Radiocarbon measurements, carbon dynamics

Appendix 2. Modeling Carbon Dynamics Using Radiocarbon Measurements 256... 

APPENDIX 2. MODELING CARBON DYNAMICS USING RADIOCARBON MEASUREMENTS... 

Trumbore, S. E. (1993). Comparison of carbon dynamics in tropical and temperate soils using radiocarbon measurements. Global Biogeochem. Cycles 7(2), 275-290. 

If it can be assumed that the rate of production has not varied over time, and thus that a dynamic equilibrium has formed, and if it is possible to extract clean sample carbon, unaltered apart from the decline in and to measure its current concentration, it is possible using eqn [1] to calculate the elapsed time since the death of the organism. In practice, the process is far more complicated than this brief description indicates. Principally, one of the basic assumptions, that the rate of formation is constant, is known to be incorrect. The rate has, in fact, varied over time in response to a number of effects, principally fluctuations in the cosmic-ray flux with changes in the geomagnetic field and in solar activity. Because of this, no radiocarbon measurement equates directly with a calendar date, and all such measurements must be calibrated before use. 

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