Note4Students
From UPSC perspective, the following things are important :
Prelims level: Carbon Dating
Mains level: Not Much
Central Idea: Allahabad high court ordered the ASI to conduct the carbon dating process of the ‘Shivling’ found in the premises of the Gyanvapi mosque, without causing any damage to the structure.
What is Carbon Dating?
- Carbon dating is a widely-used method for determining the age of organic materials that were once living.
- The method is based on the radioactive decay of Carbon-14 (C-14), an isotope of carbon with an atomic mass of 14.
- It works by measuring the ratio of C-12 to C-14 in the atmosphere, as well as in plants and animals that acquire carbon through photosynthesis or food consumption.
The half-life concept
- Carbon-14 has a half-life of 5,730 ± 40 years—i.e., half the amount of the radioisotope present at any given time will undergo spontaneous disintegration during the succeeding 5,730 years.
- Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon.
Limitations of Carbon Dating
- Carbon dating has certain limitations and cannot be applied in all circumstances.
- It is not suitable for determining the age of non-living things such as rocks.
- Carbon dating becomes less accurate for objects older than 40,000-50,000 years, as the amount of detectable C-14 becomes significantly small.
- Other radiometric dating methods are employed to determine the age of inanimate objects, which rely on the decay of radioactive elements present in the material.
- Examples of such methods include potassium-argon dating and uranium-thorium-lead dating, which analyze the ratios of specific isotopes to estimate the age of rocks.
Other Dating Methods
In addition to radiometric dating, there are alternative methods to determine the age of objects.
- Cosmogenic nuclide dating: CRN is one such method that utilizes radioactive decay to estimate age and is commonly used to study the age of ice cores in Polar Regions.
- Potassium-argon dating: A radiometric dating method that measures the ratio of potassium to argon isotopes in rocks to determine their age.
- Uranium-thorium-lead dating: A radiometric dating method that analyses the ratios of uranium, thorium, and lead isotopes in rocks to estimate their age.
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