# What is radioactive dating of rocks Hotchatdirect uk

It suffers from the problem that rubidium and strontium are very mobile and may easily enter rocks at a much later date to that of formation.

This method for rock dating is based on the decay of potassium-40 into argon: until the rock solidifies, argon can escape, so it can in theory date the formation of rock.

Carbon dating works on organic matter, all of which contains carbon.

However it is less useful for dating metal or other inorganic objects.

Note that although carbon-14 dating receives a lot of attention, since it can give information about the relatively recent past, it is rarely used in geology (and almost never used to date fossils).

Carbon-14 decays almost completely within 100,000 years of the organism dying, and many fossils and rock strata are hundreds of times older than that.

A proper radiometric date should read years before present (with 1950 being present) ± range/2 at x standard deviations (Xσ)', but is often reported as a single year or a year range, like 1260–1390 CE (the date for the Shroud of Turin).Symbolically, the process of radioactive decay can be expressed by the following differential equation, where N is the quantity of decaying nuclei and k is a positive number called the exponential decay constant.The meaning of this equation is that the rate of change of the number of nuclei over time is proportional only to the number of nuclei.This is consistent with the assumption that each decay event is independent and its chance does not vary over time.The solution is: where is the half-life of the element, is the time expired since the sample contained the initial number atoms of the nuclide, and is the remaining amount of the nuclide.