Which of the following is the relatively most accurate method for dating of fossils?
- Radio-carbon method
- Uranium-lead method
- Potassium–argon method
- Electron-spin resonance method
Answer
(4) Electron-spin resonance method
Solution
As per NCERT, the age of fossils is determined by the radioactive dating method.
Radio-carbon dating works only up to about 50,000 years, while the uranium–lead and potassium–argon methods date the rocks around the fossil, not the fossil itself, and have large error ranges.
Electron-spin resonance (ESR) measures the electrons trapped in the crystal lattice of the fossil's own tooth enamel / bone, so it dates the fossil directly over a wide range with relatively small error.
∴ ESR is relatively the most accurate method among those given.
Answer: (4)