Exercise 4
A times series of [latex]_{}^{3}H[/latex] values in precipitation from Lincoln, Nebraska, USA, (Michel et al., 2018) is available and a groundwater sample collected in 2012 has a measured tritium concentration of 4.5 TU. In the spreadsheet provided on the web page for this book↗, annual [latex]_{}^{3}H[/latex] has been determined as an unweighted mean value (annual mean) and a weighted mean based on monthly precipitation from Lincoln, Nebraska, USA↗.
Construct a decay curve and answer the following questions:
- What is the minimum groundwater age for this sample, based on Equation (13)?
- Compare the answer above to the minimum age determined using a graphical method.