CG: n
CT: Carbon-14 dating
Radiocarbon dating, or carbon-14 dating, is a method for determining the age of a substance containing organic molecules by using the properties of radiocarbon, 14C, a radioactive isotope of carbon. The technique was developed in the late 1940s at the University of Chicago by Willard Libby, who received the Nobel Prize in Chemistry for his work in 1960. Carbon-14 is created continuously in the atmosphere by the bombardment of atmospheric nitrogen by cosmic rays. The resulting 14C combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis. Animals then acquire 14C by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter its 14C content begins to decrease as the 14C undergoes radioactive decay. Measuring the amount of 14C in an organic substance, such as a piece of wood or a fragment of bone, provides information that can be used to calculate when the animal or plant died. The older the sample is, the less 14C there is to be detected. Since the half-life of 14C (the period of time during, which half of the 14C in a sample will have decayed) is about 5730 years, the oldest dates of substances that can be reliably measured by this process are around 50,000 years.
S: SDir – https://www.sciencedirect.com/topics/earth-and-planetary-sciences/radiocarbon-dating (last access: 26 January 2025)
N: 1. – carbon (n): non-metallic element occurring naturally as diamond, graphite, or charcoal, 1789, coined 1787 in French by Lavoisier as charbone, from Latin carbonem (nominative carbo) “a coal, glowing coal; charcoal,” from PIE root ker- (3) “heat, fire.”
- Carbon 14, the long-lived radioactive isotope used in dating organic deposits, is from 1936. Carbon-dating (using carbon 14) is recorded from 1958. Carbon cycle is attested from 1912; carbon footprint was in use by 2001. Carbon-paper “paper faced with carbon, used between two sheets for reproduction on the lower of what is drawn or written on the upper” is from 1855, earlier it was carbonic paper (1850).
– 14 (adj): isotope of mass number 14 eight neutrons and six protons.
– dating (n): by 1939, verbal noun from date. Date: c. 1400, daten, “to mark (a document) with a date,” also “to assign to or indicate a date” (of an event), from date (n.1). Meaning “to mark as old-fashioned” is from 1895. Intransitive sense of “to have a date” is by 1850.
2. A method for dating material by means of carbon 14, a radioactive isotope with a half-life of 5600 years.
3. All living matter contains approximately one atom of carbon 14 in every trillion stable atoms of carbon…. By measuring the proportion of radioactive to stable carbon, the point in time at which the incorporation of radioactive carbon ceased (i. e., the point of death) can be calculated. This carbon-dating process, as it is called, can be used to determine the age of anything derived from living matter as, for example, the age of wooden artifacts.
The C14 technique has been and continues to be applied and used in many, many different fields including hydrology, atmospheric science, oceanography, geology, palaeoclimatology, archaeology and biomedicine.
4. Carbon-14 dating is the method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon-14). Carbon-14 is continually formed in nature by the interaction of neutrons with nitrogen-14 in the Earth’s atmosphere; the neutrons required for this reaction are produced by cosmic rays interacting with the atmosphere.
S: 1. Etymonline – https://www.etymonline.com/search?q=carbon, https://www.etymonline.com/search?q=dating&type=0, https://www.etymonline.com/word/date#etymonline_v_44370 (last access: 26 January 2025); MW – https://www.merriam-webster.com/dictionary/carbon%2014 (last access: 26 January 2025). 2 & 3. TERMIUM PLUS – https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html lang=eng&i=1&srchtxt=CARBON+14+DATING&index=enb&codom2nd_wet=1#resultrecs (last access: 26 January 2025). 4. EncBrit – https://www.britannica.com/science/carbon-14-dating (last access: 26 January 2025).
SYN: carbon dating, radioactive carbon dating, radiocarbon dating. (depending on context)
S: GDT – https://vitrinelinguistique.oqlf.gouv.qc.ca/fiche-gdt/fiche/26522385/datation-au-carbone-14 (last access: 26 January 2025)
CR: carbon-14
