they sailed on a westerly course round the southern end of Libya (Africa), they had the sun on their right "— to northward of them, proving that they had been in the Southern Hemisphere. The earliest surviving account by a European who had visited

5459-571: The A-Q-P half of the diagram. True granite (according to modern petrologic convention) contains between 20% and 60% quartz by volume, with 35% to 90% of the total feldspar consisting of alkali feldspar . Granitic rocks poorer in quartz are classified as syenites or monzonites , while granitic rocks dominated by plagioclase are classified as granodiorites or tonalites . Granitic rocks with over 90% alkali feldspar are classified as alkali feldspar granites . Granitic rock with more than 60% quartz, which

5562-560: The Antipodes by the diplomatist Peter Martyr who, in a letter he wrote from Barcelona dated 14 May 1493, said: "A few days since, a certain Christopher Columbus, a Ligurian, returned from the Western Antipodes". Perhaps influenced by this, Fernão Vaz Dourado in his Atlas of 1571 inscribed over the map of Mexico and adjacent parts of America, Tera Antipodum regis Castelle inventa a Xforo Columbo Januensi (Land of

5665-607: The Antipodes, discovered for the King of Castile by Christopher Columbus of Genoa). In spite of having been discovered relatively late by European explorers, Australia was inhabited very early in human history; the ancestors of the Indigenous Australians reached it at least 50,000 years ago. To make the longest distance trip around the planet, a traveler would have to pass through a set of antipodal points. All meridians can be crossed in one hemisphere—indeed, this

5768-442: The Equator with respect to latitude. Noon at one place is midnight at the other (ignoring daylight saving time and irregularly shaped time zones ) and, with the exception of the tropics , the longest day at one point corresponds to the shortest day at the other, and midwinter at one point coincides with midsummer at the other. Sunrise and sunset do not quite oppose each other at antipodes due to refraction of sunlight. If

5871-615: The European Union safety standards (section 4.1.1.1 of the National Health and Engineering study) and radon emission levels well below the average outdoor radon concentrations in the US. Granite and related marble industries are considered one of the oldest industries in the world, existing as far back as Ancient Egypt . Major modern exporters of granite include China, India, Italy, Brazil, Canada, Germany, Sweden, Spain and

5974-547: The Latinate antipus would have been closer to the original singular. Most dictionaries suggest a pronunciation of / ˈ æ n t ɪ ˌ p oʊ d / for this form. Pomponius Mela , the first Roman geographer, asserted that the earth had two habitable zones, a North and South one, but that it would be impossible to get into contact with each other because of the unbearable heat at the Equator ( De orbis situ 1.4). Third-century AD Christian philospher Augustine of Hippo

6077-605: The Malice of Herodotus 37) and Diogenes Laërtius ( Lives and Opinions of Eminent Philosophers book 3), and was adopted into Latin as antipodes . The Latin word changed its sense from the original "under the feet, opposite side" to "those with the feet opposite", i.e. a bahuvrihi referring to hypothetical people living on the opposite side of the Earth. Medieval illustrations imagine them in some way "inverted", with their feet growing out of their heads, pointing upward. In this sense, Antipodes first entered English in 1398 in

6180-569: The Southern Hemisphere is that of Marco Polo (who, on his way home in 1292, sailed south of the Malay Peninsula ). He noted that it was impossible to see the star Polaris from there. The idea of dry land in the southern climes, the Terra Australis , was introduced by Ptolemy and appears on European maps as an imaginary continent from the 15th century. Antipodes was what Giovanni Contarini , on his world map of 1506 called

6283-511: The United States. The Red Pyramid of Egypt ( c.  2590 BC ), named for the light crimson hue of its exposed limestone surfaces, is the third largest of Egyptian pyramids . Pyramid of Menkaure , likely dating 2510 BC, was constructed of limestone and granite blocks. The Great Pyramid of Giza (c. 2580 BC ) contains a huge granite sarcophagus fashioned of "Red Aswan Granite". The mostly ruined Black Pyramid dating from

