For in carbon 14 dating
It then diffuses throughout the atmosphere, and is absorbed by vegetation (plants need carbon dioxide in order to make sugar by photosynthesis). While it is alive, each plant or animal takes in carbon dioxide from the air.
Animals also feed on some carbon 14 in all of that carbon dioxide.
Now let us consider the underlying assumptions about radiocarbon dating that are made in order to make it a workable method, even though not a reliable one. Frankly, in most instances, it would be impossible to be certain how much of this secondary or intrusive carbon had entered the sample from elsewhere.
(1) Atmospheric carbon: For the past several million years, the air around us had the same amount of atmospheric carbon that it now has(2) Oceanic carbon: During that time, the very largeamount of oceanic carbon has not changed in size.(3) Cosmic rays: Cosmic rays from outer space have reached the earth in the same amounts in the past as now.(4) Balance of rates: Both the rate of formation and rate of decay of carbon 14 have always in the past remained in balance.(5) Decay rates: The decay rate of carbon 14 has never changed.(6) No contamination: Nothing has ever contaminated any specimen containing carbon 14.(7) No seepage: No seepage of water or other factor has brought additional carbon 14 to the sample since death occurred.(8) Amount of carbon 14 at death: The fraction of carbon 14, which the living thing possessed at death, is (9) Carbon 14 half-life: The half-life of carbon 14 has been accurately determined. (2) VARIATIONS WITHIN SAMPLES-Then there is the problem of variations within each of the samples.
In reality, there is not one instance in which we can point to a C-14 sample and declare with certainty that EVEN ONE of those assumptions applies to it. (3) LOSS OF CARBON 14—Rainfall, lakes, oceans, and below-ground moisture will cause a loss of Carbon 14, and thus ruin its radiation clock.
Willard Libby’s training was in science, not history, so he and his co-workers were initially startled to learn that recorded history (actual historical events) only goes back to about 3000 B. They had been taught in school that it extended back 20,000 years! (4) CHANGES IN ATMOSPHERIC CARBON—In addition, it is not known what carbonic and atmospheric conditions were like in ancient times.
Willard Libby and his associates discovered carbon 14 (C 14) as a method for the dating of earlier organic materials.
But later research revealed that its inaccuracy increases in accordance with the actual age of the material (*C. Reed,“Animal Domestication in the Prehistoric Near East,” in Science, 130, 1959, p.
The earliest Egyptian dates should probably be lowered to 2200 B. Evidence is surfacing that changes have occurred which would invalidate ancient dates determined by carbon-14 analysis.1630; University of California at Los Angeles, “On the Accuracy of Radiocarbon Dates,”in Geochronicle, 2, 1966 [Libby’s own laboratory]). This method of dating is called carbon-14 dating, C-14 dating, or radiocarbon dating.Within about 12 minutes after being struck by cosmic rays in the upper atmosphere, the carbon 14 combines with oxygen, to become carbon dioxide that has carbon 14 in it.(2) In the 12th and early 13th centuries, there was unusually high sunspot activity for a number of years.At that time, there was less C-14 production, warmer climate, increased glacial melt, and unusually brilliant displays of the aurora borealis.
C.) Like many other bright hopes that men had at last found a way to date things prior to 4300 years ago, radiocarbon dating has turned out to be just another headache to conscientious scientists. Spot production radically affects radiocarbon production in the atmosphere.