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115-494: The Anthracite Range is a laccolith, formed when magma intruded into sedimentary strata of the Mesaverde Formation approximately 30 million years ago. Subsequent erosion has removed the softer, overlying sedimentary rock thereby exposing the more resistant igneous rock that characterizes the mountain today. The range is composed of quartz monzonite porphyry and granodiorite porphyry. The Anthracite Range

230-647: A body-centred cubic structure at temperatures below 912 °C (1,674 °F), and a face-centred cubic structure between 912 and 1,394 °C (2,541 °F). Ice has fifteen known crystal structures, or fifteen solid phases, which exist at various temperatures and pressures. Glasses and other non-crystalline, amorphous solids without long-range order are not thermal equilibrium ground states; therefore they are described below as nonclassical states of matter. Solids can be transformed into liquids by melting, and liquids can be transformed into solids by freezing. Solids can also change directly into gases through

345-443: A cirque to the ridge just west of Unnamed Peak 11,555. From there, the summits are reached by hiking along the ridge. List of the most prominent summits of Colorado Magma Magma (from Ancient Greek μάγμα ( mágma )  'thick unguent ') is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as lava )

460-534: A dike , a sill , a laccolith , a pluton , or a batholith . While the study of magma has relied on observing magma after its transition into a lava flow , magma has been encountered in situ three times during geothermal drilling projects , twice in Iceland (see Use in energy production ) and once in Hawaii. Magma consists of liquid rock that usually contains suspended solid crystals. As magma approaches

575-414: A glass transition when heated towards the liquid state. Glasses can be made of quite different classes of materials: inorganic networks (such as window glass, made of silicate plus additives), metallic alloys, ionic melts , aqueous solutions , molecular liquids, and polymers . Thermodynamically, a glass is in a metastable state with respect to its crystalline counterpart. The conversion rate, however,

690-453: A magnetic domain ). If the domains are also aligned, the solid is a permanent magnet , which is magnetic even in the absence of an external magnetic field . The magnetization disappears when the magnet is heated to the Curie point , which for iron is 768 °C (1,414 °F). An antiferromagnet has two networks of equal and opposite magnetic moments, which cancel each other out so that

805-420: A phase transition . Water can be said to have several distinct solid states. The appearance of superconductivity is associated with a phase transition, so there are superconductive states. Likewise, ferromagnetic states are demarcated by phase transitions and have distinctive properties. When the change of state occurs in stages the intermediate steps are called mesophases . Such phases have been exploited by

920-500: A state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid , liquid , gas , and plasma . Many intermediate states are known to exist, such as liquid crystal , and some states only exist under extreme conditions, such as Bose–Einstein condensates and Fermionic condensates (in extreme cold), neutron-degenerate matter (in extreme density), and quark–gluon plasma (at extremely high energy ). Historically,

1035-439: A chemical equation, the state of matter of the chemicals may be shown as (s) for solid, (l) for liquid, and (g) for gas. An aqueous solution is denoted (aq), for example, Matter in the plasma state is seldom used (if at all) in chemical equations, so there is no standard symbol to denote it. In the rare equations that plasma is used it is symbolized as (p). Glass is a non-crystalline or amorphous solid material that exhibits

1150-456: A combination of these processes. Other mechanisms, such as melting from a meteorite impact , are less important today, but impacts during the accretion of the Earth led to extensive melting, and the outer several hundred kilometers of the early Earth was probably a magma ocean . Impacts of large meteorites in the last few hundred million years have been proposed as one mechanism responsible for

1265-420: A depth of 2,488 m (8,163 ft). The temperature of this magma was estimated at 1,050 °C (1,920 °F). Temperatures of deeper magmas must be inferred from theoretical computations and the geothermal gradient. Most magmas contain some solid crystals suspended in the liquid phase. This indicates that the temperature of the magma lies between the solidus , which is defined as the temperature at which

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1380-427: A dissolved water content in excess of 10%. Water is somewhat less soluble in low-silica magma than high-silica magma, so that at 1,100 °C and 0.5 GPa , a basaltic magma can dissolve 8% H 2 O while a granite pegmatite magma can dissolve 11% H 2 O . However, magmas are not necessarily saturated under typical conditions. Carbon dioxide is much less soluble in magmas than water, and frequently separates into

1495-406: A distinct fluid phase even at great depth. This explains the presence of carbon dioxide fluid inclusions in crystals formed in magmas at great depth. Viscosity is a key melt property in understanding the behaviour of magmas. Whereas temperatures in common silicate lavas range from about 800 °C (1,470 °F) for felsic lavas to 1,200 °C (2,190 °F) for mafic lavas, the viscosity of

1610-408: A given liquid can exist is its critical temperature . A gas is a compressible fluid. Not only will a gas conform to the shape of its container but it will also expand to fill the container. In a gas, the molecules have enough kinetic energy so that the effect of intermolecular forces is small (or zero for an ideal gas ), and the typical distance between neighboring molecules is much greater than

1725-405: A heavier analogue of the common down quark . It may be stable at lower energy states once formed, although this is not known. Quark–gluon plasma is a very high-temperature phase in which quarks become free and able to move independently, rather than being perpetually bound into particles, in a sea of gluons , subatomic particles that transmit the strong force that binds quarks together. This