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6386-693: The antipodes of the British Isles are in the Pacific Ocean , south of New Zealand. This gave rise to the name of the Antipodes Islands of New Zealand, which are close to the antipode of London . With the exception of a part of the Perth metropolitan area near Baldivis and Rockingham that is antipodal to Bermuda , the antipodes of Australia are in the North Atlantic Ocean , while parts of Spain , Portugal , France and Morocco are antipodal to New Zealand. Approximately 15% of land territory

6489-419: The base of the chamber are the same ones that would crystallize anyway, but crustal assimilation is detectable in isotope ratios. Heat loss to the country rock means that ascent by assimilation is limited to distance similar to the height of the magma chamber. Physical weathering occurs on a large scale in the form of exfoliation joints , which are the result of granite's expanding and fracturing as pressure

6592-418: The big difference in rheology between mafic and felsic magmas makes this process problematic in nature. Granitization is an old, and largely discounted, hypothesis that granite is formed in place through extreme metasomatism . The idea behind granitization was that fluids would supposedly bring in elements such as potassium, and remove others, such as calcium, to transform a metamorphic rock into granite. This

6695-509: The chain's northernmost point; the westernmost point is the western tip of Penguin Island. The Centre Group is located some 1.5 to 2 kilometres to the southeast of the Main Group, and contains three main islands, arrayed in a north–south line. A smaller islet lies immediately to the west. The northernmost of the Centre Group, Funnel Island, contains the chain's highest point, at 73 m (240 ft) above sea level. A further 1.5 kilometres to

6798-404: The division between S-type (produced by underplating) and I-type (produced by injection and differentiation) granites, discussed below. The composition and origin of any magma that differentiates into granite leave certain petrological evidence as to what the granite's parental rock was. The final texture and composition of a granite are generally distinctive as to its parental rock. For instance,

6901-413: The early 16th century became known as spolia . Through the process of case-hardening , granite becomes harder with age. The technology required to make tempered metal chisels was largely forgotten during the Middle Ages. As a result, Medieval stoneworkers were forced to use saws or emery to shorten ancient columns or hack them into discs. Giorgio Vasari noted in the 16th century that granite in quarries

7004-682: The earth's land has an antipode on land. Rough calculation shows that, of the 29% of the earth that is covered by land, if 15% of that has antipodes on land, then about 4% (0.15 × 29% = 4.35%) of the earth's surface has antipodes that are both land surfaces. Spilhaus estimates this at about 3%. The two largest human-inhabited antipodal areas are located in East Asia (mainly eastern China) and South America (mainly Argentina and Chile). The two largest monolithic antipodal land areas are most of Chile and Argentina along with eastern and central China and Mongolia, and most of Greenland along with

7107-417: The east is the East Group, which is also arrayed roughly in a north–south line. The largest island in this group, Molly Cap, is the group's southernmost island, and contains the chain's second-highest point, 70 m (230 ft) above sea level. This group contains two large islets and one small islet, along with several reefs and stacks, one of which is the easternmost point in the chain. The islands are at

7210-579: The first magma to enter solidifies and provides a form of insulation for later magma. These mechanisms can operate in tandem. For example, diapirs may continue to rise through the brittle upper crust through stoping , where the granite cracks the roof rocks, removing blocks of the overlying crust which then sink to the bottom of the diapir while the magma rises to take their place. This can occur as piecemeal stopping (stoping of small blocks of chamber roof), as cauldron subsidence (collapse of large blocks of chamber roof), or as roof foundering (complete collapse of

7313-713: The grotto is a highly regarded piece of Buddhist art , and along with the temple complex to which it belongs, Seokguram was added to the UNESCO World Heritage List in 1995. Rajaraja Chola I of the Chola Dynasty in South India built the world's first temple entirely of granite in the 11th century AD in Tanjore , India . The Brihadeeswarar Temple dedicated to Lord Shiva was built in 1010. The massive Gopuram (ornate, upper section of shrine)

