Radiometric dating technology
Find additional lessons, activities, videos, and articles that focus on relative and absolute dating.and most refined of the radiometric dating schemes.During the alpha decay steps, the zircon crystal experiences radiation damage, associated with each alpha decay.This damage is most concentrated around the parent isotope (U and Th), expelling the daughter isotope (Pb) from its original position in the zircon lattice.These fission tracks act as conduits deep within the crystal, providing a method of transport to facilitate the leaching of lead isotopes from the zircon crystal.Loss (leakage) of lead from the sample will result in a discrepancy in the ages determined by each decay scheme.The universe is full of naturally occurring radioactive elements.Radioactive atoms are inherently unstable; over time, radioactive "parent atoms" decay into stable "daughter atoms." When molten rock cools, forming what are called igneous rocks, radioactive atoms are trapped inside. By measuring the quantity of unstable atoms left in a rock and comparing it to the quantity of stable daughter atoms in the rock, scientists can estimate the amount of time that has passed since that rock formed.
However, to read any clock accurately we must know where the clock was set at the beginning.In areas with a high concentration of the parent isotope, damage to the crystal lattice is quite extensive, and will often interconnect to form a network of radiation damaged areas.Fission tracks and micro-cracks within the crystal will further extend this radiation damage network.It can be used to date rocks that formed and crystallised from about 1 million years to over 4.5 billion years ago with routine precisions in the 0.1–1 percent range. This mineral incorporates uranium and thorium atoms into its crystal structure, but strongly rejects lead when forming.
As a result, newly-formed zircon deposits will contain no lead, meaning that any lead found in the mineral is radiogenic.Most people think that radioactive dating has proven the earth is billions of years old.