Question

The age of most ancient geological formation is estimated by:
A) Potassium Argon method
B) Carbon 14 dating method
C) Radium silicon method
D) Uranium Lead Method

Answer 1

Hint :Geological samples mainly include rock, ore, soil, fluid or gas, broken off from a larger mass or sample that is used for research purposes. It represents a smaller unit of the large mass, as it has the same characteristics and composition.

Complete Step By Step Answer:
The Uranium Lead Method, also known as the U-Pb method, is one of the most ancient and reliable radiometric dating methods. It is used to date rocks and crystals that were formed more than a billion years ago. It has a range of dating samples that are about $ 1billion $ to $ 4.5billion $ years old. It has a precision rate of $ 0.1 - 1 $ percent.
This method mainly has two decay chains. One in the Uranium Series which involves the decay of $ {}^{238}U \to {}^{206}Pb $ that has a half-life of 4.47 billion years and the second one in the Actinium Series involving the decay of $ {}^{235}U \to {}^{207}Pb $ , with a half-life of 710 million years.
The decay of Uranium to lead proceeds via a series of alpha and beta decays, in which $ {}^{238}U $ undergoes eight alpha and six beta decays whereas $ {}^{235}U $ undergoes seven alpha and four beta decays. The U-Pb dating method usually involves the coupled use of both the decay schemes. The use of one decay scheme leads to U-Pb isochron dating method which is similar to rubidium-strontium dating method.
Option A) is incorrect because the potassium argon method is used in geochronology and archaeology mainly.
Option B) is incorrect because the C-14 dating method is mainly used for finding the age of fossils and dead animals.
Option (C) is incorrect because this method is used for detecting trace radioactive impurities.
Hence the correct answer is Option D).

Note :
U-Pb method is usually used for Zircon Mineral Dating as it contains both uranium and thorium atoms, but rejects lead while forming. Because of this, the newly formed Zircon will have no lead present in it, and if any lead is found it will be radiogenic.