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Vocab 1.30
| Question | Answer |
|---|---|
| Uniformitarisnism | A principle that geologic processes that occurred in the past can be explained by current geologic processes |
| Relative Age | The age of an object in relation to the ages of other objects |
| Law of Superposition | The principle that a sedimentary rock layer is older than the layers below it if the layers aren't disturbed |
| Law of Crosscutting Relationships | The principle that a fault or body of rock is younger than any other body of rock that it cuts through |
| Absolute Age | The numeric age of an object or event, often stated in years before the present, as established by an absolute-dating process such as radio-metric dating |
| Varve | A pair of sedimentary layers (one coarse, one fine) that is deposited in an annual cycle, commonly in glacial lakes, and that can be used to determine absolute age |
| Radiometric Dating | A method of determining the absolute age of an object by comparing the relative percentages of a radioactive (parent) isotope and a stable (daughter) isotope |
| Half-Life | The time required for half of a sample of a radioactive isotope to break down by radioactive decay to form a daughter isotope |
| Parent Isotope | The original radioactive isotope |
| Daughter Isotope | The final stable isotope |