Carbon Dating!

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Carbon Dating!. Done By Gabriel Tan 3I109 Hubert Heng 3I113. Background info. Carbon-14 dating is a way to determine the age of certain archaeological artefacts of a biological origin up to 50,000 years old. - PowerPoint PPT Presentation

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Carbon Dating!

Carbon Dating!Done By Gabriel Tan 3I109Hubert Heng 3I113Background infoCarbon-14 dating is a way to determine the age of certain archaeological artefacts of a biological origin up to 50,000 years old.Used in dating things such as bone, cloth, wood and plant fibres that were created by human activities.What about those older than 50k years?Dates later than 50,000 years can be found using other isotopes such asUranium -235 (half-life = 704 million years)Uranium -238 (half-life = 4.5 billion years)Thorium-232 (half-life = 14 billion years)Rubidium-87 (half-life = 49 billion years)More infoCarbon dating is a dating technique predicated upon three things:The rate at which the unstable radioactive C-14 isotope decays into the stable non-radioactive N-14 isotopeThe ratio of C-12 to C-14 found in a given specimenAnd the ratio C-12 to C-14 found in the atmosphere at the time of the specimen's death.ControversyDates derived are wildly inconsistentFor example, "One part of Dima (a famous baby mammoth discovered in 1977) was 40,000 RCY (Radiocarbon Years), another was 26,000 RCY, and 'wood found immediately around the carcass' was 9,000-10,000.Assumptions madeRate of decay (5730 year half-life) stayed constant throughout the unobservable pastRatio of C-12 to C-14 in the atmosphere has remained constant throughout the unobservable past So we can know what the ratio was at the time of the specimen's deathRadiocarbon is forming 28-37% faster than it is decayingHas not yet reached equilibrium.Ratio now is higher than in the pastAssumptions madeRatio of C-12 to C-14 in the atmosphere has remained constant throughout the unobservable past (contd)Ratio decreased during the industrial revolutionDramatic increase of CO2 by factoriesVolcanoes spew out CO2, decreasing the ratio.Specimens which lived and died during a period of intense volcanism would appear older than they really are if they were dated using this technique.

Answers for questionsAnswers for questionsCarbon Dating Gadgethttp://www2.hci.edu.sg/y09hci0227/carbon_dating.php/Biblography"HowStuffWorks "How Carbon-14 Dating Works"" Howstuffworks "Science" Web. 01 May 2011. ."Carbon Dating." Archaeology - AllAboutArchaeology.org. Web. 02 May 2011. ."Carbon 14 Dating - Math Central." Math Central. Web. 02 May 2011. . The EndThank you