geological age; geologic time
Meanings
3 senses · 8 examplesnoun
geological age; the time and sequence of rock formation in the Earth's crust
Divided into relative and absolute dating methods. Fundamental concept in stratigraphy and historical geology.
Geological ages help us understand the evolutionary history of the Earth.
Scientists determine the age of fossils by studying geological time.
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Different geological ages correspond to different biological communities.
noun
relative geological age; dating based on stratigraphic position and fossils
technicalAlso called 相对年代. Determines sequence (older/younger) but not exact numerical age. Based on the Law of Superposition and fossil succession.
Relative geological age is mainly determined using the principle of superposition.
By comparing fossils, we can determine the relative geological ages of two strata.
noun
isotopic age; absolute geological age; numerical dating based on radioactive isotope decay
technicalFormerly called 绝对地质年代 (absolute geological age). Provides numerical age in years (e.g., 'this rock is 100 million years old'). Uses methods like radiocarbon dating, potassium-argon dating, and uranium-lead dating.
Isotopic dating shows this rock is one billion years old.
Radiocarbon dating can be used to determine the age of relatively young geological samples.
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Absolute geological age provides a precise time scale for Earth's history.