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105-585: Dalkey Quarry ( / ˈ d ɔː k i / DAW -kee ) is a long-disused 19th century granite quarry located on Dalkey Hill in the Dublin suburb of Dalkey , which was used to build several large maritime structures in south Dublin. Since passing into public ownership in the early 20th century and becoming part of Killiney Hill Park , it has become one of the most important rock climbing venues in Ireland, with over 350 graded routes, some of which are amongst

210-420: 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

315-563: 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

420-402: A binder. The abbreviation, AC , is sometimes used for asphalt concrete but can also denote asphalt content or asphalt cement , referring to the liquid asphalt portion of the composite material. Mixing of asphalt and aggregate is accomplished in one of several ways: In addition to the asphalt and aggregate, additives, such as polymers , and antistripping agents may be added to improve

525-459: A burst of new extremes including Donie O'Sullivan adding Ripsnorter (E5 6a), Asterisk (E6 6b), and doing Prisoner (E5 6a) without the peg runner to free what the guidebook calls "one of the best routes in the quarry"; Burke added Return of the Jedi (E5 6b). The mid-1990s saw the dominance of Ronan Browner in driving standards in the quarry, however, his attempts to introduce bolted climbs led to

630-520: 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,

735-517: 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

840-610: 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

945-565: 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

1050-824: 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

1155-536: 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

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1260-568: 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

1365-415: 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

1470-706: A second E7 to Dalkey with Slapstick (E7 6c). Browner continued to put up extreme new routes in the quarry. In 2000, he added a direct finish to Burke's 1994 classic Chomolungma (E6 6b), the Sans O2 Finish (E6 6c), In 2004, he added the classic Alexandria (E6 6b), and in the same year partnered with Hebblethwaite to add Lush (E7 6c), the third E7 in the quarry. Other long-standing problems were solved and gaps filled including Block Party (E7 6c) soloed in 2009 by Michael Duffy, and Captain Skyhook (E6 6b) in 2012 by Stephen McGowan. In 2020, Conor McGovern added

1575-617: A second E8 with his ascent of Blackberry Nightmare (E8 6c) in the East Valley beside Alexandria . While not noted for its bouldering routes, the quarry does have two areas, the "Ivy Chimney" section in the East Valley being the most popular area due to its ability to stay dry in damp conditions (its popularity dates from the pre-indoor climbing wall period), and the "Traverse Wall" in the West Valley that contains long and low warm-up routes. The problems are not boulders per se, but

1680-407: A showdown at the 1994 IMC AGM and a decision to ban bolts from all traditional Irish crags, of which Dalkey was one. In 1994, Browner instead used homemade pegs on his re-named Bitter Aftertaste (E6 6a, previously The Great Escape at F7a), and a year later on Indecent Assault (E7 6c, previously F7b+), the first E7 at the quarry, later considered E8 (one of Ireland's first). In 1999, Browner added

1785-466: 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

1890-545: 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

1995-517: 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

2100-454: Is a maintenance measure that helps keep water and petroleum products out of the pavement. Maintaining and cleaning ditches and storm drains will extend the life of the road at low cost. Sealing small cracks with bituminous crack sealer prevents water from enlarging cracks through frost weathering, or percolating down to the subbase and softening it. For somewhat more distressed roads, a chip seal or similar surface treatment may be applied. As

2205-776: Is a research program by the FHWA , which is specifically focusing on long-term pavement behaviour. Asphalt deterioration can include crocodile cracking , potholes , upheaval, raveling , bleeding , rutting , shoving, stripping , and grade depressions. In cold climates, frost heaves can crack asphalt even in one winter. Filling the cracks with bitumen is a temporary fix, but only proper compaction and drainage can slow this process. Factors that cause asphalt concrete to deteriorate over time mostly fall into one of three categories: construction quality, environmental considerations, and traffic loads. Often, damage results from combinations of factors in all three categories. Construction quality

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2310-456: Is an "engineering granite", suitable for the construction of harbours, breakwaters, lighthouses and slipways. Dalkey and Killiney quarries supplied the stone for many of these types of engineering projects in the Dublin area, and owing to their proximity to the sea, the stone easy to transport by ship. In the 1840s, stone from the quarry was exported to Newfoundland by Bishop Michael Fleming for

2415-410: 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

2520-637: 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

2625-434: 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

2730-415: Is critical to pavement performance. This includes the construction of utility trenches and appurtenances that are placed in the pavement after construction. Lack of compaction in the surface of the asphalt, especially on the longitudinal joint, can reduce the life of a pavement by 30 to 40%. Service trenches in pavements after construction have been said to reduce the life of the pavement by 50%, mainly due to

