Therefore for Pb and the uranium series are very mobile or a geo-chemical process (such as different rates of bioaccumulation) fractionates the isotopes and produces different behaviour For analysis by alpha spectroscopy, Po alpha particle is about 5.1 Me V.
Particles emitted at these two energies can be identified using an alpha spectroscopy system.
Samples of iron meteorite from Canyon Diablo (Meteor Crater) Arizona were found to have the least radiogenic composition of any material in the solar system.
The U/Pb ratio was so low that no radiogenic decay was detected in the isotopic composition.
This makes it difficult to determine the analytical uncertainty on the age.
Sediment systems provide a natural storage system because Pb, Bi and Po are immobile or only mobilized together in these systems.
Successive collisions between accreted bodies led to the formation of larger and larger planetesimals, finally forming the Earth–Moon system in a giant impact event.
Pb isotopes cannot exchange and secular equilibrium is achieved.
Chondrules and calcium–aluminium-rich inclusions (CAIs) are spherical particles that make up chondritic meteorites and are believed to be the oldest objects in the solar system.
Hence precise dating of these objects is important to constrain the early evolution of the solar system and the age of the earth.