Era's of the World By ericbroten Jan 1, 1909 Cambrian 570 M Jan 1, 1909 Paleozoic Jan 1, 1921 Ordovician 500 M Jan 1, 1932 Silurian 435 M Jan 1, 1939 Devonian 395 M Jan 1, 1948 Carboniferous 345 M Jan 1, 1959 Permian 280 M Jan 1, 1964 Triassic 225 M Jan 1, 1964 Mesozoic Jan 1, 1974 Jurassic 195 M Jan 1, 1987 Cretaceous 136 M Jan 1, 1998 Tertiary 65 M Jan 1, 1998 Cenozoic Jan 1, 2010 Quaternary 1.8 M