2835-651: Is due to its position as the most accessible outdoor rock climbing area for Dublin. Dalkey Quarry is a traditional climbing area with no bolted sport climbing routes, and the Mountaineering Ireland guidebook states that any newly placed manufactured bolts will be removed promptly. The availability of climbing protection varies but is generally considered good, and while some old pitons still remain (they are rarely replaced when they break), they should be treated with caution. Extreme climbers have used metal pegs hammered into existing cracks to reduce

2940-473: Is found on interstate highways where maintenance is highly crucial. Asphalt concrete generates less roadway noise than a Portland cement concrete surface, and is typically less noisy than chip seal surfaces. Because tire noise is generated through the conversion of kinetic energy to sound waves , more noise is produced as the speed of a vehicle increases. The notion that highway design might take into account acoustical engineering considerations, including

3045-433: 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

3150-404: 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

3255-454: 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

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3360-411: 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

3465-479: 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

3570-629: Is the Upper Cliffs. It can be accessed by the broad ridge that separates the East and West valleys (along which the quarry railway ran), or via a tarmac path from the Killiney Hill car-park, that passes an old signalling tower (British military tower to signal neighbouring Martello towers ), dropping steeply via a set of concrete steps to the base of the Upper Cliffs. The Upper Cliffs splits into three sub-sections, "Central Buttress" (overlooks

3675-410: 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

3780-489: 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

3885-409: 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

3990-428: 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

4095-420: Is why some agencies place the priority on preventive maintenance of roads in good condition, rather than reconstructing roads in poor condition. Poor roads are upgraded as resources and budget allow. In terms of lifetime cost and long term pavement conditions, this will result in better system performance. Agencies that concentrate on restoring their bad roads often find that by the time they have repaired them all,

4200-406: The subsoil to see how much load it can withstand. The pavement and subbase thicknesses are designed to withstand the wheel loads. Sometimes, geogrids are used to reinforce the subbase and further strengthen the roads. Drainage, including ditches , storm drains and underdrains are used to remove water from the roadbed, preventing it from weakening the subbase and subsoil. Sealcoating asphalt

4305-571: 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

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4410-604: The Department of Transportation to incorporate crumb rubber into asphalt paving materials. Other recycled materials that are actively included in asphalt concrete mixes across the United States include steel slag, blast furnace slag, and cellulose fibers. Further research has been conducted to discover new forms of waste that may be recycled into asphalt mixes. A 2020 study conducted in Melbourne, Australia presented

4515-401: The East Valley section is a "Far East Valley" section, however, it is on private property and closed to climbing. The East Valley section splits into the three sub-sections, "Ivy Chimney", "Eliminate Wall", and "Ghost Slab". The West Valley section splits into four sub-sections, "Pilaster", "Paradise Lost Slab", "Winder's Slab", and "Jameson 10 Wall". Directly above the East and West valleys

4620-592: The East Valley), "Tower Ridge" (between the two valleys), and the "White Wall" (overlooks the West Valley). Apart from the concrete steps down from the signalling tower to the Upper Cliffs section, the quarry is not landscaped and is left wild with extensive gorse and bramble growth, and thus no longer resembles a typical industrial quarry. The vegetation is home to wildlife, including foxes , and since 2014, peregrine falcons have sometimes nested in

4725-615: 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

4830-559: The United Kingdom and the Republic of Ireland) is a composite material commonly used to surface roads , parking lots , airports , and the core of embankment dams . Asphalt mixtures have been used in pavement construction since the beginning of the twentieth century. It consists of mineral aggregate bound together with bitumen (a substance also independently known as asphalt), laid in layers, and compacted. The process

4935-496: The United States contained, on average, 21.1% RAP and 0.2% RAS. Recycled asphalt components may be reclaimed and transported to an asphalt plant for processing and use in new pavements, or the entire recycling process may be conducted in-place. While in-place recycling typically occurs on roadways and is specific to RAP, recycling in asphalt plants may utilize RAP, RAS, or both. In 2019, an estimated 97.0 million tons of RAP and 1.1 million tons of RAS were accepted by asphalt plants in

5040-534: The United States. RAP is typically received by plants after being milled on-site, but pavements may also be ripped out in larger sections and crushed in the plant. RAP millings are typically stockpiled at plants before being incorporated into new asphalt mixes. Prior to mixing, stockpiled millings may be dried and any that have agglomerated in storage may have to be crushed. RAS may be received by asphalt plants as post-manufacturer waste directly from shingle factories, or they may be received as post-consumer waste at

