Draft:Liquids

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Mineral water is being poured from a bottle into a glass. Credit: Walter J. Pilsak.

A liquid is any substance in which its constituent parts stick together but do not crystallize.

The image on the right demonstrates that this substance's constituent parts are sticking together but not crystallizing as it flows from a bottle into a glass.

Theoretical liquids[edit]

Def. any substance having a consistency of flowing freely with a constant volume is called a liquid.

Def. a substance that is flowing, and keeping no shape, a substance of which the molecules, while not tending to separate from one another like those of a gas, readily change their relative position, and which therefore retains no definite shape, except that determined by the containing receptacle is called a liquid.

Metadef.

  1. a flowing substance
  2. keeping or retaining no shape or definite shape
a. except that determined by the containing receptacle
3. composed of molecules or atoms
a. not tending to separate from one another like those of a gas
b. readily changing relative position

is called a liquid.

Clear liquids[edit]

Metadefinition of a clear liquid:

Metadef.

  1. a clear flowing substance
  2. keeping or retaining no shape or definite shape
a. except that determined by the containing receptacle
3. composed of molecules
a. not tending to separate from one another like those of a gas
b. readily changing relative position

is called a clear liquid.

A clear liquid diet consists of transparent liquid foods such as vegetable broth, bouillon, clear fruit juices, clear fruit ices, popsicles, clear gelatin desserts, and no carbonated drinks. Soda's carbonation expands the gastrointestinal tract. Herein are many clear liquids that fit within the metadefinition.

Liquid objects[edit]

Def. any object consisting of at least 2 % by particle, or least divisible particle, number of liquids is called a liquid object.

Mineraloids[edit]

Def. a "substance that resembles a mineral but does not exhibit crystallinity"[1] is called a mineraloid.

Native liquid elements include bromines, galliums and mercuries.

Waters[edit]

Def. a clear liquid having the chemical formula H2O, required by all forms of life on Earth is called water.

Def. of water from the metadefinition of a clear liquid:

  1. a clear flowing substance
  2. keeping or retaining no shape or definite shape
a. except that determined by the containing receptacle
3. composed of H2O molecules
a. not tending to separate from one another like those of a gas
b. readily changing relative position

is called water.

Ethanols[edit]

Def. of ethanol from the metadefinition of a clear liquid:

  1. a clear flowing substance
  2. keeping or retaining no shape or definite shape
a. except that determined by the containing receptacle
3. composed of C2H5OH molecules
a. not tending to separate from one another like those of a gas
b. readily changing relative position

is called ethanol.

Limonites[edit]

Limonite is an amorphous mineraloid of a range of hydrated iron oxides. Credit: USGS.

Limonite is an iron ore consisting of a mixture of hydrated iron(III) oxide-hydroxides in varying composition. The generic formula is frequently written as FeO(OH)·nH2O, although this is not entirely accurate as the ratio of oxide to hydroxide can vary quite widely. Limonite is one of the two principle iron ores, the other being hematite, and has been mined for the production of iron since at least 2500 BCE.[2][3] Although originally defined as a single mineral, limonite is now recognized as a mixture of related hydrated iron oxide minerals, among them goethite, akaganeite, lepidocrocite, and jarosite. Individual minerals in limonite may form crystals, but limonite does not, although specimens may show a fibrous or microcrystalline structure,[4] and limonite often occurs in concretionary forms or in compact and earthy masses; sometimes mammillary, botryoidal, reniform or stalactitic. Because of its amorphous nature, and occurrence in hydrated areas limonite often presents as a clay or mudstone. However there are limonite pseudomorphs after other minerals such as pyrite.[5] This means that chemical weathering transforms the crystals of pyrite into limonite by hydrating the molecules, but the external shape of the pyrite crystal remains. Limonite pseudomorphs have also been formed from other iron oxides, hematite and magnetite; from the carbonate siderite and from iron rich silicates such as almandine garnets. Limonite usually forms from the hydration of hematite and magnetite, from the oxidation and hydration of iron rich sulfide minerals, and chemical weathering of other iron rich minerals such as olivine, pyroxene, amphibole, and biotite. It is often the major iron component in lateritic soils. One of the first uses was as a pigment. The yellow form produced yellow ochre for which Cyprus was famous.[6].

Petroleums[edit]

This is a natural oil (petroleum) seep near Korňa, Kysucké Beskydy, Western Carpathians, Slovakia. Credit: Branork.

