TSV
Geological Time Periods - TSV
Geological time periods systematically classify Earth's approximately 4.6 billion year history according to the International Chronostratigraphic Chart established by the International Commission on Stratigraphy (ICS). It is divided into four major divisions: the Precambrian (Hadean, Archean, Proterozoic) and the Phanerozoic (Paleozoic, Mesozoic, Cenozoic). Each geological period is distinguished based on geological evidence including biological evolution, continental drift, and climate change, forming the foundation for scientific research and education.
geology
geological time
chronostratigraphy
Earth history
paleontology
Precambrian
Phanerozoic
Paleozoic
Mesozoic
Cenozoic
code slug name description category durationMa endMa startMa
EON-1 precambrian Precambrian The period from Earth's formation to approximately 541 million years ago, comprising about 88% of Earth's history. Supereon 4059 541 4600
EON-1-1 hadean Hadean From Earth's formation to approximately 4.0 billion years ago. No evidence of life. Eon 600 4000 4600
EON-1-2 archean Archean Approximately 4.0 to 2.5 billion years ago. Evidence of the oldest life appears. Eon 1500 2500 4000
EON-1-3 proterozoic Proterozoic Approximately 2.5 billion to 541 million years ago. Appearance of eukaryotes and oxygen increase. Eon 1959 541 2500
EON-2 phanerozoic Phanerozoic From approximately 541 million years ago to present. Era of multicellular life proliferation. Eon 541 0 541
ERA-1 paleozoic Paleozoic Approximately 541 to 252 million years ago. 'Ancient life era.' Era 289 252 541
PER-1-1 cambrian Cambrian Approximately 541 to 485 million years ago. The Cambrian explosion occurred. Period 56 485 541
PER-1-2 ordovician Ordovician Approximately 485 to 444 million years ago. Marine invertebrates flourished. Period 41 444 485
PER-1-3 silurian Silurian Approximately 444 to 419 million years ago. Life began colonizing land. Period 25 419 444
PER-1-4 devonian Devonian Approximately 419 to 359 million years ago. 'Age of Fishes.' Period 60 359 419
PER-1-5 carboniferous Carboniferous Approximately 359 to 299 million years ago. Large forests and coal deposits formed. Period 60 299 359
PER-1-6 permian Permian Approximately 299 to 252 million years ago. Continents united and a great extinction occurred. Period 47 252 299
ERA-2 mesozoic Mesozoic Approximately 252 to 66 million years ago. 'Age of Reptiles.' Era 186 66 252
PER-2-1 triassic Triassic Approximately 252 to 201 million years ago. Dinosaurs and mammals appeared. Period 51 201 252
PER-2-2 jurassic Jurassic Approximately 201 to 145 million years ago. The golden age of dinosaurs. Period 56 145 201
PER-2-3 cretaceous Cretaceous Approximately 145 to 66 million years ago. Flowering plants and dinosaur extinction. Period 79 66 145
ERA-3 cenozoic Cenozoic Approximately 66 million years ago to present. 'Age of Mammals.' Era 66 0 66
PER-3-1 paleogene Paleogene Approximately 66 to 23 million years ago. Adaptive radiation of mammals. Period 43 23 66
PER-3-2 neogene Neogene Approximately 23 to 2.58 million years ago. Expansion of grasslands and ape evolution. Period 20.42 2.58 23
PER-3-3 quaternary Quaternary Approximately 2.58 million years ago to present. Ice ages and human evolution. Period 2.58 0 2.58