5145-448: 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

5250-416: The United States. Many roofing shingles also contain asphalt, and asphalt concrete mixes may contain reclaimed asphalt shingles (RAS). Research has demonstrated that RAP and RAS can replace the need for up to 100% of the virgin aggregate and asphalt binder in a mix, but this percentage is typically lower due to regulatory requirements and performance concerns. In 2019, new asphalt pavement mixtures produced in

5355-506: The Upper Cliffs section; climbing in the vicinity of the nests is banned during the nesting periods. Routes are mainly single- pitch routes (there are some multi-pitch routes), and between 10–35 metres (33–115 ft) in length. The rock is granite and strongly jointed which means the rock is some parts is very solid whilst in other areas it is frail and friable. Routes vary in nature, with steep finger-cracks and bare slabs featuring prominently. Being granite (with some bands of quartz ),

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5460-723: The arrival of the Windrim brothers (Sean and Donal), with Sean putting up major classics such as Blazing Saddles (E2 5c) and The Ghost (E2 5b) in 1976, and The Shield (E2 5c) in 1978, described by the guidebook as "probably the most fallen off route in the quarry". The 1980s saw the arrival of a new generation that included Tony Burke (described in the MCI guidebook as "The Quarry Guru") who added Porn for Fun (E5 6a) and Hari Kari Groove (E3 5c) in 1985, and Howard Hebblethwaite (often climbing partner of Burke) who added Port Cullis (E4 6a) and Solitary Confinement (E5 6b) in 1985. 1990 saw

5565-441: The asphalt to oxidize, becoming stiffer and less resilient, leading to crack formation. Cold temperatures can cause cracks as the asphalt contracts. Cold asphalt is also less resilient and more vulnerable to cracking. Water trapped under the pavement softens the subbase and subgrade, making the road more vulnerable to traffic loads. Water under the road freezes and expands in cold weather, causing and enlarging cracks. In spring thaw,

5670-419: 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

5775-418: 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

5880-589: The climbing friction is good, but being quarried, it is not as good as fully weathered natural granite. The latest guidebook , published in 2005, lists about 300 routes, at grades up to E7, while the online guidebook contains over 350 routes with grades to E8 6c (e.g. Indecent Assault now regraded to E8). The number and density of routes in Dalkey Quarry is high given the size of the quarry (e.g. Fair Head 's 5 km long cliff has circa 450 routes, and Ailladie 's 1 km-long cliff has circa 200 routes), however, it

5985-669: The construction of the Basilica of St. John the Baptist in St. John's . In the 1860s, a two-ton foundation stone of Dalkey granite was used for the base of the O'Connell Monument in Dublin. The quarry was connected to Dún Laoghaire by a light railway , part of whose alignment was later used to build the Dalkey Atmospheric Railway . The remaining part of the route is now a public footpath known as The Metals, and much of

6090-543: The construction of the new harbour pier at nearby Dún Laoghaire , as well as for the construction of the South Bull Wall (part of the outer defences of Dublin Harbour) and as flagstone for Dublin streets. Dalkey granite is known for its hardness when compared to other granites, being "as hard as iron" according to Jim Murphy, a Dublin stonecutter interviewed in 1976. According to engineer John Hussey, Dalkey granite

6195-404: 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,

6300-473: 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

6405-508: The end of their service life. Processing of RAS includes grinding the shingles and sieving the grinds to remove oversized particles. The grinds may also be screened with a magnetic sieve to remove nails and other metal debris. The ground RAS is then dried, and the asphalt cement binder can be extracted. For further information on RAS processing, performance, and associated health and safety concerns, see Asphalt Shingles . In-place recycling methods allow roadways to be rehabilitated by reclaiming

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6510-691: The existing pavement, remixing, and repaving on-site. In-place recycling techniques include rubblizing , hot in-place recycling, cold in-place recycling, and full-depth reclamation . For further information on in-place methods, see Road Surface . During its service life, the asphalt cement binder, which makes up about 5–6% of a typical asphalt concrete mix, naturally hardens and becomes stiffer. This aging process primarily occurs due to oxidation, evaporation, exudation, and physical hardening. For this reason, asphalt mixes containing RAP and RAS are prone to exhibiting lower workability and increased susceptibility to fatigue cracking. These issues are avoidable if