Def. a "flammable liquid ranging in color from clear to very dark brown and black, consisting mainly of hydrocarbons, occurring naturally in deposits under the Earth's surface"[7] is called a petroleum.

Coal tars[edit]

The lake tar pit at the La Brea Tar Pits is in Los Angeles, CA, USA. Credit: Buchanan-Hermit.

Def. a "black, oily, sticky, viscous substance, consisting mainly of hydrocarbons derived from organic materials such as wood, peat, or coal"[8] is called a tar.

Def. a thick black liquid produced by the destructive distillation of bituminous coal is called a coal tar.

It contains at least benzene, naphthalene, phenols, and aniline.

Naphthas[edit]

The beaker contains open-specification naphtha from Bangladesh. Credit: Gurumia.com.

Def. any "of a wide variety of aliphatic or aromatic liquid hydrocarbon mixtures distilled from petroleum or coal tar"[9] is called a naphtha.

Malthas[edit]

Def. a black viscid substance intermediate between petroleum and asphalt is called a maltha, or malthite.

Bitumens[edit]

Here, Lussatite, an opal, occurs with bitumen. Credit: Parent Géry.

Def. a black viscous mixture of hydrocarbons obtained naturally is called a bitumen.

In the image on the right, bitumen occurs with lussatite, an opal.

Pitchs[edit]

Pitch Lake (Asphalt Lake) near La Brea on the island of Trinidad in the West Indies is the largest natural Tar or Bitumen Lake in the world. Credit: Richard Seaman.
Mother-of-the-Lake, Pitch Lake, is in Trinidad. Credit: Jw2c.

Def. a "dark, extremely viscous material remaining in still after distilling crude oil and tar"[10] is called a pitch.

Asphalts[edit]

Hand sample including natural asphalt, from Slovakia. Credit: Piotr Gut.

Def. a "sticky, black and highly viscous liquid or semi-solid, composed almost entirely of bitumen, that is present in most crude petroleums and in some natural deposits"[11] is called an asphalt.

Zietrisikites[edit]

Def. a natural, waxy hydrocarbon mineraloid is called a zietrisikite.

Ozocerites[edit]

Ozokerite is from the Brigham Young University Department of Geology, Provo, Utah, collection. Credit: Andrew Silver, USGS.

Def. a natural dark, or black, odoriferous mineraloid wax is called ozokerite, or ozocerite.

Ambers[edit]

These are naturally occurring amber stones. Credit: Lanzi.
This is natural blue dominican amber. Credit: Vassil.

Def. a "hard, generally yellow to brown translucent fossil resin"[12] is called an amber.

Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions.[13] Amber occurring in coal seams is also called resinite, and the term ambrite is applied to that found specifically within New Zealand coal seams.[14]

Amber is a macromolecule by free radical polymerization of several precursors in the labdane family, e.g. communic acid, cummunol, and biformene.[15][16]

Fossil resins from the Americas and Africa are closely related to the modern genus Hymenaea,[17] while Baltic ambers are thought to be fossil resins from the Sciadopityaceae family of plants that used to live in north Europe.[18]

For resin to survive long enough to become amber, it must be resistant to exposure to sunlight, rain, microorganisms (such as bacteria and fungi), and extreme temperatures or be produced under conditions that exclude them.[19]

Sustained heat and pressure drives off terpenes and results in the formation of amber.[20]

Terpenoids, produced by conifers and angiosperms, consist of ring structures formed of isoprene (C5H8) units.[21] Phenolic resins are today only produced by angiosperms. The extinct Medullosales (medullosans) produced a third type of resin, which is often found as amber within their veins.[21] The composition of resins is highly variable; each species produces a unique blend of chemicals which can be identified by the use of pyrolysis–gas chromatography–mass spectrometry.[21] The overall chemical and structural composition is used to divide ambers into five classes.[22][23]

Class I comprises labdatriene carboxylic acids such as communic or ozic acids.[22] Classes Ia and Ib utilize regular labdanoid diterpenes (e.g. communic acid, communol, biformenes), while Ic uses enantio labdanoids (ozic acid, ozol, enantio biformenes).[24]

Class Ia includes Succinite (= 'normal' Baltic amber) and Glessite.[23] They have a communic acid base, and they also include much succinic acid.[22]

Succinic acid may not be an original component of amber, but rather a degradation product of abietic acid.[25]

Like class Ia ambers, Ib are based on communic acid; however, they lack succinic acid.[22]

