*
Rocks can fall in love?
* The approximate age of a rock layer or fossil
determined by the age of the layers or fossils
above or beneath.
*
* A layer of sedimentary rock is older than the layer
above it
*
* Rocks may be folded , tilted , or overturned
out of position
*
* Faults may push rock layers out of position
*
* Intrusions of magma may cut through rock
layers
*
* Weathering may cause gap in order of layers
*
* This is the actual age of a substance.
* This is measured by using the half life of
radioactive elements.
* Radioactive elements - These are isotopes
(varieties of certain elements containing
different masses) of elements whose nucleus is
decaying (breaking down, releasing energy and
particles at a constant rate).
*
* EX. Uranium 238 Carbon 14
* - The number stands for the mass of the
isotope
* - Uranium decays until it reaches lead 206.
When an element stops decaying it is
considered stable.
* This is the time it takes half the mass of a
radioactive isotope to decay into its stable
form.
*