6615-579: 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

6720-751: The first steps in the development of rock climbing in Ireland. The publication of the second IMC guidebook in 1949 saw many of the more obvious features climbed in the quarry. A new group of climbers pushed standards in the 1950s, with Fed Maguire, John Morrison, and Peter Kenny's 1951 ascent of Central Buttress (E1 4a, 5b, 4b), considered a milestone, and Kenny's 1951 ascents of Helios and Hyperion (both VS 4b), and Andre Kopczynski's 1952 ascent of In Abenstia (HVS 5a). In 1957, Paddy O'Leary put up Gargoyle Groove (HVS 5b). By 1964, Barry O'Flynn's fourth guidebook had 71 climbs which included more classic VS and HVS climbs from Maguire, Kopczynski, and others. The 1970s saw grades pushed even higher and particularly with

6825-414: The friction course. In general, the viscosity of asphalt allows it to conveniently form a convex surface, and a central apex to streets and roads to drain water to the edges. This is not, however, in itself an advantage over concrete, which has various grades of viscosity and can be formed into a convex road surface. Rather, it is the economy of asphalt concrete that renders it more frequently used. Concrete

6930-713: 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)

7035-400: The ground thaws from the top down, so water is trapped between the pavement above and the still-frozen soil underneath. This layer of saturated soil provides little support for the road above, leading to the formation of potholes. This is more of a problem for silty or clay soils than sandy or gravelly soils. Some jurisdictions pass frost laws to reduce the allowable weight of trucks during

7140-571: The harbour, quarrying only continued sporadically thereafter before finally ending in 1917. In 1914, the quarry was taken over by what is now known as Dún Laoghaire–Rathdown County Council (DLRCC), and most of the land was added to the existing Killiney Hill Park thus opening it up to the general public. In 1998, the DLRCC drew up proposals to turn the quarry's West Valley into a caravan halting site for travellers . The move met with opposition from local residents, climbers, and environmentalists, and

7245-409: The hardest single-pitch rock climbs in the country such as Indecent Assault ( E8 6c , one of Ireland's first-ever E8 routes , first ascended in 1995). The climbs are all traditional climbing routes and no bolted sport climbing routes are permitted, although some metal pegs are tolerated on the most extreme routes. Quarrying started in 1815–1817 on Dalkey Hill in order to supply granite for

7350-416: The lack of compaction in the trench, and also because of water intrusion through improperly sealed joints. Environmental factors include heat and cold, the presence of water in the subbase or subgrade soil underlying the pavement, and frost heaves. High temperatures soften the asphalt binder, allowing heavy tire loads to deform the pavement into ruts. Paradoxically, high heat and strong sunlight also cause

7455-474: 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

7560-729: 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

7665-435: 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

7770-426: 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

7875-408: 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 )

7980-405: 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,

8085-498: The mix's rutting resistance while maintaining adequate fatigue cracking resistance. In mixes with higher recycled content, the addition of virgin binder becomes less effective, and rejuvenators may be used. Rejuvenators are additives that restore the physical and chemical properties of the aged binder. When conventional mixing methods are used in asphalt plants, the upper limit for RAP content before rejuvenators become necessary has been estimated at 50%. Research has demonstrated that

8190-409: The number, width and length of cracks increases, more intensive repairs are needed. In order of generally increasing expense, these include thin asphalt overlays, multicourse overlays, grinding off the top course and overlaying, in-place recycling, or full-depth reconstruction of the roadway. It is far less expensive to keep a road in good condition than it is to repair it once it has deteriorated. This

8295-416: The original granite paving survives. A number of the houses on nearby Ardbrugh Road may have been originally built as quarry staff cottages, though most quarrymen originally squatted or lived in primitive tents. The quarry was the scene of major industrial action in the 1820s as quarry workers, who then numbered over 1,000 with their families, looked for better pay and conditions. After the construction of

8400-441: 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

8505-404: The pavement for controlling storm water. Different types of asphalt concrete have different performance characteristics in roads in terms of surface durability, tire wear, braking efficiency and roadway noise . In principle, the determination of appropriate asphalt performance characteristics must take into account the volume of traffic in each vehicle category, and the performance requirements of

8610-401: The performance aspects of RAP and RAS is to combine the recycled components with virgin aggregate and virgin asphalt binder. This approach can be effective when the recycled content in the mix is relatively low, and has a tendency to work more effectively with soft virgin binders. A 2020 study found that the addition of 5% RAS to a mix with a soft, low-grade virgin binder significantly increased

