Book contents
- Frontmatter
- Contents
- Preface
- 1 Introduction to cosmochemistry
- 2 Nuclides and elements: the building blocks of matter
- 3 Origin of the elements
- 4 Solar system and cosmic abundances: elements and isotopes
- 5 Presolar grains: a record of stellar nucleosynthesis and processes in interstellar space
- 6 Meteorites: a record of nebular and planetary processes
- 7 Cosmochemical and geochemical fractionations
- 8 Radioisotopes as chronometers
- 9 Chronology of the solar system from radioactive isotopes
- 10 The most volatile elements and compounds: organic matter, noble gases, and ices
- 11 Chemistry of anhydrous planetesimals
- 12 Chemistry of comets and other ice-bearing planetesimals
- 13 Geochemical exploration of planets: Moon and Mars as case studies
- 14 Cosmochemical models for the formation of the solar system
- Appendix: Some analytical techniques commonly used in cosmochemistry
- Index
- References
8 - Radioisotopes as chronometers
Published online by Cambridge University Press: 05 June 2012
Book contents
- Frontmatter
- Contents
- Preface
- 1 Introduction to cosmochemistry
- 2 Nuclides and elements: the building blocks of matter
- 3 Origin of the elements
- 4 Solar system and cosmic abundances: elements and isotopes
- 5 Presolar grains: a record of stellar nucleosynthesis and processes in interstellar space
- 6 Meteorites: a record of nebular and planetary processes
- 7 Cosmochemical and geochemical fractionations
- 8 Radioisotopes as chronometers
- 9 Chronology of the solar system from radioactive isotopes
- 10 The most volatile elements and compounds: organic matter, noble gases, and ices
- 11 Chemistry of anhydrous planetesimals
- 12 Chemistry of comets and other ice-bearing planetesimals
- 13 Geochemical exploration of planets: Moon and Mars as case studies
- 14 Cosmochemical models for the formation of the solar system
- Appendix: Some analytical techniques commonly used in cosmochemistry
- Index
- References
Summary
Overview
So far we have discussed the materials that make up the solar system and the processes that caused those materials to be in their current state. We will now investigate the chronology of the events that led to the current state of the solar system. There are several different approaches to determine the timing of events. The sequence of events can often be established from spatial relationships among objects (e.g. younger things rest on older things). Absolute ages are provided by long-lived radioactive nuclides. Time intervals can be determined using short-lived radionuclides. Production of nuclides through irradiation by cosmic rays can also be used for age determinations. For a complete chronological picture, it is often necessary to use more than one method of age determination. In this chapter, we focus on the basic principles of radiometric dating. We review individual isotopic clocks, the types of materials that each can date, and the measurements that are made to determine the ages of different objects. In Chapter 9, we discuss the chronology of the solar system derived from these clocks.
Methods of age determination
Placing events in chronological order and attaching an absolute time scale to that order constitute one of the major areas of research in cosmochemistry. There is no single clock that works for everything, so the chronology of the solar system has been built on a wide variety of observations and measurements. The methods of age determination can be divided into two main types.
Information
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- Chapter
- Information
- Cosmochemistry , pp. 230 - 307Publisher: Cambridge University PressPrint publication year: 2010
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