Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Impactite
open-in-new
<h2 id="creation">Creation</h2> <p>When a large meteorite hits a planet, it can radically deform the rocks and <a href="/facts/Regolith/EdXuHK56">regolith</a> that it hits. The heat, pressure, and shock of the impact changes these materials into impactite.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> Only very massive impacts generate the heat and pressure needed to transform a rock, so impactites are created rarely.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h2 id="characteristics">Characteristics</h2> <p>Impactite includes <a href="/facts/Shock_metamorphism/5X0Ub069">shock-metamorphosed</a> target rocks, melts (<a href="/facts/Suevite/LUFc5Yz4">suevites</a>) and mixtures of the two, as well as sedimentary rocks with significant impact-derived components (shocked mineral grains, <a href="/facts/Tektites/XRpHJSdX">tektites</a>, anomalous geochemical signatures, etc.). In June 2015, NASA reported that impact glass has been detected on the planet <a href="/facts/Mars/AQGtVvz0">Mars</a>. Such material may contain preserved signs of <a href="/facts/Life_on_Mars/A14ye2It">ancient life</a>—if life existed.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> Impactites are generally classified into three groups: shocked rocks, impact melt, and impact breccias.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> </p> <h3>Shocked rock</h3> <p>Shocked rocks have been transformed by <a href="/facts/Shock_metamorphism/5X0Ub069">shock metamorphism</a> caused by the impact. They include <a href="/facts/Shatter_cone/gIYIPGay">shatter cones</a> and high-pressure minerals, for example <a href="/facts/Coesite/uQEYMrnD">coesite</a> and <a href="/facts/Stishovite/WB6d8SKS">stishovite</a>. </p> <h3>Impact melts</h3> <p>When a meteor strikes a planet's surface, the energy released from the impact can melt rock and soil into a liquid. The liquid then cools and becomes an impact melt.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> If the liquid cools and hardens quickly into a solid, impact glass forms before the atoms have time to arrange into a <a href="/facts/Crystal_lattice/7gQKTsXk">crystal lattice</a>. Impact glass can be dark brown, almost black, and partly transparent.<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> Sometimes, the cooled liquid does form a crystal structure. In that case, it would still be considered an impact melt, but not an impact glass.<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> </p> <h3>Impact breccias</h3> <p><a href="/facts/Breccia/fEmNFy8W">Breccia</a> is "a rock consisting of angular fragments cemented together".<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> An impact breccia is formed when a meteor shatters a rock and then cements it back together. Some breccias contain impact melts.<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> </p> <h2 id="examples-of-impactite">Examples of impactite</h2> <p>Impactite has been found, for example, at the following impact craters and structures: </p> <ul><li><a href="/facts/Alamo_bolide_impact/26N5VomY">Alamo bolide impact</a> (Late Devonian), Nevada, United States</li> <li><a href="/facts/List_of_craters_on_Mars:_A-G/yJp12GKF">Alga crater</a> on the planet <a href="/facts/Mars/AQGtVvz0">Mars</a><a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a></li> <li><a href="/facts/Barringer_crater/J3KyXJ8w">Barringer crater</a>, Arizona, United States<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a></li> <li><a href="/facts/Charlevoix_impact_structure/FHRGfIEW">Charlevoix impact structure</a>, Québec, Canada</li> <li><a href="/facts/Darwin_Crater/uCfNIYqF">Darwin Crater</a>, Tasmania (source of <a href="/facts/Darwin_glass/sAUBRG8v">Darwin glass</a>)</li> <li><a href="/facts/Lake_Lappaj%C3%A4rvi/uRHu9L3E">Lake Lappajärvi</a>, Finland (source of <a href="/facts/K%C3%A4rn%C3%A4ite/uRHu9L3E">Kärnäite</a>)</li> <li><a href="/facts/Manicouagan_Reservoir/hJm4VYYT">Manicouagan impact structure</a>, Québec, Canada</li> <li><a href="/facts/Neugrund_crater/BfRwkBQG">Neugrund crater</a>, Estonia</li> <li><a href="/facts/N%C3%B6rdlinger_Ries/7hcG9bKj">Nördlinger Ries</a> crater, Germany</li> <li><a href="/facts/Rochechouart_impact_structure/Qob8SuMR">Rochechouart impact structure</a>, France</li> <li><a href="/facts/Stac_Fada_Member/kh4CanyD">Stac Fada Member</a>, Scotland</li> <li><a href="/facts/Wabar_craters/1ytvAX7H">Wabar craters</a>, Saudi Arabia</li></ul> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Glossary_of_meteoritics/TbTPV1Ut">Glossary of meteoritics</a></li> <li><a href="/facts/Meteorite_shock_stage/hWrGVcPJ">Meteorite shock stage</a></li> <li><a href="/facts/Vitrified_sand/W67RlpFu">Vitrified sand</a></li></ul> <h2 id="external-links">External links</h2> Wikimedia Commons has media related to Impactite. <ul><li><a href="https://web.archive.org/web/20070808072836/http://www.lpi.usra.edu/publications/slidesets/craters/glossary.shtml">Meteorite crater glossary</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Stöffler, D.; Grieve, R.A.F. (1994). "Classification and Nomenclature of Impact Metamorphic Rocks: A Proposal to the IUGS Subcommission on the Systematics of Metamorphic Rocks". Lunar and Planetary Science Conference: 1347. Bibcode:1994LPI....25.1347S. