From Chronology to Radioactive Dating
从断代到年龄测定

Time is an important conception in stratigraphy.Early age determination was based on chronostratic unit.With the application of radioactive elements,radioactive dating has been widely used in geology. According to the characteristics of radioactive elements,dating methods can be classified in to three types,which are based on the lifetime of single radioactive element,the parent_daughter system of radioactive element and the nuclear radiation respectively.Each dating method has its valid range and limiation of the sample.Meanwhile,those methods need the knowledge of different fields or branches of sciences and technology.