Absolute Age vs Relative Dating Absolute dating is
Absolute Age vs. Relative Dating � Absolute dating is the process of determining an approximate computed age ◦ The most common way this is done is called Radiometric Dating. �This is based on measuring the amount of radioactive decay.
Relative dating � This IS the science of determining the relative order of past events, without necessarily determining their absolute age. � This � In IS NOT going out with your cousin! geology rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another.
Tools used for Relative Dating � 1) Index Fossils ◦ Fossils of organisms with known periods of existence. ◦ Allow Scientists to approximate the age of certain rock layers.
2) Law of Superposition In any undisturbed sequence of strata, the oldest layer is at the bottom of the sequence, and the youngest layer is at the top of the sequence.
3) The Cross-Cutting Law feature that cuts across a body of sediment or rock is younger than the body of sediment or rock that it cuts across. � Examples include fractures, faults, igneous intrusions � Any ◦ NOTE: �A fracture is a crack in rock. � A fault is a fracture along which movement has occurred.
4) The Law of Inclusions � If one rock body contains fragments of another rock body it must be younger than the fragments of rock it contains. SO…The inclusions are older than the rocks which contain them. Inclusions “B” are older than “C”
inclusion
Can you rank the layers by age?
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