1840-435: A high charge (the high-field-strength elements, or HSFEs), which include such elements as zirconium , niobium , hafnium , tantalum , the rare-earth elements , and the actinides . Potassium can become so enriched in melt produced by a very low degree of partial melting that, when the magma subsequently cools and solidifies, it forms unusual potassic rock such as lamprophyre , lamproite , or kimberlite . When enough rock

1955-546: A hypothetical magma formed entirely from melted silica, NBO/T would be 0, while in a hypothetical magma so low in network formers that no polymerization takes place, NBO/T would be 4. Neither extreme is common in nature, but basalt magmas typically have NBO/T between 0.6 and 0.9, andesitic magmas have NBO/T of 0.3 to 0.5, and rhyolitic magmas have NBO/T of 0.02 to 0.2. Water acts as a network modifier, and dissolved water drastically reduces melt viscosity. Carbon dioxide neutralizes network modifiers, so dissolved carbon dioxide increases

2070-481: A layer that appears to contain silicate melt and that stretches for at least 1,000 kilometers within the middle crust along the southern margin of the Tibetan Plateau. Granite and rhyolite are types of igneous rock commonly interpreted as products of the melting of continental crust because of increases in temperature. Temperature increases also may contribute to the melting of lithosphere dragged down in

2185-518: A liquid (or solid), in which case the gas pressure equals the vapor pressure of the liquid (or solid). A supercritical fluid (SCF) is a gas whose temperature and pressure are above the critical temperature and critical pressure respectively. In this state, the distinction between liquid and gas disappears. A supercritical fluid has the physical properties of a gas, but its high density confers solvent properties in some cases, which leads to useful applications. For example, supercritical carbon dioxide

2300-440: A liquid at its melting point , boils into a gas at its boiling point , and if heated high enough would enter a plasma state in which the electrons are so energized that they leave their parent atoms. Forms of matter that are not composed of molecules and are organized by different forces can also be considered different states of matter. Superfluids (like Fermionic condensate ) and the quark–gluon plasma are examples. In

2415-494: A liquid, but exhibiting long-range order. For example, the nematic phase consists of long rod-like molecules such as para-azoxyanisole , which is nematic in the temperature range 118–136 °C (244–277 °F). In this state the molecules flow as in a liquid, but they all point in the same direction (within each domain) and cannot rotate freely. Like a crystalline solid, but unlike a liquid, liquid crystals react to polarized light. Other types of liquid crystals are described in

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2530-420: A magma. In practice, it is difficult to unambiguously identify primary magmas, though it has been suggested that boninite is a variety of andesite crystallized from a primary magma. The Great Dyke of Zimbabwe has also been interpreted as rock crystallized from a primary magma. The interpretation of leucosomes of migmatites as primary magmas is contradicted by zircon data, which suggests leucosomes are

2645-582: A phenomenon known as the Meissner effect or perfect diamagnetism . Superconducting magnets are used as electromagnets in magnetic resonance imaging machines. The phenomenon of superconductivity was discovered in 1911, and for 75 years was only known in some metals and metallic alloys at temperatures below 30 K. In 1986 so-called high-temperature superconductivity was discovered in certain ceramic oxides, and has now been observed in temperatures as high as 164 K. Close to absolute zero, some liquids form

2760-439: A residue (a cumulate rock ) left by extraction of a primary magma. When it is impossible to find the primitive or primary magma composition, it is often useful to attempt to identify a parental magma. A parental magma is a magma composition from which the observed range of magma chemistries has been derived by the processes of igneous differentiation . It need not be a primitive melt. State of matter In physics ,

2875-425: A rock type commonly enriched in incompatible elements. Bowen's reaction series is important for understanding the idealised sequence of fractional crystallisation of a magma. Magma composition can be determined by processes other than partial melting and fractional crystallization. For instance, magmas commonly interact with rocks they intrude, both by melting those rocks and by reacting with them. Assimilation near

2990-438: A second liquid state described as superfluid because it has zero viscosity (or infinite fluidity; i.e., flowing without friction). This was discovered in 1937 for helium , which forms a superfluid below the lambda temperature of 2.17 K (−270.98 °C; −455.76 °F). In this state it will attempt to "climb" out of its container. It also has infinite thermal conductivity so that no temperature gradient can form in

3105-567: A solidified crust. Most basalt lavas are of ʻAʻā or pāhoehoe types, rather than block lavas. Underwater, they can form pillow lavas , which are rather similar to entrail-type pahoehoe lavas on land. Ultramafic magmas, such as picritic basalt, komatiite , and highly magnesian magmas that form boninite , take the composition and temperatures to the extreme. All have a silica content under 45%. Komatiites contain over 18% magnesium oxide, and are thought to have erupted at temperatures of 1,600 °C (2,910 °F). At this temperature there

3220-430: A string-net liquid, atoms have apparently unstable arrangement, like a liquid, but are still consistent in overall pattern, like a solid. When in a normal solid state, the atoms of matter align themselves in a grid pattern, so that the spin of any electron is the opposite of the spin of all electrons touching it. But in a string-net liquid, atoms are arranged in some pattern that requires some electrons to have neighbors with

3335-407: A subduction zone. When rocks melt, they do so over a range of temperature, because most rocks are made of several minerals , which all have different melting points. The temperature at which the first melt appears (the solidus) is lower than the melting temperature of any one of the pure minerals. This is similar to the lowering of the melting point of ice when it is mixed with salt. The first melt