7416-515: The islands and built a fresh provisions storage. Ecologically, the islands are part of the Antipodes Subantarctic Islands tundra ecoregion . Plants include Cook's scurvy grass . The group is home to an endemic spider Pacificana cockayni , endemic insects, and large numbers of seabirds . The Bounty group has been identified as an Important Bird Area (IBA) by BirdLife International because of its significance as

7519-572: The land later named America by Martin Waldseemüller . When the land discovered by Pedro Alvarez Cabral in April 1500, Brazil , was formally named Santa Cruz by the assembled Portuguese court on 20 May 1503, it was also referred to in the official record of the proceedings as the “Land of the Antipodes”: terra Antipodum . The land reached by Columbus in 1492 was identified as that of

7622-401: The largest of the three groups, and is located in the northwest of the chain. It includes the group's largest island, Depot Island, which is around 700 metres in length and 400 metres across at its widest point. Proclamation and Tunnel Islands are separated from Depot Island by only a narrow cleft, and are joined to it at low tide. A small islet off the north coast of this group's Spider Island is

7725-650: The latitude (the north–south coordinate) the magnitude of the angle remains the same but N is changed to S and vice versa, and for the longitude (the East/West coordinate) the angle is replaced by its supplementary angle while E is exchanged for W. For example, the antipode of the point in China at 37° N 119° E (a few hundred kilometres from Beijing ) is the point in Argentina at 37° S 61° W (a few hundred kilometres from Buenos Aires ). The word antipodes comes from

7828-474: The lower crust , rather than by decompression of mantle rock, as is the case with basaltic magmas. It has also been suggested that some granites found at convergent boundaries between tectonic plates , where oceanic crust subducts below continental crust, were formed from sediments subducted with the oceanic plate. The melted sediments would have produced magma intermediate in its silica content, which became further enriched in silica as it rose through

7931-729: The lower continental crust at high thermal gradients. This leads to significant extraction of hydrous felsic melts from granulite-facies resitites. A-type granites occur in the Koettlitz Glacier Alkaline Province in the Royal Society Range, Antarctica. The rhyolites of the Yellowstone Caldera are examples of volcanic equivalents of A-type granite. M-type granite was later proposed to cover those granites that were clearly sourced from crystallized mafic magmas, generally sourced from

8034-435: The magma is inevitable once enough magma has accumulated. However, the question of precisely how such large quantities of magma are able to shove aside country rock to make room for themselves (the room problem ) is still a matter of research. Two main mechanisms are thought to be important: Of these two mechanisms, Stokes diapirism has been favoured for many years in the absence of a reasonable alternative. The basic idea

8137-426: The magma. Other processes must produce these great volumes of felsic magma. One such process is injection of basaltic magma into the lower crust, followed by differentiation, which leaves any cumulates in the mantle. Another is heating of the lower crust by underplating basaltic magma, which produces felsic magma directly from crustal rock. The two processes produce different kinds of granites, which may be reflected in

8240-408: The magmatic parent of granitic rock. The residue of the source rock becomes a granulite . The partial melting of solid rocks requires high temperatures and the addition of water or other volatiles which lower the solidus temperature (temperature at which partial melting commences) of these rocks. It was long debated whether crustal thickening in orogens (mountain belts along convergent boundaries )

8343-405: The mantle. Although the fractional crystallisation of basaltic melts can yield small amounts of granites, which are sometimes found in island arcs, such granites must occur together with large amounts of basaltic rocks. H-type granites were suggested for hybrid granites, which were hypothesized to form by mixing between mafic and felsic from different sources, such as M-type and S-type. However,

8446-516: The opposite side of the Earth), as well as to a geographical place: Apart from these three parts of the world, there exists a fourth part beyond the interior Ocean; it is in the south and is unknown to us because of the burning heat of the Sun; within its borders the fabled Antipodeans are reputed to dwell. In using the form antipodas rather than the more usual Latin antipodes Isidore simply transcribed

