Dating rocks with uranium 238 The best erotic sex chat
Relative dating is used to determine the relative ages of geologic strata, artifacts, historical events, etc. Both U-238, and C-14 (radiocarbon, for carbon dating) are used to estimate the age of certain types of matter.These atoms decay, and from the amount of atoms remaining, an estimate of the age can be made.The four isotopes are uranium-235, uranium-238, lead-207, and lead-206.
Since the formation of certain minerals precludes the existence of lead but not uranium, it can be certain that when the mineral was formed it no lead in it.
Carbon-14 is present in the air, and is absorbed by plants during photosynthesis.