3450-481: A superdense conglomeration of neutrons. Normally free neutrons outside an atomic nucleus will decay with a half life of approximately 10 minutes, but in a neutron star, the decay is overtaken by inverse decay. Cold degenerate matter is also present in planets such as Jupiter and in the even more massive brown dwarfs , which are expected to have a core with metallic hydrogen . Because of the degeneracy, more massive brown dwarfs are not significantly larger. In metals,

3565-467: A superfluid. Placing a superfluid in a spinning container will result in quantized vortices . These properties are explained by the theory that the common isotope helium-4 forms a Bose–Einstein condensate (see next section) in the superfluid state. More recently, fermionic condensate superfluids have been formed at even lower temperatures by the rare isotope helium-3 and by lithium-6 . In 1924, Albert Einstein and Satyendra Nath Bose predicted

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3680-439: A tetrahedral arrangement around the much smaller silicon ion. This is called a silica tetrahedron . In a magma that is low in silicon, these silica tetrahedra are isolated, but as the silicon content increases, silica tetrahedra begin to partially polymerize, forming chains, sheets, and clumps of silica tetrahedra linked by bridging oxygen ions. These greatly increase the viscosity of the magma. The tendency towards polymerization

3795-638: A typical viscosity of 3.5 × 10 cP (3,500 Pa⋅s) at 1,200 °C (2,190 °F). This is slightly greater than the viscosity of smooth peanut butter . Intermediate magmas show a greater tendency to form phenocrysts . Higher iron and magnesium tends to manifest as a darker groundmass , including amphibole or pyroxene phenocrysts. Mafic or basaltic magmas have a silica content of 52% to 45%. They are typified by their high ferromagnesian content, and generally erupt at temperatures of 1,100 to 1,200 °C (2,010 to 2,190 °F). Viscosities can be relatively low, around 10 to 10 cP (10 to 100 Pa⋅s), although this

3910-417: A uniform liquid. Transition metal atoms often have magnetic moments due to the net spin of electrons that remain unpaired and do not form chemical bonds. In some solids the magnetic moments on different atoms are ordered and can form a ferromagnet, an antiferromagnet or a ferrimagnet. In a ferromagnet —for instance, solid iron —the magnetic moment on each atom is aligned in the same direction (within

4025-633: A viscosity of about 1 cP (0.001 Pa⋅s). Because of this very high viscosity, felsic lavas usually erupt explosively to produce pyroclastic (fragmental) deposits. However, rhyolite lavas occasionally erupt effusively to form lava spines , lava domes or "coulees" (which are thick, short lava flows). The lavas typically fragment as they extrude, producing block lava flows . These often contain obsidian . Felsic lavas can erupt at temperatures as low as 800 °C (1,470 °F). Unusually hot (>950 °C; >1,740 °F) rhyolite lavas, however, may flow for distances of many tens of kilometres, such as in

4140-442: Is a disordered state in a system of interacting quantum spins which preserves its disorder to very low temperatures, unlike other disordered states. It is not a liquid in physical sense, but a solid whose magnetic order is inherently disordered. The name "liquid" is due to an analogy with the molecular disorder in a conventional liquid. A QSL is neither a ferromagnet , where magnetic domains are parallel, nor an antiferromagnet , where

4255-399: Is a type of matter theorized to exist in atomic nuclei traveling near the speed of light. According to Einstein's theory of relativity, a high-energy nucleus appears length contracted, or compressed, along its direction of motion. As a result, the gluons inside the nucleus appear to a stationary observer as a "gluonic wall" traveling near the speed of light. At very high energies, the density of

4370-409: Is added to the rock, the temperature remains at 1274 °C until either the anorthite or diopside is fully melted. The temperature then rises as the remaining mineral continues to melt, which shifts the melt composition away from the eutectic. For example, if the content of anorthite is greater than 43%, the entire supply of diopside will melt at 1274 °C., along with enough of the anorthite to keep

4485-419: Is analogous to the liberation of electrons from atoms in a plasma. This state is briefly attainable in extremely high-energy heavy ion collisions in particle accelerators , and allows scientists to observe the properties of individual quarks. Theories predicting the existence of quark–gluon plasma were developed in the late 1970s and early 1980s, and it was detected for the first time in the laboratory at CERN in

4600-536: Is assumed that essentially all electrons are "free", and that a very high-energy plasma is essentially bare nuclei swimming in a sea of electrons. This forms the so-called fully ionised plasma. The plasma state is often misunderstood, and although not freely existing under normal conditions on Earth, it is quite commonly generated by either lightning , electric sparks , fluorescent lights , neon lights or in plasma televisions . The Sun's corona , some types of flame , and stars are all examples of illuminated matter in

4715-444: Is called the eutectic and has a composition that depends on the combination of minerals present. For example, a mixture of anorthite and diopside , which are two of the predominant minerals in basalt , begins to melt at about 1274 °C. This is well below the melting temperatures of 1392 °C for pure diopside and 1553 °C for pure anorthite. The resulting melt is composed of about 43 wt% anorthite. As additional heat

Anthracite Range - Misplaced Pages Continue

4830-410: Is concentrated in a thin layer in the toothpaste next to the tube, and only here does the toothpaste behave as a fluid. Thixotropic behavior also hinders crystals from settling out of the magma. Once the crystal content reaches about 60%, the magma ceases to behave like a fluid and begins to behave like a solid. Such a mixture of crystals with melted rock is sometimes described as crystal mush . Magma