8549-506: The original Greek αντίποδας, the singular case of the name: the plural case is αντίποδες (antipodes), used in converting the name into Latin. These people came to play a role in medieval discussions about the shape of the Earth . In 748, in reply to a letter from Boniface , Pope Zachary declared the belief "that beneath the earth there was another world and other men, another sun and moon" to be heretical. In his letter, Boniface had apparently maintained that Vergilius of Salzburg held such

8652-441: The overlying crust. Early fractional crystallisation serves to reduce a melt in magnesium and chromium, and enrich the melt in iron, sodium, potassium, aluminum, and silicon. Further fractionation reduces the content of iron, calcium, and titanium. This is reflected in the high content of alkali feldspar and quartz in granite. The presence of granitic rock in island arcs shows that fractional crystallization alone can convert

8755-465: The place that is diametrically opposite of it, a line drawn from one to the other will pass through the centre of Earth and form a true diameter . For example, the antipodes of New Zealand's lower North Island lie in Spain. Most of the Earth's land surfaces have ocean at their antipodes; this is a natural consequence of most of the Earth's surface being covered in water. The antipode of any place on Earth

8858-736: The reign of Amenemhat III once had a polished granite pyramidion or capstone, which is now on display in the main hall of the Egyptian Museum in Cairo (see Dahshur ). Other uses in Ancient Egypt include columns , door lintels , sills , jambs , and wall and floor veneer. How the Egyptians worked the solid granite is still a matter of debate. Tool marks described by the Egyptologist Anna Serotta indicate

8961-508: The risk factors in granite country and design rules relating, in particular, to preventing accumulation of radon gas in enclosed basements and dwellings. A study of granite countertops was done (initiated and paid for by the Marble Institute of America) in November 2008 by National Health and Engineering Inc. of USA. In this test, all of the 39 full-size granite slabs that were measured for the study showed radiation levels well below

9064-418: The rock's high quartz content and dearth of available bases, with the base-poor status predisposing the soil to acidification and podzolization in cool humid climates as the weather-resistant quartz yields much sand. Feldspars also weather slowly in cool climes, allowing sand to dominate the fine-earth fraction. In warm humid regions, the weathering of feldspar as described above is accelerated so as to allow

9167-414: The rocks often bear a close resemblance. Under these conditions, granitic melts can be produced in place through the partial melting of metamorphic rocks by extracting melt-mobile elements such as potassium and silicon into the melts but leaving others such as calcium and iron in granulite residues. This may be the origin of migmatites . A migmatite consists of dark, refractory rock (the melanosome ) that

9270-492: The roof of a shallow magma chamber accompanied by a caldera eruption.) There is evidence for cauldron subsidence at the Mt. Ascutney intrusion in eastern Vermont. Evidence for piecemeal stoping is found in intrusions that are rimmed with igneous breccia containing fragments of country rock. Assimilation is another mechanism of ascent, where the granite melts its way up into the crust and removes overlying material in this way. This

9373-401: The same designation. Automated systems that select the wrong airport from a database could lead to navigation errors or large outliers in data analysis. Around 71% of the Earth's surface is covered by oceans , and seven-eighths of the Earth's land (when excluding Antarctica) is confined to the land hemisphere , so the majority of locations on land do not have land-based antipodes. About 15% of

9476-638: The search for the Matoaka , placed the islands at 47°46'24" South 178°56'45" East. Palmer also annexed the islands for New Zealand. During the 19th century the area was a popular hunting-ground for sealers . The islands were also searched from time to time for missing ships and crews, including those from the General Grant and the Matoaka . The Hinemoa visited the islands in March 1886 and erected

