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GeochronologyGeochronology is the science of determining the age of rocks, fossils, and sediments. A variety of dating methods are used by geologists to achieve this. Dating methods - Radiometric techniques measure the decay of radioactive isotopes, and other radiogenic activity.
- Incremental techniques measure the regular addition of material to sediments or organisms.
- Correlation of marker horizons allow age-equivalence to be established between different sites.
Radiometric dating By measuring the rate of radiocative decay of a radioactive isotope with a known half-life, geologists can establish the absolute age of the parent material. A number of radioactive isotopes are used for this purpose, and depending on the rate of decay, are used for dating different geological periods. Other radiogenic dating techniques include: - Fission track dating
- Cosmogenic isotope dating
Incremental dating Incremental dating techniques allow the construction of year-by-year annual chronologies, which can be fixed (i.e. linked to the present day and thus calendar or sidereal time) or floating. References Lowe, J.J., and Walker, M.J.C. (1997), Reconstructing Quaternary Environments (2nd edition). Longman publishing ISBN 0582101662 Smart, P.L., and Frances, P.D. (1991), Quaternary dating methods - a user's guide. Quaternary Research Associaton Technical Guide No.4 ISBN 0907780033 Faure, G. (1997). Principles of isotope geology. Cambridge, Cambridge University Press. Dickin, A. P. (1995). Radiogenic Isotope Geology. Cambridge, Cambridge University Press. See also:
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