Editing Basalt (section)

== Distribution ==

===Earth===
Basalt is the most common volcanic rock type on Earth, making up over 90% of all volcanic rock on the planet.<ref name="UnivAuckland">{{cite web | url=https://flexiblelearning.auckland.ac.nz/rocks_minerals/rocks/basalt.html | title=Basalt | publisher=The University of Auckland | website=Geology: rocks and minerals | date=2005 | access-date=27 July 2018}}</ref> The [[crust (geology)|crustal]] portions of [[ocean]]ic [[tectonic plate]]s are composed predominantly of basalt, produced from upwelling mantle below the [[ocean ridge]]s.{{sfn|Philpotts|Ague|2009|pp=366–368}} Basalt is also the principal volcanic rock in many [[oceanic island]]s, including the islands of [[Hawaii (island)|Hawai{{okina}}i]],{{sfn|Philpotts|Ague|2009|pp=365–370}} the [[Faroe Islands]],{{sfn|Schmincke|2003|p=91}} and [[Réunion]].<ref name="upton-wadsworth-1965">{{cite journal |last1=Upton |first1=B. G. J. |last2=Wadsworth |first2=W. J. |title=Geology of Réunion Island, Indian Ocean |journal=Nature |date=July 1965 |volume=207 |issue=4993 |pages=151–154 |doi=10.1038/207151a0 |bibcode=1965Natur.207..151U |s2cid=4144134 }}</ref> The eruption of basalt lava is observed by geologists at about 20 volcanoes per year.<ref name="Walker1993">{{Cite book |last1=Walker |first1=G.P.L. |chapter=Basaltic-volcano systems |editor1-last=Prichard |editor1-first=H.M. |editor2-last=Alabaster |editor2-first=T.  |editor3-last=Harris |editor3-first=N.B.W. |editor4-last=Neary |editor4-first=C.R. |title=Magmatic Processes and Plate Tectonics |pages=3–38 |publisher=The Geological Society |series=Geological Society Special Publication 76 |date=1993 |isbn=978-0-903317-94-8 }}</ref>

[[File:Parana traps.JPG|thumb|[[Paraná Traps]], [[Brazil]]]]
Basalt is the rock most typical of [[large igneous province]]s. These include [[continental flood basalt]]s, the most voluminous basalts found on land.{{sfn|Philpotts|Ague|2009|pp=52–59}} Examples of continental flood basalts included the [[Deccan Traps]] in [[India]],<ref>{{cite book |doi=10.1007/978-94-015-7805-9_5 |chapter=Deccan Traps |title=Continental Flood Basalts |series=Petrology and Structural Geology |year=1988 |last1=Mahoney |first1=John J. |volume=3 |pages=151–194 |isbn=978-90-481-8458-3 }}</ref> the [[Chilcotin Group]] in [[British Columbia]],<ref>{{cite journal |last1=Bevier |first1=Mary Lou |title=Regional stratigraphy and age of Chilcotin Group basalts, south-central British Columbia |journal=Canadian Journal of Earth Sciences |date=1 April 1983 |volume=20 |issue=4 |pages=515–524 |doi=10.1139/e83-049|bibcode=1983CaJES..20..515B }}</ref> [[Canada]], the [[Paraná Traps]] in Brazil,<ref>{{cite journal |last1=Renne |first1=P. R. |last2=Ernesto |first2=M. |last3=Pacca |first3=I. G. |last4=Coe |first4=R. S. |last5=Glen |first5=J. M. |last6=Prevot |first6=M. |last7=Perrin |first7=M. |title=The Age of Parana Flood Volcanism, Rifting of Gondwanaland, and the Jurassic-Cretaceous Boundary |journal=Science |date=6 November 1992 |volume=258 |issue=5084 |pages=975–979 |doi=10.1126/science.258.5084.975|pmid=17794593 |bibcode=1992Sci...258..975R |s2cid=43246541 }}</ref> the [[Siberian Traps]] in [[Russia]],<ref>{{cite journal |last1=Renne |first1=P. R. |last2=Basu |first2=A. R. |title=Rapid Eruption of the Siberian Traps Flood Basalts at the Permo-Triassic Boundary |journal=Science |date=12 July 1991 |volume=253 |issue=5016 |pages=176–179 |doi=10.1126/science.253.5016.176 |pmid=17779134 |bibcode=1991Sci...253..176R |s2cid=6374682 }}</ref> the [[Karoo]] [[flood basalt]] province in South Africa,<ref>{{cite journal |last1=Jourdan |first1=F. |last2=Féraud |first2=G. |last3=Bertrand |first3=H. |last4=Watkeys |first4=M. K. |title=From flood basalts to the inception of oceanization: Example from the 40 Ar/ 39 Ar high-resolution picture of the Karoo large igneous province |journal=Geochemistry, Geophysics, Geosystems |date=February 2007 |volume=8 |issue=2 |pages=n/a |doi=10.1029/2006GC001392 |bibcode=2007GGG.....8.2002J |doi-access=free }}</ref> and the [[Columbia River Plateau]] of [[Washington (state)|Washington]] and [[Oregon]].<ref>{{cite journal |last1=Hooper |first1=P. R. |title=The Columbia River Basalts |journal=Science |date=19 March 1982 |volume=215 |issue=4539 |pages=1463–1468 |doi=10.1126/science.215.4539.1463 |pmid=17788655 |bibcode=1982Sci...215.1463H |s2cid=6182619 }}</ref> Basalt is also prevalent across extensive regions of the Eastern [[Galilee earthquake of 1837|Galilee]], [[Golan Heights|Golan]], and [[Bashan]] in [[Israel]] and [[Syria]].<ref>{{Cite book |last1=Reich |first1=Ronny |title=The Architecture of Ancient Israel |last2=Katzenstein |first2=Hannah |date=1992 |publisher=Israel Exploration Society |isbn=978-965-221-013-5 |editor-last=Kempinski |editor-first=Aharon |location=Jerusalem |pages=312 |chapter=Glossary of Archaeological Terms |editor-last2=Reich |editor-first2=Ronny }}</ref>

