{"id":819,"date":"2021-07-07T11:30:13","date_gmt":"2021-07-07T15:30:13","guid":{"rendered":"https:\/\/wpstaging.whoi.edu\/site\/coastalgroup\/?page_id=819"},"modified":"2022-01-13T14:17:15","modified_gmt":"2022-01-13T18:17:15","slug":"c14-dating-techniques","status":"publish","type":"page","link":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/about\/how-we-work\/lab-methods\/c14-dating-techniques\/","title":{"rendered":"C14 Dating Techniques"},"content":{"rendered":"\n\n\t<h1>C14 Dating Techniques<\/h1>\n<h2>What is\u00a0<sup>14<\/sup>C?<\/h2>\n<p>Carbon is one of the elements which all living things are composed of. The most common form of carbon is carbon-12 which has 6 protons and 6 neutrons. 99 percent of all the carbon in the world is carbon-12 but some carbon atoms (<strong>isotopes)\u00a0<\/strong>have additional 1 or 2 neutrons. These isotopes are called carbon-13 and carbon-14 respectively.<\/p>\n<h2>Where does\u00a0<sup>14<\/sup>C come from?<\/h2>\n\t\t\t\t<img loading=\"lazy\" src=\"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-content\/uploads\/sites\/139\/2021\/07\/c14-300x175.jpg\" alt=\"Carbon\" height=\"175\" width=\"300\" title=\"c14-300x175\" \/>\n\t<p>Carbon-14, the isotope with 8 neutrons, is created in the atmosphere. Cosmic rays enter the atmosphere from space and create energetic neutrons. When one of these energetic neutrons collides with a nitrogen atom (7 protons and 7 neutrons), it forces out one of the protons, creating a Carbon-14 atom (6 protons and 8 neutrons).<\/p>\n\t\n<h2>How does\u00a0<sup>14<\/sup>C tell us the age of organic materials?<\/h2>\n\t\t\t\t<img loading=\"lazy\" src=\"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-content\/uploads\/sites\/139\/2021\/07\/c142-300x254.jpg\" alt=\"leaves found within a core\" height=\"254\" width=\"300\" title=\"c142-300x254\" \/>\n\t\tThis picture shows leaves found within a core, before they are removed for C14 analysis.\n\t<p><sup>14<\/sup>C acts much like regular carbon-12 so it is taken up by plants through photosynthesis, and by animals when they eat plants.<\/p>\n<p>Though\u00a0<sup>14<\/sup>C is present in all living things, it is a rare, unstable isotope which means that over time it decays. Every 5730 years, half of the\u00a0<sup>14<\/sup>C atoms within a sample decay. To determine the age of a sample we compare the ratio of Through comparing the amount of\u00a0<sup>14<\/sup>C atoms remaining in the sample and the amount of\u00a0<sup>14<\/sup>C in an atmospheric standard, we can discover how many years old the sample is.<\/p>\n\t<h2>How do we use\u00a0<sup>14<\/sup>C dating?<\/h2>\n<p>Carbon-14 (<sup>14<\/sup>C) dating is used to determine the age of organic material which we discover in our cores, such as leaves, roots, or bone which are found within the sediment core.<\/p>\n<h2>Explanation of results<\/h2>\n\t\t\t\t<img loading=\"lazy\" src=\"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-content\/uploads\/sites\/139\/2021\/07\/c143-241x300.jpg\" alt=\"leaves found within a core, before they are removed for C14 analysis.\" height=\"300\" width=\"241\" title=\"c143-241x300\" \/>\n\t\tThis picture shows leaves found within a core, before they are removed for C14 analysis.\n\t<p>After being pulled from sediment cores and prepared in the lab samples are sent to the National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS) to be analyzed (more on that process here <a href=\"http:\/\/www.pbs.org\/wgbh\/nova\/tech\/radiocarbon-dating.html\">http:\/\/www.pbs.org\/wgbh\/nova\/tech\/radiocarbon-dating.html<\/a>). NOSAMS returns results in a spreadsheet which shows the age of the sample and the amount of error. These results are then calibrated and used to model the age of the sediment based upon depth. (example excel file saved in CRLers folder)<\/p>\n<p>Dry, clean organic material in a vial ready to be sent to NOSAMS for analysis<\/p>\n\t\n<a href=\"https:\/\/www2.whoi.edu\/site\/nosams\/\">What is Carbon Dating?<\/a><br \/>\nfrom NOSAMS\n<a href=\"http:\/\/science.howstuffworks.com\/environmental\/earth\/geology\/carbon-141.htm\">How Carbon-14 Dating Works<\/a><br \/>\nfrom how stuff works\n<a href=\"http:\/\/www.pbs.org\/wgbh\/nova\/tech\/radiocarbon-dating.html\">Radiocarbon Dating<\/a><br \/>\nfrom NOVA, WGBH\n<a href=\"http:\/\/hyperphysics.phy-astr.gsu.edu\/hbase\/nuclear\/cardat.html\">Carbon Dating<\/a><br \/>\nfrom Hyperphysics\n\n","protected":false},"excerpt":{"rendered":"<p>C14 Dating Techniques What is\u00a014C? Carbon is one of the elements which all living things are composed of. The most common form of carbon is carbon-12 which has 6 protons and 6 neutrons. 99 percent of all the carbon in the world is carbon-12 but some carbon atoms (isotopes)\u00a0have additional 1 or 2 neutrons. These&hellip;<\/p>\n","protected":false},"author":26,"featured_media":0,"parent":797,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/pages\/819"}],"collection":[{"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/users\/26"}],"replies":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/comments?post=819"}],"version-history":[{"count":3,"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/pages\/819\/revisions"}],"predecessor-version":[{"id":1431,"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/pages\/819\/revisions\/1431"}],"up":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/pages\/797"}],"wp:attachment":[{"href":"https:\/\/www2.whoi.edu\/site\/coastalgroup\/wp-json\/wp\/v2\/media?parent=819"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}