Ic class is mainly based on enantio-labdatrienonic acids, such as ozic and zanzibaric acids.[22] Its most familiar representative is Dominican amber.[21]

Dominican amber often contains a higher number of fossil inclusions which has enabled the detailed reconstruction of the ecosystem of a long-vanished tropical forest.[26] Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in the tropics. It is not "succinite" but "retinite".[27]

Class II ambers are formed from resins with a sesquiterpenoid base, such as cadinene.[22]

Class III ambers are polystyrenes.[22]

Class IV ambers are not polymerized, but mainly consist of cedrene-based sesquiterpenoids.[22]

Class V resins are considered to be produced by a pine or pine relative. They comprise a mixture of diterpinoid resins and n-alkyl compounds. Their main variety is Copaline (Highgate copalite]).[23]

Hydrogens[edit]

Nuclear device being filled with liquid hydrogen, in preparation for detonation. Credit: Federal government of the United States.
First tracks are observed in liquid hydrogen bubble chamber. Credit: John Wood, 1954.

The image on the right shows that liquid hydrogen can be poured.

The second image down on the right shows a liquid hydrogen bubble chamber used to detect subatomic particles from a bevatron.

Heliums[edit]

The container holds a small amount of liquid helium. Credit: Vuerqex.

Liquid helium as shown on the right is just above absolute zero in temperature.

Nitrogens[edit]

Liquid nitrogen can be poured. Credit: Robin Müller.

On the right liquid nitrogen is shown being poured.

Oxygens[edit]

Liquid oxygen is the liquid in the ampoule that has a pale blue color. Credit: Vimal Cylinder Supplier.

Liquid oxygen as shown on the right may not be perfectly clear.

"Liquid oxygen has a pale blue color and is strongly paramagnetic and can be suspended between the poles of a powerful horseshoe magnet. Liquid oxygen has a density of 1.141 kg/L and is cryogenic. [F]reezing point: 50.5 K (-368.77 °F; -222.65 °C), boiling point: 90.19 K (-297.33 °F, -182.96 °C) at 101.325 kPa (760 mmHg)."[28]

Fluorines[edit]

The center tube contains liquid fluorine. Credit: B. G. Mueller.

Liquid fluorine in the tube on the right is yellow-orange in color.

Sulfurs[edit]

Native liquid sulfur in this photograph is red. Credit: National Iranian Gas Company.

At volcanic locations, native liquid sulfur can be seen flowing, such as in the image on the right, and it is red.

Chlorines[edit]

Liquid chlorine is contained in a flask for analysis. Credit: Workingclass91.
Liquid chlorine is under pressure in an "acrylic glass" (i.e., Plexiglas, Lucite) cube. Credit: Alchemist-hp.

On the right is liquid chlorine (Cl2) contained in a flask for analysis. Liquid chlorine is yellow in color.

Image on the left is an ampoule containing liquid chlorine. It has been liquefied under pressure at >7.4 bar, sealed in the quartz vial (ampoule), further sealed in an "acrylic glass" (i.e., Plexiglas, Lucite) cube, cube edge length: 5 cm.

Argons[edit]

Liquid argon drips off of a small block of solid argon. Credit: Fir0002.

While argon is a gas at room temperature and pressure, it becomes a solid at liquid nitrogen temperature and melts to a liquid as in the image on the right when removed from the liquid nitrogen.

Galliums[edit]

This is a liquid drop of gallium. Credit: RTC.

The second image down on the right is a drop of liquid gallium.

Bromines[edit]

Liquid bromine is contained in a safety jar. Credit: W. Oelen.

Bromine is a halogen that is a liquid at room temperature and pressure.

Indiums[edit]

This photograph shows liquid indium. Credit: Jurii.

Indium has a low melting temperature of 156.6°C.

Mercuries[edit]

The image shows liquid mercury being pour at room temperature and pressure. Credit: Bionerd.

The metallic element mercury is a liquid at room temperature and pressure as shown in the image on the right.

Def. a naturally occurring, silvery-colored, metallic liquid, composed primarily of the chemical element mercury, is called mercury, or native mercury.