Basalt also is common around volcanic arcs, specially those on thin [[crust (geology)|crust]].{{sfn|Philpotts|Ague|2009|pp=374-380}}

Ancient [[Precambrian]] basalts are usually only found in fold and thrust belts, and are often heavily metamorphosed. These are known as [[greenstone belt]]s,{{sfn|Philpotts|Ague|2009|pp=398–399}}<ref>{{cite journal |last1=Smithies |first1=R. Hugh |last2=Ivanic |first2=Tim J. |last3=Lowrey |first3=Jack R. |last4=Morris |first4=Paul A. |last5=Barnes |first5=Stephen J. |last6=Wyche |first6=Stephen |last7=Lu |first7=Yong-Jun |title=Two distinct origins for Archean greenstone belts |journal=Earth and Planetary Science Letters |date=April 2018 |volume=487 |pages=106–116 |doi=10.1016/j.epsl.2018.01.034 |bibcode=2018E&PSL.487..106S }}</ref> because low-grade [[metamorphism]] of basalt produces [[Chlorite group|chlorite]], [[actinolite]], [[epidote]] and other green minerals.{{sfn|Blatt|Tracy|1996|pp=366-367}}

===Other bodies in the Solar System===
As well as forming large parts of the Earth's crust, basalt also occurs in other parts of the Solar System. Basalt commonly erupts on [[Io (moon)|Io]] (the third largest moon of [[Jupiter]]),<ref name="LopesGregg">{{cite book | title=Volcanic Worlds: Exploring The Solar System's Volcanoes | publisher=Springer-Praxis | last1=Lopes | first1=Rosaly M. C. | author1-link=Rosaly Lopes | last2=Gregg | first2=Tracy K. P. | year=2004 | page=135 | isbn=978-3-540-00431-8}}</ref> and has also formed on the [[Moon]], [[Mars]], [[Venus]], and the asteroid [[4 Vesta|Vesta]].

