Wā
- Cretaceous 30 ngā hua
- Tertiary 27 ngā hua
- Mesozoic 22 ngā hua
- Cenozoic 17 ngā hua
- Eocene 11 ngā hua
- Quaternary 11 ngā hua
- Triassic 11 ngā hua
- Carboniferous 9 ngā hua
- Jurassic 9 ngā hua
- Paleocene 9 ngā hua
- Paleozoic 9 ngā hua
- Cambrian 8 ngā hua
- Devonian 8 ngā hua
- Miocene 8 ngā hua
- Ordovician 7 ngā hua
- Permian 7 ngā hua
- Pliocene 7 ngā hua
- Oligocene 6 ngā hua
- Pleistocene 6 ngā hua
- Neogene 5 ngā hua
- Precambrian 5 ngā hua
- Silurian 4 ngā hua
- Paleogene 3 ngā hua
- 20th century 2 ngā hua
- 21st century 2 ngā hua
- Holocene 2 ngā hua
- 1790-1842 1 ngā hua
- 1892- 1 ngā hua
- 18th century 1 ngā hua
- 1910- 1 ngā hua
- 1933-1991 1 ngā hua
- 1934- 1 ngā hua
- 1946- 1 ngā hua
- 19th century 1 ngā hua
- Mississippian 1 ngā hua