U pb dating half life

07 Jan

Over time, the amounts of Pb-206 and Pb-207 will change in some samples, as these isotopes are decay end-products of uranium decay (U-238 decays to Pb-206, and U-235 decays to Pb-207).

This causes the data points to separate from each other.

Young-Earthers have several methods which they claim to give "upper limits" to the age of the Earth, much lower than the age calculated above (usually in the thousands of years).

Helium is not light enough to escape the Earth's gravity (unlike hydrogen), and it will therefore accumulate over time.

The current level of helium in the atmosphere would accumulate in less than two hundred thousand years, therefore the Earth is young.

It looks like this: Most of the other measurements for the age of the Earth rest upon calculating an age for the solar system by dating objects which are expected to have formed with the planets but are not geologically active (and therefore cannot erase evidence of their formation), such as meteorites.

Below is a table of radiometric ages derived from groups of meteorites: As shown in the table, there is excellent agreement on about 4.5 billion years, between several meteorites and by several different dating methods.