====The Moon====
[[File:Lunar Olivine Basalt 15555 from Apollo 15 in National Museum of Natural History.jpg|thumb|Lunar [[olivine]] basalt collected by [[Apollo 15]] astronauts]]
The dark areas visible on Earth's [[moon]], the [[lunar mare|lunar maria]], are plains of [[flood basalt]]ic lava flows. These rocks were sampled both by the crewed American [[Apollo program]] and the robotic Russian [[Luna program]], and are represented among the [[lunar meteorite]]s.<ref name="lucey-2006">{{cite journal |last1=Lucey |first1=P. |title=Understanding the Lunar Surface and Space-Moon Interactions |journal=Reviews in Mineralogy and Geochemistry |date=1 January 2006 |volume=60 |issue=1 |pages=83–219 |doi=10.2138/rmg.2006.60.2|bibcode=2006RvMG...60...83L }}</ref>

Lunar basalts differ from their Earth counterparts principally in their high iron contents, which typically range from about 17 to 22 wt% FeO. They also possess a wide range of titanium concentrations (present in the mineral [[ilmenite]]),<ref name="NYT-20151228">{{cite news |last=Bhanoo |first=Sindya N. |title=New Type of Rock Is Discovered on Moon |url=https://www.nytimes.com/2015/12/29/science/new-type-of-rock-is-discovered-on-moon.html |date=28 December 2015 |work=[[The New York Times]] |access-date=29 December 2015 }}</ref><ref>{{cite journal |last1=Ling |first1=Zongcheng |last2=Jolliff |first2=Bradley L. |last3=Wang |first3=Alian |last4=Li |first4=Chunlai |last5=Liu |first5=Jianzhong |last6=Zhang |first6=Jiang |last7=Li |first7=Bo |last8=Sun |first8=Lingzhi |last9=Chen |first9=Jian |last10=Xiao |first10=Long |last11=Liu |first11=Jianjun |last12=Ren |first12=Xin |last13=Peng |first13=Wenxi |last14=Wang |first14=Huanyu |last15=Cui |first15=Xingzhu |last16=He |first16=Zhiping |last17=Wang |first17=Jianyu |title=Correlated compositional and mineralogical investigations at the Chang'e-3 landing site |journal=Nature Communications |date=December 2015 |volume=6 |issue=1 |pages=8880 |doi=10.1038/ncomms9880 |pmid=26694712 |pmc=4703877 |bibcode=2015NatCo...6.8880L |doi-access=free }}</ref> ranging from less than 1 wt% TiO<sub>2</sub>, to about 13 wt.%. Traditionally, lunar basalts have been classified according to their titanium content, with classes being named high-Ti, low-Ti, and very-low-Ti. Nevertheless, global geochemical maps of titanium obtained from the [[Clementine mission]] demonstrate that the lunar maria possess a continuum of titanium concentrations, and that the highest concentrations are the least abundant.<ref name="GiguereEtAl2000">{{cite journal |last1=Giguere |first1=Thomas A. |last2=Taylor |first2=G. Jeffrey |last3=Hawke |first3=B. Ray |last4=Lucey |first4=Paul G. |title=The titanium contents of lunar mare basalts |journal=Meteoritics & Planetary Science |date=January 2000 |volume=35 |issue=1 |pages=193–200 |doi=10.1111/j.1945-5100.2000.tb01985.x |bibcode=2000M&PS...35..193G |doi-access=free }}</ref>

Lunar basalts show exotic textures and mineralogy, particularly [[shock metamorphism]], lack of the [[redox|oxidation]] typical of terrestrial basalts, and a complete lack of [[mineral hydration|hydration]].{{sfn|Lucey|2006}} Most of the [[geology of the Moon|Moon]]'s basalts erupted between about 3 and 3.5 billion years ago, but the oldest samples are 4.2 billion years old, and the youngest flows, based on the age dating method of [[crater counting]], are estimated to have erupted only 1.2 billion years ago.<ref name="hiesinger-etal-200">{{cite journal |last1=Hiesinger |first1=Harald |last2=Jaumann |first2=Ralf |last3=Neukum |first3=Gerhard |last4=Head |first4=James W. |title=Ages of mare basalts on the lunar nearside |journal=Journal of Geophysical Research: Planets |date=25 December 2000 |volume=105 |issue=E12 |pages=29239–29275 |doi=10.1029/2000JE001244 |bibcode=2000JGR...10529239H |doi-access=free }}</ref>

