Analysis of zircon crystals separated from the sandstone showed that the 206Pb/238U ratio was is 0.90, How do you work out an estimate for the age of the zircon crystallization assuming that the decay of 238U to 206Pb is 4.47x10^9 Years?

Analysis of zircon crystals separated from the sandstone showed that the 206Pb/238U ratio was is 0.90, How do you work out an estimate for the age of the zircon crystallization assuming that the decay of 238U to 206Pb is 4.47x10^9 Years?

Geological processes for zircon + sandstone?

Zircon crystals formed when a granite magma crystallised. Since then, geological processes have caused some of these crystals to end up with grains in a sandstone. What sequence of events would account for this? and what implications would this make for the age of the sandstone assuming that the 206Pb/238U ratio is 0.90 with the radiometric decay worked out as: t = 1/k x ln (1+ D/P) where t = the age of the sample D = number of atoms of the daughter isotope in the sample P = number of atoms of the parent isotope in the sample k = decay constant of the parent isotope ln = natural logarithm The half-life of 238U is given to us as 4.47 billion years... click for more