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Schmid, Rolf; Fettes, Douglas; Harte, Ben; Davis, Eleutheria; Desmons, Jacqueline; Smulikowski, Witold; Sassi, Francesco; Brodie, Kate; Árkai, Péter (2007), Fettes, Douglas; Desmons, Jacqueline (eds.), "Classification and nomenclature scheme", Metamorphic Rocks, Cambridge University Press, pp. 3–110, doi:10.1017/cbo9780511628917.003, ISBN 978-0-511-62891-7 <a href="978-0-511-62891-7" target="_blank">978-0-511-62891-7</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"Impactites: Impact Breccia, Tektites, Moldavites, Shattercones". geology.com. Retrieved 2020-06-10. <a href="https://geology.com/meteorites/impactites.shtml" target="_blank">https://geology.com/meteorites/impactites.shtml</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"Impactites: Impact Breccia, Tektites, Moldavites, Shattercones". geology.com. Retrieved 2020-06-10. <a href="https://geology.com/meteorites/impactites.shtml" target="_blank">https://geology.com/meteorites/impactites.shtml</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"Impactites: Impact Breccia, Tektites, Moldavites, Shattercones". geology.com. Retrieved 2020-06-10. <a href="https://geology.com/meteorites/impactites.shtml" target="_blank">https://geology.com/meteorites/impactites.shtml</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Impactites: Impact Breccia, Tektites, Moldavites, Shattercones". geology.com. Retrieved 2020-06-10. <a href="https://geology.com/meteorites/impactites.shtml" target="_blank">https://geology.com/meteorites/impactites.shtml</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Staff (8 June 2015). "PIA19673: Spectral Signals Indicating Impact Glass on Mars". NASA. Retrieved 8 June 2015. <a href="https://photojournal.jpl.nasa.gov/catalog/PIA19673" target="_blank">https://photojournal.jpl.nasa.gov/catalog/PIA19673</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Schmid, Rolf; Fettes, Douglas; Harte, Ben; Davis, Eleutheria; Desmons, Jacqueline; Smulikowski, Witold; Sassi, Francesco; Brodie, Kate; Árkai, Péter (2007), Fettes, Douglas; Desmons, Jacqueline (eds.), "Classification and nomenclature scheme", Metamorphic Rocks, Cambridge University Press, pp. 3–110, doi:10.1017/cbo9780511628917.003, ISBN 978-0-511-62891-7 <a href="978-0-511-62891-7" target="_blank">978-0-511-62891-7</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Schmid, Rolf; Fettes, Douglas; Harte, Ben; Davis, Eleutheria; Desmons, Jacqueline; Smulikowski, Witold; Sassi, Francesco; Brodie, Kate; Árkai, Péter (2007), Fettes, Douglas; Desmons, Jacqueline (eds.), "Classification and nomenclature scheme", Metamorphic Rocks, Cambridge University Press, pp. 3–110, doi:10.1017/cbo9780511628917.003, ISBN 978-0-511-62891-7 <a href="978-0-511-62891-7" target="_blank">978-0-511-62891-7</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Temming, Maria. "Exotic Glass Could Help Unravel Mysteries of Mars". Scientific American. Retrieved 2015-06-15. <a href="http://www.scientificamerican.com/article/exotic-glass-could-help-unravel-mysteries-of-mars/" target="_blank">http://www.scientificamerican.com/article/exotic-glass-could-help-unravel-mysteries-of-mars/</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Schmid, Rolf; Fettes, Douglas; Harte, Ben; Davis, Eleutheria; Desmons, Jacqueline; Smulikowski, Witold; Sassi, Francesco; Brodie, Kate; Árkai, Péter (2007), Fettes, Douglas; Desmons, Jacqueline (eds.), "Classification and nomenclature scheme", Metamorphic Rocks, Cambridge University Press, pp. 3–110, doi:10.1017/cbo9780511628917.003, ISBN 978-0-511-62891-7 <a href="978-0-511-62891-7" target="_blank">978-0-511-62891-7</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Holland, Stuart S. (1976). Landforms of British Columbia: A Physiographic Outline (PDF). British Columbia, Canada. p. 127.{{cite book}}: CS1 maint: location missing publisher (link) <a href="http://cmscontent.nrs.gov.bc.ca/geoscience/PublicationCatalogue/Bulletin/BCGS_B048.pdf" target="_blank">http://cmscontent.nrs.gov.bc.ca/geoscience/PublicationCatalogue/Bulletin/BCGS_B048.pdf</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>"Impactites: Impact Breccia, Tektites, Moldavites, Shattercones". geology.com. Retrieved 2020-06-10. <a href="https://geology.com/meteorites/impactites.shtml" target="_blank">https://geology.com/meteorites/impactites.shtml</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Staff (8 June 2015). "PIA19673: Spectral Signals Indicating Impact Glass on Mars". NASA. Retrieved 8 June 2015. <a href="https://photojournal.jpl.nasa.gov/catalog/PIA19673" target="_blank">https://photojournal.jpl.nasa.gov/catalog/PIA19673</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Meteor Crater Bomblets <a href="https://www.meteorite-times.com/jims-fragments/meteor-crater-bomblets/" target="_blank">https://www.meteorite-times.com/jims-fragments/meteor-crater-bomblets/</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> </ol>