====Venus====
From 1972 to 1985, five [[Venera]] and two [[Vega program|VEGA]] landers successfully reached the surface of Venus and carried out geochemical measurements using X-ray fluorescence and gamma-ray analysis. These returned results consistent with the rock at the landing sites being basalts, including both tholeiitic and highly alkaline basalts. The landers are thought to have landed on plains whose radar signature is that of basaltic lava flows. These constitute about 80% of the surface of Venus. Some locations show high reflectivity consistent with unweathered basalt, indicating basaltic volcanism within the last 2.5 million years.<ref name="gilmore-etal-2017">{{cite journal |last1=Gilmore |first1=Martha |last2=Treiman |first2=Allan |last3=Helbert |first3=Jörn |last4=Smrekar |first4=Suzanne |title=Venus Surface Composition Constrained by Observation and Experiment |journal=Space Science Reviews |date=November 2017 |volume=212 |issue=3–4 |pages=1511–1540 |doi=10.1007/s11214-017-0370-8|bibcode=2017SSRv..212.1511G |s2cid=126225959 }}</ref>

====Mars====
Basalt is also a common rock on the surface of [[Mars]], as determined by data sent back from the planet's surface,<ref name="grotzinger-2013">{{cite journal|last1=Grotzinger|first1=J. P.|title=Analysis of Surface Materials by the Curiosity Mars Rover|journal=Science|date=26 September 2013|volume=341|issue=6153|pages=1475|doi=10.1126/science.1244258|pmid=24072916|bibcode=2013Sci...341.1475G|doi-access=free}}</ref> and by [[Martian meteorite]]s.<ref>{{Cite web  |last1=Choi |first1=Charles Q. |date=11 October 2012| url=http://www.space.com/18014-mars-meteorites-black-glass.html | title=Meteorite's Black Glass May Reveal Secrets of Mars |website=Space.com | publisher=Future US, Inc. |access-date=24 March 2021}}</ref><ref>{{cite journal |last1=Gattacceca |first1=Jérôme |last2=Hewins |first2=Roger H. |last3=Lorand |first3=Jean-Pierre |last4=Rochette |first4=Pierre |last5=Lagroix |first5=France |last6=Cournède |first6=Cécile |last7=Uehara |first7=Minoru |last8=Pont |first8=Sylvain |last9=Sautter |first9=Violaine |author9-link=Violaine Sautter|last10=Scorzelli |first10=Rosa. B. |last11=Hombourger |first11=Chrystel |last12=Munayco |first12=Pablo |last13=Zanda |first13=Brigitte |last14=Chennaoui |first14=Hasnaa |last15=Ferrière |first15=Ludovic |title=Opaque minerals, magnetic properties, and paleomagnetism of the Tissint Martian meteorite |journal=Meteoritics & Planetary Science |date=October 2013 |volume=48 |issue=10 |pages=1919–1936 |doi=10.1111/maps.12172|bibcode=2013M&PS...48.1919G |doi-access=free }}</ref>

====Vesta====
Analysis of [[Hubble Space Telescope]] images of Vesta suggests this [[asteroid]] has a basaltic crust covered with a brecciated [[regolith]] derived from the crust.<ref name="binzel-etal-1997">{{cite journal |last1=Binzel |first1=Richard P |last2=Gaffey |first2=Michael J |last3=Thomas |first3=Peter C |last4=Zellner |first4=Benjamin H |last5=Storrs |first5=Alex D |last6=Wells |first6=Eddie N |title=Geologic Mapping of Vesta from 1994 Hubble Space Telescope Images |journal=Icarus |date=July 1997 |volume=128 |issue=1 |pages=95–103 |doi=10.1006/icar.1997.5734|bibcode=1997Icar..128...95B |doi-access=free }}</ref> Evidence from Earth-based telescopes and the [[Dawn (spacecraft)|Dawn mission]] suggest that Vesta is the source of the [[HED meteorite]]s, which have basaltic characteristics.<ref name="mittlefehldt-2015">{{cite journal |last1=Mittlefehldt |first1=David W. |title=Asteroid (4) Vesta: I. The howardite-eucrite-diogenite (HED) clan of meteorites |journal=Geochemistry |date=June 2015 |volume=75 |issue=2 |pages=155–183 |doi=10.1016/j.chemer.2014.08.002 |bibcode=2015ChEG...75..155M }}</ref> Vesta is the main contributor to the inventory of basaltic asteroids of the main Asteroid Belt.<ref>{{cite journal |last1=Moskovitz |first1=Nicholas A. |last2=Jedicke |first2=Robert |last3=Gaidos |first3=Eric |last4=Willman |first4=Mark |last5=Nesvorný |first5=David |last6=Fevig |first6=Ronald |last7=Ivezić |first7=Željko |title=The distribution of basaltic asteroids in the Main Belt |journal=Icarus |date=November 2008 |volume=198 |issue=1 |pages=77–90 |doi=10.1016/j.icarus.2008.07.006 |arxiv=0807.3951 |bibcode=2008Icar..198...77M |s2cid=38925782 }}</ref>