4945-462: Is driven out of the oceanic lithosphere in subduction zones , and it causes melting in the overlying mantle. Hydrous magmas with the composition of basalt or andesite are produced directly and indirectly as results of dehydration during the subduction process. Such magmas, and those derived from them, build up island arcs such as those in the Pacific Ring of Fire . These magmas form rocks of

5060-417: Is expressed as NBO/T, where NBO is the number of non-bridging oxygen ions and T is the number of network-forming ions. Silicon is the main network-forming ion, but in magmas high in sodium, aluminium also acts as a network former, and ferric iron can act as a network former when other network formers are lacking. Most other metallic ions reduce the tendency to polymerize and are described as network modifiers. In

5175-542: Is found beneath the surface of the Earth , and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites . Besides molten rock, magma may also contain suspended crystals and gas bubbles . Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones , continental rift zones , mid-ocean ridges and hotspots . Mantle and crustal melts migrate upwards through

5290-417: Is magma extruded onto the surface, are almost all in the range 700 to 1,400 °C (1,300 to 2,600 °F), but very rare carbonatite magmas may be as cool as 490 °C (910 °F), and komatiite magmas may have been as hot as 1,600 °C (2,900 °F). Magma has occasionally been encountered during drilling in geothermal fields, including drilling in Hawaii that penetrated a dacitic magma body at

5405-647: Is melted before the heat supply is exhausted. Pegmatite may be produced by low degrees of partial melting of the crust. Some granite -composition magmas are eutectic (or cotectic) melts, and they may be produced by low to high degrees of partial melting of the crust, as well as by fractional crystallization . Most magmas are fully melted only for small parts of their histories. More typically, they are mixes of melt and crystals, and sometimes also of gas bubbles. Melt, crystals, and bubbles usually have different densities, and so they can separate as magmas evolve. As magma cools, minerals typically crystallize from

5520-416: Is melted, the small globules of melt (generally occurring between mineral grains) link up and soften the rock. Under pressure within the earth, as little as a fraction of a percent of partial melting may be sufficient to cause melt to be squeezed from its source. Melt rapidly separates from its source rock once the degree of partial melting exceeds 30%. However, usually much less than 30% of a magma source rock

5635-415: Is no long-range magnetic order. Superconductors are materials which have zero electrical resistivity , and therefore perfect conductivity. This is a distinct physical state which exists at low temperature, and the resistivity increases discontinuously to a finite value at a sharply-defined transition temperature for each superconductor. A superconductor also excludes all magnetic fields from its interior,

5750-421: Is possible for a single compound to form different phases that are in the same state of matter. For example, ice is the solid state of water, but there are multiple phases of ice with different crystal structures , which are formed at different pressures and temperatures. In a solid, constituent particles (ions, atoms, or molecules) are closely packed together. The forces between particles are so strong that

5865-634: Is practically no polymerization of the mineral compounds, creating a highly mobile liquid. Viscosities of komatiite magmas are thought to have been as low as 100 to 1000 cP (0.1 to 1 Pa⋅s), similar to that of light motor oil. Most ultramafic lavas are no younger than the Proterozoic , with a few ultramafic magmas known from the Phanerozoic in Central America that are attributed to a hot mantle plume . No modern komatiite lavas are known, as

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5980-446: Is practically zero. A plastic crystal is a molecular solid with long-range positional order but with constituent molecules retaining rotational freedom; in an orientational glass this degree of freedom is frozen in a quenched disordered state. Similarly, in a spin glass magnetic disorder is frozen. Liquid crystal states have properties intermediate between mobile liquids and ordered solids. Generally, they are able to flow like

6095-448: Is still many orders of magnitude higher than water. This viscosity is similar to that of ketchup . Basalt lavas tend to produce low-profile shield volcanoes or flood basalts , because the fluidal lava flows for long distances from the vent. The thickness of a basalt lava, particularly on a low slope, may be much greater than the thickness of the moving lava flow at any one time, because basalt lavas may "inflate" by supply of lava beneath

6210-413: Is typically also viscoelastic , meaning it flows like a liquid under low stresses, but once the applied stress exceeds a critical value, the melt cannot dissipate the stress fast enough through relaxation alone, resulting in transient fracture propagation. Once stresses are reduced below the critical threshold, the melt viscously relaxes once more and heals the fracture. Temperatures of molten lava, which

6325-408: Is typically the most abundant magmatic gas, followed by carbon dioxide and sulfur dioxide . Other principal magmatic gases include hydrogen sulfide , hydrogen chloride , and hydrogen fluoride . The solubility of magmatic gases in magma depends on pressure, magma composition, and temperature. Magma that is extruded as lava is extremely dry, but magma at depth and under great pressure can contain

6440-478: Is used to extract caffeine in the manufacture of decaffeinated coffee. A gas is usually converted to a plasma in one of two ways, either from a huge voltage difference between two points, or by exposing it to extremely high temperatures. Heating matter to high temperatures causes electrons to leave the atoms, resulting in the presence of free electrons. This creates a so-called partially ionised plasma. At very high temperatures, such as those present in stars, it

6555-678: The Snake River Plain of the northwestern United States. Intermediate or andesitic magmas contain 52% to 63% silica, and are lower in aluminium and usually somewhat richer in magnesium and iron than felsic magmas. Intermediate lavas form andesite domes and block lavas, and may occur on steep composite volcanoes , such as in the Andes . They are also commonly hotter, in the range of 850 to 1,100 °C (1,560 to 2,010 °F)). Because of their lower silica content and higher eruptive temperatures, they tend to be much less viscous, with