Rocks[edit]

Advancing Pahoehoe toe, Kilauea Hawaii 2003, results when Kohola breakouts. Credit: Hawaii Volcano Observatory (DAS).
Many characteristics of a low-viscosity lava flow are visible in this image of Zhupanovsky and Dzenzursky volcanoes on Russia’s Kamchatka Peninsula. Credit: Robert Simmon, NASA Earth Observatory, Landsat 8, the USGS Earth Explorer.
This view of Zhupanovsky shows some of the lava flows. Credit: Игорь Шпиленок.
This Pahoehoe is from Kīlauea in Hawaii. Credit: Tari Noelani Mattox, USGS.
Basalt lava (glowing rock) is oozing over basalt lava flow. Credit: USGS.
Glowing `a`a flow front advances over pahoehoe on the coastal plain of Kilauea Volcano, Hawai`i. Credit: USGS.

Def. "melted rock ejected by a volcano from its crater or fissured sides"[29] is called a lava.

Usage notes

"Geologists make a distinction between magma (molten rock underground) and lava (molten rock on the surface)."[29]

Def. "molten matter within the earth, the source of the material of lava flows, dikes of eruptive rocks, etc"[30] is called a magma.

"Streams of molten rock that ooze from gaps or vents in the Earth’s surface are called lava flows. Though generally slow-moving, these rivers of rock pose a hazard to everything in their paths. They can bury or burn homes and roads, ruin farmland for generations, and transform glaciers into muddy landslides (lahars)."[31]

"Lava flows can take many shapes and move at very different rates depending on the viscosity of the magma, the slope of the land, and the rate of an eruption. Some of the speediest flows travel 60 kilometers (40 miles) per hour; the slowest creep along at less than 1 kilometer (0.6 miles) per hour. They can sometimes even flow for more than a year after an eruption has ended."[31]

"While viscous lava flows are defined by steep flow fronts and pressure ridges, low-viscosity lavas tend to move faster and create longer, narrower shapes. They also tend to have smaller flow fronts and levee-like structure along their edges. Many characteristics of a low-viscosity lava flow are visible in [the image on the right second down] of Zhupanovsky and Dzenzursky volcanoes on Russia’s Kamchatka Peninsula. The image was acquired by the Operational Land Imager (OLI) on the Landsat 8 satellite on September 9, 2013."[32]

"In the image, younger lava flows appear grey, while older flows are covered by green vegetation. The exact ages of the flows are unclear, but the eruptions that produced them likely occurred during the past few thousand years. Distinctive lava levees are visible along the edges of many of the younger flows. These features form as lava cools and hardens along the edges or top of a flow while the center of a flow still advances."[32]

"In comparison to the Chao dacite in Chile (the product of viscous lava), the flows at Zhupanovsky [at lowest right] and Dzenzursky are much narrower and longer. They have smaller flow fronts (10 to 30 meters tall) in comparison to the sheer 400-meter cliffs at Chao, as well as more prominent lava levees along the edges. Like Chao, the flows shown above have pressure ridges caused by the compression of the cooling top of the lava as the flow advanced."[32]

Def. a "form of lava flow of basaltic rock, usually dark-colored with a smooth or ropey surface"[33] is called pahoehoe.

"Ropy pahoehoe [shown in the fourth image down on the right, taken 11 June 1995] is the most common surface texture of pahoehoe flows. The numerous folds and wrinkles ("ropes") that are characteristic of ropy pahoehoe form when the thin, partially solidified crust of a flow is slowed or halted (for example, if the crust encounters an obstruction or slower-moving crust). Because lava beneath the crust continues to move forward, it tends to drag the crust along. The crust then behaves like an accordian that is squeezed together--the crust is flexible enough to develop wrinkles or a series of small ridges and troughs as it is compressed and driven forward."[34]

Def. a "form of lava flow [associated with Hawaiian-type volcanoes, consisting][35] of basaltic rock, usually dark-colored with a jagged and loose, clinkery surface"[36] is called an aa (fifth image down on the right).

"`A`a (pronounced "ah-ah") is a Hawaiian term for lava flows that have a rough rubbly surface composed of broken lava blocks called clinkers. The incredibly spiny surface of a solidified `a`a flow makes walking very difficult and slow. The clinkery surface actually covers a massive dense core, which is the most active part of the flow. As pasty lava in the core travels downslope, the clinkers are carried along at the surface. At the leading edge of an `a`a flow, however, these cooled fragments tumble down the steep front and are buried by the advancing flow. This produces a layer of lava fragments both at the bottom and top of an `a`a flow."[37]

Obsidians[edit]

This is a specimen of obsidian from Lake County, Oregon. Credit: Locutus Borg.

