Carbon 14 dating fossils updating jeppeson database
Why do ancient samples of coal, diamonds and other carbon-containing materials consistently contain  The first such curve was published by: Arnold, JR and WF Libby. High-precision (super 14C measurement of Irish oaks to show the natural 14C variations from AD 1840 to 5210 BC. Age determinations by radiocarbon content: Checks with samples of known age. Subsequent revisions have been made, e.g., Reimer, PJ et al. A final assumption is that the various rates of flow of carbon-14 among the respective geophysical reservoirs must be constant, and the residence time of carbon-14 in the various reservoirs must be short relative to its half-life. (Riverside, CA: La Sierra University Press, 1997), 183. Carbon-14 dating models and experimental implications. Origins 24(2, 1997):50-64  The deep ocean waters are estimated to take about 1000 years to circulate back to the surface: Aitken, MJ. If these three conditions are met, the initial concentration of C in the sample can be estimated. Violations in the atmosphere result from volcanic eruptions that occasionally add C.
Researchers have found a reason for the puzzling survival of soft tissue and collagen in dinosaur bones - the bones are younger than anyone ever guessed.
It is known that such variations have occurred, but it is thought they can be corrected for by comparing a sample’s C level with the standard curve constructed using samples of known age.
Another assumption is that the amounts of carbon-14 present in the geophysical reservoirs must be constant.
This can be done very accurately, although some samples may be difficult to work with.
Beyond this, the accuracy of the date depends on the reliability of the assumptions used in interpreting the measurements (see below).
In most cases, the three methods produced similar results.