rocks can fall in love?. * the approximate age of a rock layer or fossil determined by the age of...

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Rocks can fall in love?

*Geological Dating

*Relative Dating

*The approximate age of a rock layer or fossil determined by the age of the layers or fossils above or beneath.

*The Law of Superposition

*A layer of sedimentary rock is older than the layer above it

*Exception One

*Rocks may be folded , tilted , or overturned out of position

*Exception Two

*Faults may push rock layers out of position

*3

*Intrusions of magma may cut through rock layers

*4-Unconformity

*Weathering may cause gap in order of layers

*Absolute Age!

*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.

*Half Life

*This is the time it takes half the mass of a radioactive isotope to decay into its stable form.

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