6670-576: The University of Colorado at Boulder , produced the first such condensate experimentally. A Bose–Einstein condensate is "colder" than a solid. It may occur when atoms have very similar (or the same) quantum levels , at temperatures very close to absolute zero , −273.15 °C (−459.67 °F). A fermionic condensate is similar to the Bose–Einstein condensate but composed of fermions . The Pauli exclusion principle prevents fermions from entering

6785-466: The baryon asymmetry in the universe, but little is known about it. In string theory , a Hagedorn temperature is predicted for superstrings at about 10 K, where superstrings are copiously produced. At Planck temperature (10 K), gravity becomes a significant force between individual particles. No current theory can describe these states and they cannot be produced with any foreseeable experiment. However, these states are important in cosmology because

6900-458: The calc-alkaline series, an important part of the continental crust . With low density and viscosity, hydrous magmas are highly buoyant and will move upwards in Earth's mantle. The addition of carbon dioxide is relatively a much less important cause of magma formation than the addition of water, but genesis of some silica-undersaturated magmas has been attributed to the dominance of carbon dioxide over water in their mantle source regions. In

7015-453: The convection of solid mantle, it will cool slightly as it expands in an adiabatic process , but the cooling is only about 0.3 °C per kilometer. Experimental studies of appropriate peridotite samples document that the solidus temperatures increase by 3 °C to 4 °C per kilometer. If the rock rises far enough, it will begin to melt. Melt droplets can coalesce into larger volumes and be intruded upwards. This process of melting from

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7130-438: The "Bose–Einstein condensate" (BEC), sometimes referred to as the fifth state of matter. In a BEC, matter stops behaving as independent particles, and collapses into a single quantum state that can be described with a single, uniform wavefunction. In the gas phase, the Bose–Einstein condensate remained an unverified theoretical prediction for many years. In 1995, the research groups of Eric Cornell and Carl Wieman , of JILA at

7245-543: The Anthracite Range High Point (elevation 12,385 ft (3,775 m)), prominence 2,125 ft (648 m)); Unnamed Peak 12,300 (elevation 12,300 ft (3,700 m)); Ohio Peak (elevation 12,271 ft (3,740 m)); and Unnamed Peak 11,555 (elevation 11,555 ft (3,522 m)). These summits are most often accessed from Ohio Pass where a climber's trail enters the wilderness area, traverses southwest across talus slopes then up through

7360-472: The Earth's mantle has cooled too much to produce highly magnesian magmas. Some silicic magmas have an elevated content of alkali metal oxides (sodium and potassium), particularly in regions of continental rifting , areas overlying deeply subducted plates , or at intraplate hotspots . Their silica content can range from ultramafic ( nephelinites , basanites and tephrites ) to felsic ( trachytes ). They are more likely to be generated at greater depths in

7475-465: The Earth's upper crust, but this varies widely by region, from a low of 5–10 °C/km within oceanic trenches and subduction zones to 30–80 °C/km along mid-ocean ridges or near mantle plumes . The gradient becomes less steep with depth, dropping to just 0.25 to 0.3 °C/km in the mantle, where slow convection efficiently transports heat. The average geothermal gradient is not normally steep enough to bring rocks to their melting point anywhere in

7590-476: The anorthite is melted. If the anorthite content of the mixture is less than 43%, then all the anorthite will melt at the eutectic temperature, along with part of the diopside, and the remaining diopside will then gradually melt as the temperature continues to rise. Because of eutectic melting, the composition of the melt can be quite different from the source rock. For example, a mixture of 10% anorthite with diopside could experience about 23% partial melting before

7705-714: The blocks, block copolymers undergo a similar phase separation. However, because the blocks are covalently bonded to each other, they cannot demix macroscopically as water and oil can, and so instead the blocks form nanometre-sized structures. Depending on the relative lengths of each block and the overall block topology of the polymer, many morphologies can be obtained, each its own phase of matter. Ionic liquids also display microphase separation. The anion and cation are not necessarily compatible and would demix otherwise, but electric charge attraction prevents them from separating. Their anions and cations appear to diffuse within compartmentalized layers or micelles instead of freely as in

7820-458: The crust or upper mantle, so magma is produced only where the geothermal gradient is unusually steep or the melting point of the rock is unusually low. However, the ascent of magma towards the surface in such settings is the most important process for transporting heat through the crust of the Earth. Rocks may melt in response to a decrease in pressure, to a change in composition (such as an addition of water), to an increase in temperature, or to

7935-432: The crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by fractional crystallization , contamination with crustal melts, magma mixing, and degassing. Following its ascent through the crust, magma may feed a volcano and be extruded as lava, or it may solidify underground to form an intrusion , such as

8050-455: The crystallization process would not change the overall composition of the melt plus solid minerals. This situation is described as equillibrium crystallization . However, in a series of experiments culminating in his 1915 paper, Crystallization-differentiation in silicate liquids , Norman L. Bowen demonstrated that crystals of olivine and diopside that crystallized out of a cooling melt of forsterite , diopside, and silica would sink through