An example of obsidian is shown on the right. Obsidian is a naturally occurring glass. Glass is an extremely viscous liquid.

Def. a naturally occurring black glass is called an obsidian.

Tektites[edit]

Def. "[a] small, round, dark glassy object, composed of silicates"[38] is called a tektite.

Opals[edit]

Def. a naturally occurring, hydrous, amorphous form of silica, where 3% to 21% of the total weight is water is called an opal.

Craters[edit]

Impact from a water drop to water causes an upward "rebound" jet surrounded by circular capillary waves. Credit: Fir0002/Flagstaffotos.

In the image on the right impact from a water drop to contained but open water causes an upward "rebound" jet surrounded by circular capillary waves.

Technology[edit]

The largest single use of liquid helium is to cool the superconducting magnets in modern MRI scanners. Credit: .





Circle frame.svg

Estimated 2013 U.S. fractional helium use by category. Total use is 47 million cubic meters.[39]

  Cryogenics (32%)
  Pressurizing and purging (18%)
  Welding (13%)
  Controlled atmospheres (18%)
  Leak detection (4%)
  Breathing mixtures (2%)
  Other (13%)

Hypotheses[edit]

  1. Many liquids exist within specific ranges of temperature and pressure.

See also[edit]

References[edit]

  1. mineraloid. San Francisco, California: Wikimedia Foundation, Inc. 20 April 2011. Retrieved 23 October 2012.
  2. MacEachern, Scott (1996) "Iron Age beginnings north of the Mandara Mountains, Cameroon and Nigeria" pp. 489–496 In Pwiti, Gilbert and Soper, Robert (editors) (1996) Aspects of African Archaeology: Proceedings of the Tenth Pan-African Congress University of Zimbabwe Press, Harare, Zimbabwe, ISBN 978-0-908307-55-5; archived here by Internet Archive on 11 March 2012
  3. Diop-Maes, Louise Marie (1996) "La question de l'Âge du fer en Afrique" ("The question of the Iron Age in Africa") Ankh 4/5: pp. 278–303, in French; archived here by Internet Archive on 25 January 2008
  4. Boswell, P. F. and Blanchard, Roland (1929) "Cellular structure in limonite" Economic Geology 24(8): pp. 791–796
  5. Northrop, Stuart A. (1959) "Limonite" Minerals of New Mexico (revised edition) University of New Mexico Press, Albuquerque, New Mexico, pp. 329–333 }}
  6. Constantinou, G. and Govett, G. J. S. (1972) "Genesis of sulphide deposits, ochre and umber of Cyprus" Transactions of the Institution of Mining and Metallurgy" 81: pp. 34–46
  7. petroleum. San Francisco, California: Wikimedia Foundation, Inc. 16 July 2014. Retrieved 9 January 2015.
  8. tar. San Francisco, California: Wikimedia Foundation, Inc. 5 January 2015. Retrieved 9 January 2015.
  9. naphtha. San Francisco, California: Wikimedia Foundation, Inc. 16 December 2014. Retrieved 9 January 2015.
  10. pitch. San Francisco, California: Wikimedia Foundation, Inc. 12 December 2014. Retrieved 10 January 2015.
  11. asphalt. San Francisco, California: Wikimedia Foundation, Inc. 20 October 2014. Retrieved 9 January 2015.
  12. amber. San Francisco, California: Wikimedia Foundation, Inc. 19 December 2014. Retrieved 9 January 2015.
  13. St. Fleur, Nicholas (8 December 2016). That Thing With Feathers Trapped in Amber? It Was a Dinosaur Tail, In: The New York Times. Retrieved 8 December 2016.
  14. Poinar GO, Poinar R. (1995) The quest for life in amber. Basic Books, ISBN 0-201-48928-7, p. 133
  15. Rudler, Frederick William. Amber (resin). 1. pp. 792–794.
  16. Manuel Villanueva-García, Antonio Martínez-Richa, and Juvencio Robles "Assignment of vibrational spectra of labdatriene derivatives and ambers: A combined experimental and density functional theoretical study" [1] 12 April 2006 pages 449–458
  17. Lambert, JB; Poinar Jr, GO (2002). "Amber: the organic gemstone". Accounts of Chemical Research 35 (8): 628–36. doi:10.1021/ar0001970. PMID 12186567. 
