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88-565: The mosque is located at Bd Sidi Mohammed Ben Abdallah in Casablanca. The 9-hectare (22-acre) complex nestles between the harbor and the El Hank Lighthouse . From the nearest train station at Casa-Port it is about a 20-minute walk to the mosque. The ten-lane boulevard with shopping avenues is at the southern facade of the mosque and extends to the gates of the Palace Oued el Makhazine in

176-553: 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

264-520: 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,

352-610: 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

440-512: A high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions . These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. 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

528-565: 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

616-820: 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

704-536: 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

792-595: A plastering technique which adds egg yolks and black soap into mixed plaster, was used in the hammam baths. The building blends Islamic architecture and Moroccan elements, and reflects Moorish influences, while featuring an urban design. It displays elements found in other Moroccan buildings such as the unfinished mosque in Rabat and the Koutoubia Mosque in Marrakesh . There are features from an old Roman fort converted into

880-568: 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

968-415: 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

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1056-448: A world record) and has a very quick setting time. This enabled the building of a taller structure with due underpinning of the foundation, while adhering to the construction schedule. Cranes were also designed to suit the height of the minaret for concreting. The museum opened its doors to the public after the construction of the mosque. It showcases art pieces from various traditional Moroccan arts as well as unused architectural elements of

1144-466: 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

1232-539: 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

1320-517: 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

1408-479: Is a substitute for the use of bricks, the material used in many other notable minarets, and has given the mosque an extraordinary elegance. Green tiles decorate the minaret for one third of the height from the top, and then changes colour to deep green or turquoise blue ; it is said that in the Hassan II minaret, the designer had used his sea-foam green and God's blue to celebrate the life of a king. The concrete used for

1496-405: Is also illuminated by light from the glass gates on the northern wall. The minaret is 210 metres (690 ft) tall and was the tallest minaret in the world when completed in 1993. It has a laser beam fitted at the top, which is electronically operated in the evening. It is oriented towards Mecca and has a range of 30 kilometres (19 mi). The minaret is said to enhance the visual alignment of

1584-410: 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

1672-618: 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

1760-434: 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

1848-400: Is equipped with a 2nd order Fresnel lens and the lighting apparatus has 6 panels of 0.70 m, rotating on mercury. With an intensity equivalent to 2.1 million candelas, the lighthouse has a luminous range of 30 nautical miles (about 55 kilometers). It emits three grouped flashes every 15 seconds. The lighthouse of El Hank is open to visitors and is one of the tourist highlights of Casablanca. It

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1936-467: Is known as the basilican plan, which is different from the common practice of a T-shaped plan adopted in many North African countries. The qibla wall is perpendicular to the naves which is said to be an unconventional layout, given that it is customary for the rows of worshipers facing Mecca to be as wide as possible rather than extend farther back (Halod and Khan 1997, 61). The adoption of this plan has been described as "a conflict between King Hassan II

2024-433: 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

2112-475: Is necessary to climb 256 steps to reach the upper platform. Identifier : ARLHS : MOR006 - Admiralty: D2574 - NGA : 23132. 33°36′36″N 7°39′17″W  /  33.6100°N 7.6547°W  / 33.6100; -7.6547 Granite Granite ( / ˈ ɡ r æ n ɪ t / GRAN -it ) is a coarse-grained ( phaneritic ) intrusive igneous rock composed mostly of quartz , alkali feldspar , and plagioclase . It forms from magma with

2200-404: 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

2288-454: 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

2376-511: Is retractable, illuminating the hall with daytime sunlight and allowing worshippers to pray under the stars on clear nights. It weighs 1100 tons and can be opened in five minutes; it measures 60 metres (200 ft) high, with an area of 3,400 square metres (37,000 sq ft). The roof is covered with cast-aluminium tiles, (similar to the Fez tiles ), stronger and more reliable than traditional ceramic tiles, and about 35 percent lighter. The prayer hall

2464-575: Is so large that it can easily accommodate the house of the Notre Dame of Paris or St Peter's of Rome . The woodcarvings, the zellij work and the stucco mouldings are of elaborate and highly impressive design; the wood used for carving is cedar from the middle Atlas Mountains , the marble is from Agadir and granite is brought from Tafraoute . The prayer hall is built to a rectangular plan of 200 metres (660 ft) length and 100 metres (330 ft) width with three naves , which are perpendicular to

2552-411: 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

2640-479: 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

2728-410: 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

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2816-455: 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

2904-428: 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

2992-453: The granite , plaster , marble , wood and other materials used in the construction, were extracted from around Morocco, with the exception of some Italian white granite columns and 56 glass chandeliers . Six thousand traditional Moroccan artisans worked for five years to create the abundant and beautiful mosaics , stone and marble floors and columns, sculpted plaster moldings, and carved and painted wood ceilings. The exterior surfaces of

3080-550: The qibla wall. The central nave of the hall is 40 metres (130 ft) and larger than the side naves which are 27 metres (89 ft) high. The central hall is undulating with a succession of numerous domes from which glass chandeliers , imported from Murano , are hung. On either side of the hall, there are mezzanine floors with carved dark wood furnishings, which are reserved for women. The doors are electrically operated. A "triptyich marble partition with open work and central window flanked by two smaller sized windows" are built on