8165-507: The distinction is based on qualitative differences in properties. Matter in the solid state maintains a fixed volume (assuming no change in temperature or air pressure) and shape, with component particles ( atoms , molecules or ions ) close together and fixed into place. Matter in the liquid state maintains a fixed volume (assuming no change in temperature or air pressure), but has a variable shape that adapts to fit its container. Its particles are still close together but move freely. Matter in

8280-572: The electrons can be modeled as a degenerate gas moving in a lattice of non-degenerate positive ions. In regular cold matter, quarks , fundamental particles of nuclear matter, are confined by the strong force into hadrons that consist of 2–4 quarks, such as protons and neutrons. Quark matter or quantum chromodynamical (QCD) matter is a group of phases where the strong force is overcome and quarks are deconfined and free to move. Quark matter phases occur at extremely high densities or temperatures, and there are no known ways to produce them in equilibrium in

8395-399: The eutectic temperature of 1274 °C. This shifts the remaining melt towards its eutectic composition of 43% diopside. The eutectic is reached at 1274 °C, the temperature at which diopside and anorthite begin crystallizing together. If the melt was 90% diopside, the diopside would begin crystallizing first until the eutectic was reached. If the crystals remained suspended in the melt,

8510-512: The extensive basalt magmatism of several large igneous provinces. Decompression melting occurs because of a decrease in pressure. It is the most important mechanism for producing magma from the upper mantle. The solidus temperatures of most rocks (the temperatures below which they are completely solid) increase with increasing pressure in the absence of water. Peridotite at depth in the Earth's mantle may be hotter than its solidus temperature at some shallower level. If such rock rises during

8625-412: The gaseous state has both variable volume and shape, adapting both to fit its container. Its particles are neither close together nor fixed in place. Matter in the plasma state has variable volume and shape, and contains neutral atoms as well as a significant number of ions and electrons , both of which can move around freely. The term phase is sometimes used as a synonym for state of matter, but it

8740-529: The gluons in this wall is seen to increase greatly. Unlike the quark–gluon plasma produced in the collision of such walls, the color-glass condensate describes the walls themselves, and is an intrinsic property of the particles that can only be observed under high-energy conditions such as those at RHIC and possibly at the Large Hadron Collider as well. Various theories predict new states of matter at very high energies. An unknown state has created

8855-430: The gravitational force increases, but pressure does not increase proportionally. Electron-degenerate matter is found inside white dwarf stars. Electrons remain bound to atoms but are able to transfer to adjacent atoms. Neutron-degenerate matter is found in neutron stars . Vast gravitational pressure compresses atoms so strongly that the electrons are forced to combine with protons via inverse beta-decay, resulting in

8970-420: The importance of each mechanism being a topic of continuing research. The change of rock composition most responsible for the creation of magma is the addition of water. Water lowers the solidus temperature of rocks at a given pressure. For example, at a depth of about 100 kilometers, peridotite begins to melt near 800 °C in the presence of excess water, but near 1,500 °C in the absence of water. Water

9085-424: The introduction of liquid crystal technology. The state or phase of a given set of matter can change depending on pressure and temperature conditions, transitioning to other phases as these conditions change to favor their existence; for example, solid transitions to liquid with an increase in temperature. Near absolute zero , a substance exists as a solid . As heat is added to this substance it melts into

9200-490: The laboratory; in ordinary conditions, any quark matter formed immediately undergoes radioactive decay. Strange matter is a type of quark matter that is suspected to exist inside some neutron stars close to the Tolman–Oppenheimer–Volkoff limit (approximately 2–3 solar masses ), although there is no direct evidence of its existence. In strange matter, part of the energy available manifests as strange quarks ,

9315-476: The magma completely solidifies, and the liquidus , defined as the temperature at which the magma is completely liquid. Calculations of solidus temperatures at likely depths suggests that magma generated beneath areas of rifting starts at a temperature of about 1,300 to 1,500 °C (2,400 to 2,700 °F). Magma generated from mantle plumes may be as hot as 1,600 °C (2,900 °F). The temperature of magma generated in subduction zones, where water vapor lowers

9430-408: The magma. Gabbro may have a liquidus temperature near 1,200 °C, and the derivative granite-composition melt may have a liquidus temperature as low as about 700 °C. Incompatible elements are concentrated in the last residues of magma during fractional crystallization and in the first melts produced during partial melting: either process can form the magma that crystallizes to pegmatite ,

9545-435: The magnetic domains are antiparallel; instead, the magnetic domains are randomly oriented. This can be realized e.g. by geometrically frustrated magnetic moments that cannot point uniformly parallel or antiparallel. When cooling down and settling to a state, the domain must "choose" an orientation, but if the possible states are similar in energy, one will be chosen randomly. Consequently, despite strong short-range order, there

9660-453: The main article on these states. Several types have technological importance, for example, in liquid crystal displays . Copolymers can undergo microphase separation to form a diverse array of periodic nanostructures, as shown in the example of the styrene-butadiene-styrene block copolymer shown at right. Microphase separation can be understood by analogy to the phase separation between oil and water. Due to chemical incompatibility between

9775-419: The mantle than subalkaline magmas. Olivine nephelinite magmas are both ultramafic and highly alkaline, and are thought to have come from much deeper in the mantle of the Earth than other magmas. Tholeiitic basalt magma Rhyolite magma Some lavas of unusual composition have erupted onto the surface of the Earth. These include: The concentrations of different gases can vary considerably. Water vapor