8715-495: The plans were eventually dropped. In May 2010, DLRCC angered climbers when they removed several large boulders from the quarry, disrupting climbing routes and potentially damaging other climbing routes in the process. There are three main climbing sections, the "Upper Cliffs", the "West Valley", and the "East Valley". Access to the West and East Valley sections is via the main entrance on Ardbrugh Road (just off Dalkey Avenue). Beside

8820-468: The properties of the final product. Areas paved with asphalt concrete—especially airport aprons —have been called "the tarmac" at times, despite not being constructed using the tarmacadam process. A variety of specialty asphalt concrete mixtures have been developed to meet specific needs, such as stone-matrix asphalt , which is designed to ensure a strong wearing surface, or porous asphalt pavements, which are permeable and allow water to drain through

8925-422: The recycled components are apportioned correctly in the mix. Practicing proper storage and handling, such as by keeping RAP stockpiles out of damp areas or direct sunlight, is also important in avoiding quality issues. The binder aging process may also produce some beneficial attributes, such as by contributing to higher levels of rutting resistance in asphalts containing RAP and RAS. One approach to balancing

9030-736: 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

9135-564: 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

9240-480: The risk on routes with almost no natural protection (e.g. Indecent Assault and Bitter Aftertaste ), which are tolerated and remain in place. In 1942, the quarry's first recorded climbs were made by members of the Irish Mountaineering Club (IMC), and a handwritten guidebook of thirteen routes was published that included Fifth Avenue (HS 4b), and Gwynne's Chimney (VS 4c). These routes were

9345-446: The road over a longer period of time, increasing ruts, cracking, and corrugations in the asphalt pavement. Other causes of damage include heat damage from vehicle fires, or solvent action from chemical spills. The life of a road can be prolonged through good design, construction and maintenance practices. During design, engineers measure the traffic on a road, paying special attention to the number and types of trucks. They also evaluate

9450-421: The roads that were in good condition have deteriorated. Some agencies use a pavement management system to help prioritize maintenance and repairs. Asphalt concrete is a recyclable material that can be reclaimed and reused both on-site and in asphalt plants . The most common recycled component in asphalt concrete is reclaimed asphalt pavement (RAP). RAP is recycled at a greater rate than any other material in

9555-418: 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

9660-414: 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

9765-492: 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

9870-398: The selection of the type of surface paving, arose in the early 1970s. With regard to structural performance, the asphalt behaviour depends on a variety of factors including the material, loading and environmental condition. Furthermore, the performance of pavement varies over time. Therefore, the long-term behaviour of asphalt pavement is different from its short-term performance. The LTPP

9975-404: The spring thaw season and protect their roads. The damage a vehicle causes is roughly proportional to the axle load raised to the fourth power, so doubling the weight an axle carries actually causes 16 times as much damage. Wheels cause the road to flex slightly, resulting in fatigue cracking, which often leads to crocodile cracking. Vehicle speed also plays a role. Slowly moving vehicles stress

10080-483: The start of traditional climbing routes, and low traverses across various walls. Boulder grades range from 3   to 7B+  (V8) (Ricky Bell's Super Pitch Shifter in the East Valley). In addition, several shorter traditional climbs are now ascended as highball bouldering problems with bouldering mats , popular candidates being Pilaster (VS 4c, 15m), Solitary Confinement (E5 6b, 14m), and Block Party (E7 6c, 7B  (V8), 9m). Granite Granite

10185-435: 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

10290-440: 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

10395-502: 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

10500-617: 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

10605-530: The use of rejuvenators at optimal doses can allow for mixes with 100% recycled components to meet the performance requirements of conventional asphalt concrete. Beyond RAP and RAS, a range of waste materials can be re-used in place of virgin aggregate, or as rejuvenators. Crumb rubber, generated from recycled tires, has been demonstrated to improve the fatigue resistance and flexural strength of asphalt mixes that contain RAP. In California, legislative mandates require

10710-514: 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." Asphalt concrete Asphalt concrete (commonly called asphalt , blacktop , or pavement in North America, and tarmac or bitumen macadam in

10815-674: Was refined and enhanced by Belgian-American inventor Edward De Smedt . Edgar Purnell Hooley further enhanced the process in the UK where the term tar macadam, shortened to tarmac was coined, after the name of his company Tar Macadam (Purnell Hooley's Patent) Syndicate Limited derived from the combination of tar and Macadam gravel composite mixtures. The terms asphalt (or asphaltic ) concrete , bituminous asphalt concrete , and bituminous mixture are typically used only in engineering and construction documents, which define concrete as any composite material composed of mineral aggregate adhered with

10920-405: 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

11025-564: 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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