11.11 Age of earth Flashcards
1
Q
Radioisotopic dating
A
- Based on empirical measurements of half-lifes.
- Ratio of parent to daughter isotopes in a crystal.
2
Q
What rocks can be radio-isotopically dated?
A
Igneous rocks and sea floor, as they form from magma.
Sedimentary deposits cannot be dated, as they might not have formed from there.
3
Q
How old is the earth?
A
4.54 billion (based on meteorites).
