Question

Age of fossils was previously determined by radioactive elements. The more precise recent method which has led to a revision of evolutionary period is

• A. Study of carbohydrate and protein in fossils.
• B. Study of conditions of fossilisation.
• C. Electrons spin resonance
• D. Presence of carbohydrate and protein in rocks.

Answer 1

The correct option is C Electrons spin resonance

ESR or Electron spin resonance is the advanced method of dating as it can determine the age of newly formed materials or previously heated rock. For example; teeth enamel, quartz, speleothems, igneous rocks, mollusc shells etc which previously could not be determined by radiocarbon dating. ESR dating method measures the trapped charge in the mineral. These trapped charges form para-magnetic centers in the crystal lattice that is detected via ESR spectrometry. The more the amount of trapped electrons; the more would be the magnitude of ESR signal, age and its radioactivity dosage.

On the other hand, the previously famous radiocarbon dating used Carbon 14 isotope to determine the age of organic objects. It could date(determine the age) organic fossils less than 50,000 years old. For example: Rocks of volcanic origin like the volcanic ash layers.

The correct answer is option C.