| 释义 |
地质年代dìzhì niándài地壳中不同年代的岩石形成的时间和先后顺序。相对地质年代主要依据岩石的层位和岩石中的化石,指明岩石生成时间的顺序,如古生代、中生代、新生代等;绝对地质年代依据岩石中放射性同位素蜕变产物的含量,指明岩石生成至今的年数。{geochronology; dating of rock formation of the earth's crust. Relative age, such as Palaeozoic, Mesozoic and Cenozoic, refers to the time order in which rocks have formed by studying their position and the fossils in them. Absolute age refers to the number of years between the formation of the rocks and the present, established by studying decay radioactive spallation of radioisotopes in them.}见see‘地质年代表’。{Geological Timescale} |