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| layers of rock, representing various periods of deposition |
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| the study of the deposition of plant or animal remains and the environmental conditions affecting their presentation |
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| rock formed when the deposition of sediments creates distinct layers, or strata |
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| major divisions of geologic time that are divided into periods and further subdivided into epochs |
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| divisions of periods (which are the major division of eras) in geologic time |
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| a hypothetical landmass in which all the continents were joined, approx 300-200 mya |
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| refers to various structures on Earth's surface, such as the continental plates. |
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| Steno's law of superposition |
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| the principle that the lower the stratum or layer, the older its age; the oldest layers are at the bottom, and the youngest are at the top |
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| stratigraphic correlation |
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| the process of matching up strata from several sites through the analysis of chemical, physical, and other properties. |
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| a relative (chemical) dating method that compares the accumulation of fluorine in animal and human bones from the same site |
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| dating methods that use predictable chemical changes that occur over time |
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| fossils that are from specified time ranges, are found in multiple locations, and can be used to determine the age of associated strata. |
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| relative dating methods that are based on material remains' time spans |
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| the earliest stone tools, in which simple flakes were knocked off to produce an edge used for cutting and scraping |
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| a chronometric dating method that uses a tree ring count to determine numerical age. |
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| the radiometric dating method in which the ratio of (14)C to (12)C is measured to provide an absolute date for a material younger than 50,000 years |
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| two or more forms of a chemical element that vary in the number of neutrons in the nucleus and by the atomic mass |
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| the time if takes for half of the radioisotopes in a substance to decay; used in various radiometric dating methods |
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| rock formed from the crystallization of molten magma, which contains the radioisotope (40)K; used in potassium-argon dating |
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| the radiometric dating method in which the ratio of (40)K to (40)Ar is measured to provide an absolute date for a material older than 200,000 years |
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| an absolute dating method based on the measurement of the number of tracks left by the decay of uranium-238 |
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Definition
| an absolute dating method for organic remains such as bone or shell, in which the amount of change in the amino acid structure is measured |
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| a kind of light used in amino acid dating because it allows amino acid changes to be observed and measured |
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| the chemical reaction resulting in the conversion of "L" amino acids to "D" amino acids for amino acid dating |
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| an absolute dating method based on the reversals of Earth's magnetic field |
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| electron spin resonance dating |
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Definition
| an absolute dating method that sues microwave spectroscopy to measure electrons' spins in various materials |
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| thermoluminescence dating |
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| a relative dating method in which the energy trapped n a material is measured when the object is heated |
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| marine protozoans that have variably shaped shells with small holes |
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