  18. Wolfe, A. P.; Tappert, R.; Muehlenbachs, K.; Boudreau, M.; McKellar, R. C.; Basinger, J. F.; Garrett, A. (30 June 2009). "A new proposal concerning the botanical origin of Baltic amber". Proceedings of the Royal Society B: Biological Sciences 276 (1672): 3403–3412. doi:10.1098/rspb.2009.0806. PMID 19570786. PMC 2817186. https://web.archive.org/web/20160304090529/http://rspb.royalsocietypublishing.org/content/276/1672/3403.full. 
  19. Poinar, George O. (1992) Life in amber. Stanford, Calif.: Stanford University Press, p. 12, ISBN 0804720010
  20. Rice, Patty C. (2006). Amber: Golden Gem of the Ages. 4th Ed. AuthorHouse. ISBN 1-4259-3849-3.
  21. 21.0 21.1 21.2 21.3 Grimaldi, D. (2009). "Pushing Back Amber Production". Science 326 (5949): 51–2. doi:10.1126/science.1179328. PMID 19797645. 
  22. 22.0 22.1 22.2 22.3 22.4 22.5 22.6 22.7 Anderson, K; Winans, R; Botto, R (1992). "The nature and fate of natural resins in the geosphere—II. Identification, classification and nomenclature of resinites". Organic Geochemistry 18 (6): 829–841. doi:10.1016/0146-6380(92)90051-X. 
  23. 23.0 23.1 23.2 Anderson, K; Botto, R (1993). "The nature and fate of natural resins in the geosphere—III. Re-evaluation of the structure and composition of Highgate Copalite and Glessite". Organic Geochemistry 20 (7): 1027. doi:10.1016/0146-6380(93)90111-N. 
  24. Anderson, Ken B. (1996). Amber, Resinite, and Fossil, In: New Evidence Concerning the Structure, Composition, and Maturation of Class I (Polylabdanoid) Resinites Resins. 617. pp. 105–129. doi:10.1021/bk-1995-0617.ch006. ISBN 0-8412-3336-5.
  25. Shashoua, Yvonne (2007). Degradation and inhibitive conservation of Baltic amber in museum collections (PDF). Retrieved 11 May 2011.
  26. George Poinar, Jr. and Roberta Poinar, 1999. The Amber Forest: A Reconstruction of a Vanished World, (Princeton University Press) ISBN 0-691-02888-5
  27. Grimaldi, D. A. (1996) Amber – Window to the Past. – American Museum of Natural History, New York, ISBN 0810919664
  28. Vimal Cylinder Supplier (2014). Our Products : Liquid Oxygen. 30, Shilpi Appartment, 5th Floor, Kalanala, Bhavnagar-2, Gujarat: Vimal Cylinder Supplier. Retrieved 12 March 2016.
  29. 29.0 29.1 lava. San Francisco, California: Wikimedia Foundation, Inc. 25 January 2011. Retrieved 17 February 2015.
  30. magma. San Francisco, California: Wikimedia Foundation, Inc. 29 December 2014. Retrieved 17 February 2015.
  31. 31.0 31.1 Erik Klemetti and Adam Voiland (21 November 2013). The Shapes that Lavas Take, Part 1. Washington, DC USA: NASA. Retrieved 18 February 2015.
  32. 32.0 32.1 32.2 Erik Klemetti and Adam Voiland (22 November 2013). The Shapes that Lavas Take, Part 2. Washington, DC USA: NASA. Retrieved 18 February 2015.
  33. pahoehoe. San Francisco, California: Wikimedia Foundation, Inc. 31 July 2014. Retrieved 18 February 2015.
  34. Tari Noelani Mattox (4 September 2000). Photo glossary of volcano terms. Menlo Park, California, USA: U.S. Geological Survey. Retrieved 18 February 2015.
  35. Widsith (16 September 2007). aa. San Francisco, California: Wikimedia Foundation, Inc. Retrieved 8 February 2018.
  36. Marshman~enwiktionary (11 May 2005). aa. San Francisco, California: Wikimedia Foundation, Inc. Retrieved 8 February 2018.
  37. United States Geological Survey (17 July 2008). VHP Photo Glossary: AA. Menlo Park, California USA: USGS. Retrieved 10 March 2015.
  38. tektite. San Francisco, California: Wikimedia Foundation, Inc. 31 August 2012. Retrieved 23 October 2012.
  39. U.S. Department of the Interior, U.S. Geological Survey (2014). "Helium" (PDF). Mineral Commodity Summaries 2014. pp. 72–73.

External links[edit]

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