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Geologic Time

Jordyn Whiteside
Period 5
3/13/17
Across
A fossil that is used for dating and correlating the strata in which it is found
A method of dating geological or archaeological specimens by determining the relative proportions of particular radioactive isotopes present in a sample
A system of chronological dating that relates geological strata to time
A length or portion of time
A division of time equal to a billion years
Down
The time taken for the radioactivity of a specified isotope to fall to half its original value
A method for determining the age of an object containing organic material
Determining the order of past events without determining their exact age
A division of time that is a subdivision of a period and is subdivided into ages, corresponding to a series in chronostratigraphy
A subdivision of an eon and is itself divided into periods