9890-424: The melt at different temperatures. This resembles the original melting process in reverse. However, because the melt has usually separated from its original source rock and moved to a shallower depth, the reverse process of crystallization is not precisely identical. For example, if a melt was 50% each of diopside and anorthite, then anorthite would begin crystallizing from the melt at a temperature somewhat higher than

10005-438: The melt at the eutectic composition. Further heating causes the temperature to slowly rise as the remaining anorthite gradually melts and the melt becomes increasingly rich in anorthite liquid. If the mixture has only a slight excess of anorthite, this will melt before the temperature rises much above 1274 °C. If the mixture is almost all anorthite, the temperature will reach nearly the melting point of pure anorthite before all

10120-449: The melt deviated from the eutectic, which has the composition of about 43% anorthite. This effect of partial melting is reflected in the compositions of different magmas. A low degree of partial melting of the upper mantle (2% to 4%) can produce highly alkaline magmas such as melilitites , while a greater degree of partial melting (8% to 11%) can produce alkali olivine basalt. Oceanic magmas likely result from partial melting of 3% to 15% of

10235-402: The melt on geologically relevant time scales. Geologists subsequently found considerable field evidence of such fractional crystallization . When crystals separate from a magma, then the residual magma will differ in composition from the parent magma. For instance, a magma of gabbroic composition can produce a residual melt of granitic composition if early formed crystals are separated from

10350-429: The melting temperature, may be as low as 1,060 °C (1,940 °F). Magma densities depend mostly on composition, iron content being the most important parameter. Magma expands slightly at lower pressure or higher temperature. When magma approaches the surface, its dissolved gases begin to bubble out of the liquid. These bubbles had significantly reduced the density of the magma at depth and helped drive it toward

10465-447: The molecular size. A gas has no definite shape or volume, but occupies the entire container in which it is confined. A liquid may be converted to a gas by heating at constant pressure to the boiling point , or else by reducing the pressure at constant temperature. At temperatures below its critical temperature , a gas is also called a vapor , and can be liquefied by compression alone without cooling. A vapor can exist in equilibrium with

10580-481: The more abundant elements in the source rock. The ions of these elements fit rather poorly in the structure of the minerals making up the source rock, and readily leave the solid minerals to become highly concentrated in melts produced by a low degree of partial melting. Incompatible elements commonly include potassium , barium , caesium , and rubidium , which are large and weakly charged (the large-ion lithophile elements, or LILEs), as well as elements whose ions carry

10695-415: The most abundant chemical elements in the Earth's crust, with smaller quantities of aluminium , calcium , magnesium , iron , sodium , and potassium , and minor amounts of many other elements. Petrologists routinely express the composition of a silicate magma in terms of the weight or molar mass fraction of the oxides of the major elements (other than oxygen) present in the magma. Because many of

10810-471: The net magnetization is zero. For example, in nickel(II) oxide (NiO), half the nickel atoms have moments aligned in one direction and half in the opposite direction. In a ferrimagnet , the two networks of magnetic moments are opposite but unequal, so that cancellation is incomplete and there is a non-zero net magnetization. An example is magnetite (Fe 3 O 4 ), which contains Fe and Fe ions with different magnetic moments. A quantum spin liquid (QSL)

10925-478: The particles cannot move freely but can only vibrate. As a result, a solid has a stable, definite shape, and a definite volume. Solids can only change their shape by an outside force, as when broken or cut. In crystalline solids , the particles (atoms, molecules, or ions) are packed in a regularly ordered, repeating pattern. There are various different crystal structures , and the same substance can have more than one structure (or solid phase). For example, iron has

11040-459: The plasma state. Plasma is by far the most abundant of the four fundamental states, as 99% of all ordinary matter in the universe is plasma, as it composes all stars . A state of matter is also characterized by phase transitions . A phase transition indicates a change in structure and can be recognized by an abrupt change in properties. A distinct state of matter can be defined as any set of states distinguished from any other set of states by

11155-439: The presence of carbon dioxide, experiments document that the peridotite solidus temperature decreases by about 200 °C in a narrow pressure interval at pressures corresponding to a depth of about 70 km. At greater depths, carbon dioxide can have more effect: at depths to about 200 km, the temperatures of initial melting of a carbonated peridotite composition were determined to be 450 °C to 600 °C lower than for

11270-475: The pressure is higher than the triple point of the substance. Intermolecular (or interatomic or interionic) forces are still important, but the molecules have enough energy to move relative to each other and the structure is mobile. This means that the shape of a liquid is not definite but is determined by its container. The volume is usually greater than that of the corresponding solid, the best known exception being water , H 2 O. The highest temperature at which

11385-409: The process of sublimation , and gases can likewise change directly into solids through deposition . A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. The volume is definite if the temperature and pressure are constant. When a solid is heated above its melting point , it becomes liquid, given that

11500-630: The properties of a magma (such as its viscosity and temperature) are observed to correlate with silica content, silicate magmas are divided into four chemical types based on silica content: felsic , intermediate , mafic , and ultramafic . Felsic or silicic magmas have a silica content greater than 63%. They include rhyolite and dacite magmas. With such a high silica content, these magmas are extremely viscous, ranging from 10 cP (10 Pa⋅s) for hot rhyolite magma at 1,200 °C (2,190 °F) to 10 cP (10 Pa⋅s) for cool rhyolite magma at 800 °C (1,470 °F). For comparison, water has

