Relative Dating - Determine the age of
sedimentary rock, and the fossils it contains, as
well as that of adjacent rock layers.
Radiometric Dating - Rocks contain radioactive isotopes of
certain elements. They can be used to determine the age of the
rocks by looking at the ratio of radioactive and non-radioactive
isotopes.
The radioactive isotopes decay at a constant tempo and are not
affected by climate or change of seismic activity
Radiometric dating measures in millions or billions ago (mya/bya).
Paleomagnetic Dating - certain rocks are magnetic, the magnetic poles of
the earth change and the axis of the earth is at a slant. THE DIRECTION OF
THE MAGNETIC FIELDS IN ROCKS IS USED TO DETERMINE RELATIVE
AGES.