7、h统series太古代Archaeozoicadj:Archean元古界proterozoic古生代Paleozoic寒武系cambrian奥陶系ordovician志留系Silurian泥盆系Devonian石炭系carboniferous二叠系Permian中生代Mesozoic三迭纪Triassic 侏罗纪的Jurassic白垩纪cretaceous新生界cenozoic第三纪tertiary第四纪Quaternary 上更新统epipleistocene全新统holocene古新统Paleocene epoch Ne