Principles of radioactive and stable isotope in geochemistry.
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Principle of Stable isotope geochemistry is that the study is based upon study of the relative and absolute concentrations of the elements and their isotopes in the Earth.
Variations in the abundance of these isotopes,is measured with Mass Spectrometers and this Stable isotope geochemistry has been applied to a great variety of problems, and common example is geothermometry ie to find age of a formation. Broadly, the field of isotope geochemistry is divided into two branches: stable and radiogenic isotope geochemistry.You can refer Chapter 9 of Geochemistry by W.M.White to know more in detail about this and you can freely down load this chapter using your google..