Creature Cast. Characteristics of Crown Primates. This method. Microbe Matters. Remanent magnetization in ancient rocks that records the orientation of the earth's magnetic field and can be used to determine the location of the magnetic poles and the latitude of the rocks at the time the rocks were formed parent isotope: Want to watch this again later?
For rocks dating back to the beginning of the solar system, this requires extremely long-lived parent isotopes, making measurement of such rocks' exact ages imprecise.
Dating Rocks and Fossils Using Geologic Methods
So, what exactly is this thing called a half-life? New York: Email your Friend.