3168-567: The 11th Rabi' al-Awwal of the year 1414 of the Hijra , corresponding to 30 August 1993, which also marked the eve of the anniversary of Prophet Muhammad ’s birth. It was dedicated to the Sovereign of Morocco . Construction costs, estimated to be about 585 million euro , were an issue of debate in Morocco, a lower mid-income country. While Hassan wished to build a mosque which would be second in size only to

3256-567: 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

3344-598: 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

3432-631: 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 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

3520-504: 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

3608-503: The ancient aristocrat and King Hassan II the contemporary leader who must develop commerce and industry in order meet the needs of his country." The prayer hall is on the top of the mosque covered in windows The central hall is centrally heated, and provides spectacular underwater views of the Atlantic Ocean. The decorations in the hall are elaborate and exquisite made possible by involving 6000 master artisans of Morocco working on it. It

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3696-505: The area are a madrasa (Islamic school), hammams (bathhouses), a museum on Moroccan history, conference halls, and a very large library said to be the "most comprehensive in the Islamic world." The 41 fountains in the courtyard are all well decorated. The garden around the mosque is well tended and is a popular location for family picnics. The traditionally designed madrasa occupies an area of 4,840 square metres (52,100 sq ft) including

3784-419: 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

3872-448: The basement. Two stories in height, it is constructed in a semi-circular shape, with abutting qibla wall and the mihrab section. The historical context of the mosque began with the death of King Mohammed V in 1961. King Hassan II had requested for the best of the country's artisans to come forward and submit plans for a mausoleum to honour the departed king; it should "reflect the fervor and veneration with which this illustrious man

3960-418: 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

4048-407: The boulevard. It is square in shape thrusting skyward. The base to the top width ratio of 1 to 8 (between basement and the summit) has a marble covering on the exterior with austere decoration. The faces of the facade have carved ornamentation with different materials. There are stitches of roudani tracetine on a 100,000 MP surface. This decorative material (with chrome and green as dominant colours),

4136-456: The creator on firm soil, can contemplate God's sky and ocean. The building was commissioned by King Hassan II to be the most ambitious structure ever built in Morocco. It was designed by the French architect Michel Pinseau who had lived in Morocco, and was constructed by the civil engineering group Bouygues. Work commenced on July 12, 1986, and was conducted over a seven-year period. Construction

4224-404: 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,

4312-476: The earlier one; total dyke quantity involved was 20,000 cubic metres (710,000 cu ft). All of these works involved use of 1300 tons of special steel (with 40 tons of Mo ) of 8–20 millimetres (0.31–0.79 in) bars with yield strength of 850 N per mm2. The concrete quantity poured involved 100,000 cubic metres (3,500,000 cu ft) of non-reinforced bulk concrete and 10,000 cubic metres (350,000 cu ft) of high-strength concrete. The entire work

4400-467: 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

4488-579: 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

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4576-416: The first phase a leak-proof coffer dam was constructed to isolate and dry the work area. This was built 5 metres (16 ft) below the highest water level. In the second phase, the voids seen in the prayer hall were filled with concrete. In the third phase, the structural slabs and pillars on the exterior part of mosque exposed to the sea were demolished; 6,000 cubic metres (210,000 cu ft) of concrete

4664-684: 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)

4752-570: The lighter color minerals. Occasionally some individual crystals ( phenocrysts ) are larger than the groundmass , in which case 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

4840-474: 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

4928-697: 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

5016-435: 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

5104-426: 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

5192-408: 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 )

5280-427: The main hall and another 80,000 in the plaza squares around it. Notable architectural features include the conspicuous columns, the horseshoe arches , and the innumerable muqarnas embellishing the ceilings. The dome, arches and walls give a grand ambiance to the mosque. The first-class sound system is discreetly hidden. The ablution room and a vast public hammam are in the basement, with its own entrance. Tadelakt ,

5368-405: 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,

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5456-478: The middle of the city. The basilical plan of the mosque justifies this layout of the boulevard. The mosque rises above the Atlantic Ocean. The building is built partially on land and partially over the ocean. This siting was accomplished by creating a platform linking a natural rock outcrop reclaimed from the sea, where the Orthlieb Pool had previously been located. Two large breakwaters were also built, to protect

5544-570: The minaret was a special high-grade type, which could perform well under severe conditions of a combined action of strong wind and seismicity. This was achieved by the Science Department of the Bouygues Group, the contractors for the project, who developed an extra-strength concrete four times stronger than ordinary concrete. Called B.H.P (highly resistant concrete), it offers a resistance to compression value of 1200 bars per sqcm (claimed to be

5632-432: The mosque at Mecca, the government lacked funds for such a grand project. Much of the financing was by public subscription. Twelve million people donated to the cause, with a receipt and certificate given to every donor. The smallest contribution was 5 DH . In addition to public donations and those from business establishments as well as other countries, western countries provided construction loans, which Morocco repaid. In

