2. Geologic Time

Radiometric Dating — Quiz

Test your understanding of radiometric dating with 5 practice questions.

Practice Questions

Question 1

Which characteristic of zircon crystals makes them particularly ideal for U–Pb dating of ancient igneous rocks?

Question 2

In an Rb–Sr isochron plot of ^87Sr/^86Sr versus ^87Rb/^86Sr, the y-intercept of the best-fit line represents which quantity?

Question 3

Compared to conventional K–Ar dating, the ^40Ar/^39Ar method provides which key advantage?

Question 4

A zircon sample retains 80% of its original ^238U. Given the half-life of ^238U is 4.47×10^9 years, what is its approximate crystallization age (in years)?

Question 5

If analytical precision contributes 3% uncertainty and calibration contributes 4% uncertainty to an isotopic ratio measurement, what is the combined relative uncertainty (in percent)?