Measuring Geologic Time (ES3B) Practice
I can explain the use of radioactive decay to date rocks. I can use Steno's laws, fossils, and radioactivity to estimate timing of geologic sequences.
- Explain what are index fossils and their value.
- A rock sample is found to have 25% of its U-235 left. How old is the rock sample?
- List the sequence of events (oldest to newest) that created this cross-section.
- In the cross-section above, how old is the siltstone layer E?