5720-446: The mosque display titanium , bronze , and granite finishes. It is ornamented with pale blue marble and Zellige tilework. A particular feature in the mosque is that all structures are made of reinforced cement concrete and all decorations are of traditional Moroccan design. The construction work involved engagement of 35,000 workers and working of over 50 million hours. The mosque has capacity to accommodate 25,000 devotees for prayers in

5808-423: The mosque from the erosive action of the ocean waves, which can be up to 10 metres (33 ft) in height. A temporary pier 800 metres (2,600 ft) in length had to be erected to protect the foundations of the pillars from the sea during the construction period. Its environmental advantage is that it is free of noise and pollution and receives a fresh breeze from the sea. Apart from the mosque, other structures in

5896-451: The mosque, such as carved stucco, painted wood ceilings, and zellij walls. Structural deterioration in the concrete wall was observed ten years after the mosque's completion. This was explained as being due to exposure to the salt water of the Atlantic Ocean, into which nearly half of the mosque's foundation projects. Salt water migrating into the porous concrete caused the rusting of the rebar steel reinforcements resulting in expansion of

5984-441: 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

6072-702: 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

6160-420: 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 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

6248-551: 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

6336-418: 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

6424-414: 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

6512-489: 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

6600-523: The steel and causing cracking of concrete. Salt water had penetrated beyond the steel bar into the structures as well. Effective restoration works were instituted in April 2005. This involved use of moly-grade stainless steel combined with high-grade concrete to make the structure resistant to chloride attack, a process that evolved during 3 years of research. This is expected to enhance the building's life by 100 years. The works were carried out in four phases. In

6688-435: 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

6776-769: The tomb of King Mohammed V of Rabat . Other elements come from the Tour Hassan Mosque , the Dome of the Rock (also known as Qubbat al Sakhra 688–692 AD), the Great Mosque of Madina (705–710 AD), Kairouan Mosque in Tunisia (663 AD), the Great Mosque of Damascus (705–715 AD), the Great Mosque of Cordoba (785–786 AD), Quarawiyyin Mosque (956 and 1135 AD) in Morocco, the Great Mosque of Tlemcen (1136), and Djamaa el Kebir (1096). Its layout

6864-502: 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

6952-599: 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

7040-659: The wall of the façade . Such panels, built with multicolored arches, engraved with ornamented floral designs, appear like a geometrical framework when viewed from the outside. The gates are embellished with marble bars which have faux voussoirs (alternately smooth or sculpted). The pillars of 13 metres (43 ft) height are square in shape with engaged columns and cruciform joining a series of pillars. Geometrically shaped polychromatic zellji with carved plaster are noted with floral and geometric designs with epigraphy. Carved or painted marble or shaped wood are used for these elegant designs, which highlight Islamic art forms. The roof

7128-463: The words of the authors of the book Morocco Country Study Guide , the Hassan II Mosque "undeniably marks the continuity of a modernized ancestral art and bears the sign of innovations that are due not only to technical reasons but also to a fertile exploration of new aesthetic possibilities." The building dimensions are 200 metres (660 ft) in length and 100 metres (330 ft) in width. All of

7216-560: Was done at a cost of 50 million euros. El Hank Lighthouse The El Hank lighthouse is a lighthouse located on the tip of El Hank, west of the port of Casablanca . It is managed by the Port and Maritime Authority within the Ministry of Equipment, Transport, Logistics and Water. This lighthouse, which bears the name of the point where it was built, is the tallest lighthouse in Morocco . It

7304-421: Was regarded." In 1980, during his birthday celebrations, Hassan II had made his ambitions very clear for creating a single landmark monument in Casablanca by stating: I wish Casablanca to be endowed with a large, fine building of which it can be proud until the end of time ... I want to build this mosque on the water, because God's throne is on the water. Therefore, the faithful who go there to pray, to praise

7392-663: Was removed. In the fourth phase, new exterior protection works were built using high-strength concrete with 2205 (conforming to UNS S 32205 EN 1.442 standards) stainless steel rods as reinforcements for effective erosion control. Even though the many structural changes were made as per detailed design, still during execution of works, 100 external pillars, called “combs” because of their wave breaking characteristics, were exposed to salt water and wave action and had to be replaced with new pillars. These were made from high-strength concrete with 2205 stainless steel reinforcements. This necessitated an additional leak-proof dyke to be built behind

7480-428: Was restored by the French architect Albert Laprade who redesigned the ridge and landscaped its surroundings in 1916, inspired by the ancient minarets. It came into operation in 1920 and helped the development of the city of Casablanca, as it facilitated access to the port, which was previously considered dangerous. The lighthouse of El Hank is 51 m high (with a base of 6.60 m) and has a diameter of 39 m at its base. It

7568-404: Was scheduled to be completed in 1989 ready for Hassan II's 60th birthday. During the most intense period of construction, 1400 men worked during the day and another 1100 during the night. 10,000 artists and craftsmen participated in building and beautifying the mosque. However, the building was not completed on schedule which delayed inauguration. The formal inauguration was subsequently chosen to be

7656-405: 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

7744-564: 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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