Geochronology is the field of science concerned with determining the ages of rocks and other stuff. In this book we attempt to outline the basic principles used for the quantification of geological time focusing on the radio-isotopic dating techniques. We are attempting to be inclusive about the methodologies and applications however there is a focus on the mainstream chronometers and the application of these to the quantification of geologic time.

## Preface: Historical Development of Geochronology

- Early Attempts at Quantifying Geologic Time
- Discovery of Radioactivity
- Development of Modern Mass Spectrometry

## Part One - The Basics

## Part Two - Radioisotopic Dating

- Introduction
- U-Pb Decay Scheme
- U-Series Disequilibria
- (U-Th)/He
- K-Ar Decay Scheme and 40Ar/39Ar
- Re-Os
- Rb-Sr

## Part Three - Mass Spectrometry

- Principles of mass spectrometry
- Gas-source mass spectrometry
- Thermal-ionization mass spectrometry
- Secondary ion mass spectrometry
- Inductively-coupled plasma mass spectrometry
- Sample introduction by laser ablation

## Part Four - Uncertainties

- Definitions and Concepts
- Random and/or Systematic
- Excess Variance
- Weighted means
- Isochrons and Linear Regression
- Metrology and Traceability

## Part Five - Application

- Introduction
- Age of the Earth
- Tectonic Applications
- Stratigraphic Applications
- Thermochronology