11615-411: The rate of flow is proportional to the shear stress . Instead, a typical magma is a Bingham fluid , which shows considerable resistance to flow until a stress threshold, called the yield stress, is crossed. This results in plug flow of partially crystalline magma. A familiar example of plug flow is toothpaste squeezed out of a toothpaste tube. The toothpaste comes out as a semisolid plug, because shear

11730-405: The roof of a magma chamber and fractional crystallization near its base can even take place simultaneously. Magmas of different compositions can mix with one another. In rare cases, melts can separate into two immiscible melts of contrasting compositions. When rock melts, the liquid is a primary magma . Primary magmas have not undergone any differentiation and represent the starting composition of

11845-405: The same composition with no carbon dioxide. Magmas of rock types such as nephelinite , carbonatite , and kimberlite are among those that may be generated following an influx of carbon dioxide into mantle at depths greater than about 70 km. Increase in temperature is the most typical mechanism for formation of magma within continental crust. Such temperature increases can occur because of

11960-479: The same energy and are thus interchangeable. Degenerate matter is supported by the Pauli exclusion principle , which prevents two fermionic particles from occupying the same quantum state. Unlike regular plasma, degenerate plasma expands little when heated, because there are simply no momentum states left. Consequently, degenerate stars collapse into very high densities. More massive degenerate stars are smaller, because

12075-442: The same lavas ranges over seven orders of magnitude, from 10 cP (10 Pa⋅s) for mafic lava to 10 cP (10 Pa⋅s) for felsic magmas. The viscosity is mostly determined by composition but is also dependent on temperature. The tendency of felsic lava to be cooler than mafic lava increases the viscosity difference. The silicon ion is small and highly charged, and so it has a strong tendency to coordinate with four oxygen ions, which form

12190-451: The same quantum state, but a pair of fermions can behave as a boson, and multiple such pairs can then enter the same quantum state without restriction. Under extremely high pressure, as in the cores of dead stars, ordinary matter undergoes a transition to a series of exotic states of matter collectively known as degenerate matter , which are supported mainly by quantum mechanical effects. In physics, "degenerate" refers to two states that have

12305-404: The source rock. Some calk-alkaline granitoids may be produced by a high degree of partial melting, as much as 15% to 30%. High-magnesium magmas, such as komatiite and picrite , may also be the products of a high degree of partial melting of mantle rock. Certain chemical elements, called incompatible elements , have a combination of ionic radius and ionic charge that is unlike that of

12420-468: The surface and the overburden pressure drops, dissolved gases bubble out of the liquid, so that magma near the surface consists of materials in solid, liquid, and gas phases . Most magma is rich in silica . Rare nonsilicate magma can form by local melting of nonsilicate mineral deposits or by separation of a magma into separate immiscible silicate and nonsilicate liquid phases. Silicate magmas are molten mixtures dominated by oxygen and silicon ,

12535-401: The surface in the first place. The temperature within the interior of the earth is described by the geothermal gradient , which is the rate of temperature change with depth. The geothermal gradient is established by the balance between heating through radioactive decay in the Earth's interior and heat loss from the surface of the earth. The geothermal gradient averages about 25 °C/km in

12650-487: The universe may have passed through these states in the Big Bang . A supersolid is a spatially ordered material (that is, a solid or crystal) with superfluid properties. Similar to a superfluid, a supersolid is able to move without friction but retains a rigid shape. Although a supersolid is a solid, it exhibits so many characteristic properties different from other solids that many argue it is another state of matter. In

12765-624: The upward intrusion of magma from the mantle. Temperatures can also exceed the solidus of a crustal rock in continental crust thickened by compression at a plate boundary . The plate boundary between the Indian and Asian continental masses provides a well-studied example, as the Tibetan Plateau just north of the boundary has crust about 80 kilometers thick, roughly twice the thickness of normal continental crust. Studies of electrical resistivity deduced from magnetotelluric data have detected

12880-467: The upward movement of solid mantle is critical in the evolution of the Earth. Decompression melting creates the ocean crust at mid-ocean ridges , making it by far the most important source of magma on Earth. It also causes volcanism in intraplate regions, such as Europe, Africa and the Pacific sea floor. Intraplate volcanism is attributed to the rise of mantle plumes or to intraplate extension, with

12995-467: The viscosity. Higher-temperature melts are less viscous, since more thermal energy is available to break bonds between oxygen and network formers. Most magmas contain solid crystals of various minerals, fragments of exotic rocks known as xenoliths and fragments of previously solidified magma. The crystal content of most magmas gives them thixotropic and shear thinning properties. In other words, most magmas do not behave like Newtonian fluids, in which

13110-532: The year 2000. Unlike plasma, which flows like a gas, interactions within QGP are strong and it flows like a liquid. At high densities but relatively low temperatures, quarks are theorized to form a quark liquid whose nature is presently unknown. It forms a distinct color-flavor locked (CFL) phase at even higher densities. This phase is superconductive for color charge. These phases may occur in neutron stars but they are presently theoretical. Color-glass condensate

13225-571: Was glaciated , and the most prominent glacial cirques are located on the north and east sides of the range. The range is named after anthracite , a high-quality, metamorphized coal found in the sedimentary rock of the Mesaverde Formation at the base of this and nearby laccoliths. The Anthracite Range is an east-west oriented ridge less than 5 miles (8 km) in length, but there are several summits of interest to mountaineers and peakbaggers. From west to east, these summits include:

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