====Io====
Lava flows represent a major volcanic terrain on [[Io (moon)|Io]].<ref name="Keszthelyi2001">{{cite journal |last1=Keszthelyi |first1=L. |last2=McEwen |first2=A. S. |last3=Phillips |first3=C. B.|author3-link=Cynthia B. Phillips |last4=Milazzo |first4=M. |last5=Geissler |first5=P. |last6=Turtle |first6=E. P. |last7=Radebaugh |first7=J. |last8=Williams |first8=D. A. |last9=Simonelli |first9=D. P. |last10=Breneman |first10=H. H. |last11=Klaasen |first11=K. P. |last12=Levanas |first12=G. |last13=Denk |first13=T. |title=Imaging of volcanic activity on Jupiter's moon Io by Galileo during the Galileo Europa Mission and the Galileo Millennium Mission |journal=Journal of Geophysical Research: Planets |date=2001-12-25 |volume=106 |issue=E12 |pages=33025–33052 |doi=10.1029/2000JE001383 |bibcode=2001JGR...10633025K |doi-access=free }}</ref> Analysis of the ''Voyager'' images led scientists to believe that these flows were composed mostly of various compounds of molten sulfur. However, subsequent Earth-based [[infrared]] studies and measurements from the ''Galileo'' spacecraft indicate that these flows are composed of basaltic lava with mafic to ultramafic compositions.<ref name="Battaglia2019">{{Cite conference |title= A Jökulhlaup-like Model for Secondary Sulfur Flows on Io |conference=50th Lunar and Planetary Science Conference. 18–22 March 2019. The Woodlands, Texas. |first=Steven M. |last=Battaglia |date=March 2019 |id=LPI Contribution No. 1189 |url=https://www.hou.usra.edu/meetings/lpsc2019/pdf/1189.pdf | bibcode=2019LPI....50.1189B}}</ref> This conclusion is based on temperature measurements of Io's "hotspots", or thermal-emission locations, which suggest temperatures of at least 1,300&nbsp;K and some as high as 1,600&nbsp;K.<ref name="Keszthelyi2007">{{cite journal |last1=Keszthelyi |first1=Laszlo |last2=Jaeger |first2=Windy |last3=Milazzo |first3=Moses |last4=Radebaugh |first4=Jani |last5=Davies |first5=Ashley Gerard |last6=Mitchell |first6=Karl L. |title=New estimates for Io eruption temperatures: Implications for the interior |journal=Icarus |date=December 2007 |volume=192 |issue=2 |pages=491–502 |doi=10.1016/j.icarus.2007.07.008 |bibcode=2007Icar..192..491K |url=https://zenodo.org/record/1259031 }}</ref> Initial estimates suggesting eruption temperatures approaching 2,000&nbsp;K<ref name="Mcewen1998b">{{cite journal |title=High-temperature silicate volcanism on Jupiter's moon Io |journal=Science |last=McEwen |first=A. S. |display-authors=etal |pages=87–90 |volume=281 |issue=5373 |date=1998 |doi=10.1126/science.281.5373.87 |pmid=9651251 |bibcode=1998Sci...281...87M |s2cid=28222050 }}</ref> have since proven to be overestimates because the wrong thermal models were used to model the temperatures.<ref name="Keszthelyi2007"/>{{sfn|Battaglia|2019}}