9579-608: The sun still does not set on the Commonwealth of Nations . The northern part of New Caledonia , an overseas territory of France, is antipodal to some thinly populated desert in Mauritania , a part of the former French West Africa . Portions of Suriname , a former Dutch colony, are antipodal to Sulawesi , an Indonesian island spelled Celebes when it was part of the Netherlands East Indies . Luzon ,

9682-435: The surface than magmas of I-type granites, which are thus more common as volcanic rock (rhyolite). They are also orogenic but range from metaluminous to strongly peraluminous. Although both I- and S-type granites are orogenic, I-type granites are more common close to the convergent boundary than S-type. This is attributed to thicker crust further from the boundary, which results in more crustal melting. A-type granites show

9785-440: The texture is known as porphyritic . A granitic rock with a porphyritic texture is known as a granite porphyry . Granitoid is a general, descriptive field term for lighter-colored, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids. Granites can be predominantly white, pink, or gray in color, depending on their mineralogy . The alkali feldspar in granites

9888-494: The torrid clime was considered impassable, it would have been impossible to evangelize them. This posed the problem that Christ told the apostles to evangelize all mankind; with regard to the unreachable antipodes, this would have been impossible. Christ would either have appeared a second time, in the antipodes, or left the damned irredeemable. Such an argument was forwarded by the Spanish theologian Alonso Tostado as late as

9991-502: The uranium washes into the sediments from the granite uplands and associated, often highly radioactive pegmatites. Cellars and basements built into soils over granite can become a trap for radon gas, which is formed by the decay of uranium. Radon gas poses significant health concerns and is the number two cause of lung cancer in the US behind smoking. Thorium occurs in all granites. Conway granite has been noted for its relatively high thorium concentration of 56±6 ppm. There

10094-617: The use of flint tools on finer work with harder stones, e.g. when producing the hieroglyphic inscriptions. Patrick Hunt has postulated that the Egyptians used emery , which has greater hardness. The Seokguram Grotto in Korea is a Buddhist shrine and part of the Bulguksa temple complex. Completed in 774 AD, it is an artificial grotto constructed entirely of granite. The main Buddha of

10197-528: The world's longest active plane route—the Auckland – Los Angeles – London marathon, at 19,240 km (11,960 mi) over Los Angeles (directly 18,360 km or 11,410 mi)—until the airline cancelled this route late in 2019. The current record holder for such a flight is co-owned by Qantas and British Airways in their operating of the Kangaroo Route 's Sydney—Singapore—London flights covering

10300-437: Was "far softer and easier to work than after it has lain exposed" while ancient columns, because of their "hardness and solidity have nothing to fear from fire or sword, and time itself, that drives everything to ruin, not only has not destroyed them but has not even altered their colour." Antipodes In geography , the antipode ( / ˈ æ n t ɪ ˌ p oʊ d , æ n ˈ t ɪ p ə d i / ) of any spot on Earth

10403-511: Was skeptical of the notion. Augustine asserted that "it is too absurd to say that some men might have set sail from this side and, traversing the immense expanse of ocean, have propagated there a race of human beings descended from that one first man." In the Early Middle Ages , Isidore of Seville 's widely read encyclopedia presented the term "antipodes" or, as he said "antipodas" as referring to antichthones (people who lived on

10506-405: Was sufficient to produce granite melts by radiogenic heating , but recent work suggests that this is not a viable mechanism. In-situ granitization requires heating by the asthenospheric mantle or by underplating with mantle-derived magmas. Granite magmas have a density of 2.4 Mg/m , much less than the 2.8 Mg/m of high-grade metamorphic rock. This gives them tremendous buoyancy, so that ascent of

10609-564: Was supposed to occur across a migrating front. However, experimental work had established by the 1960s that granites were of igneous origin. The mineralogical and chemical features of granite can be explained only by crystal-liquid phase relations, showing that there must have been at least enough melting to mobilize the magma. However, at sufficiently deep crustal levels, the distinction between metamorphism and crustal melting itself becomes vague. Conditions for crystallization of liquid magma are close enough to those of high-grade metamorphism that

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