Geologic Time
The geological time scale is a system of chronological dating that relates geological rock strata to time, and is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history.
Geologic Time Scale
├Phanerozoic: 541 Ma–present
├Cenozoic: 66 Ma–present
├Quaternary: 2.6 Ma–present
├Holocene: 11.7 Ka–present
├Meghalayan: 4.2 Ka - present
├Northgrippian: 8.2 - 4.2 Ka
└Greenlandian: 11.7 - 8.2 Ka
└ Pleistocene: 2.58–0.01 Ma
├Stage 4 0.129–0.012 Ma
├Chibanian (Middle) 0.774–0.129 Ma
├Calabrian (Lower) 1.80–0.774 Ma
└Gelasian (Lower) 2.58–1.80 Ma
├Neogene: 23.03–2.58 Ma
├Pliocene: 5.33–2.58 Ma
├Piacenzian: 3.60–2.58 Ma
└Zanclean: 5.33–3.60 Ma
└ Miocene: 23.03–5.33 Ma
├Messinian: 7.25–5.33 Ma
├Tortonian: 11.63–7.25 Ma
├Serravallian: 13.82–11.63 Ma
├Langhian: 15.97–13.82 Ma
├Burdigalian: 20.44–15.97 Ma
└Aquitanian: 23.03–20.44 Ma
└ Paleogene: 66–23 Ma
├Oligocene: 33.9–23.0 Ma
├Chattian: 27.82–23.03 Ma
└Rupelian: 33.9–27.82 Ma
├Eocene: 56.0–33.9 Ma
├Priabonian: 37.71–33.9 Ma
├Bartonian: 41.2–37.71 Ma
├Lutetian: 47.8–41.2 Ma
└Ypresian: 56.0–47.8 Ma
└ Paleocene: 66.0–56.0 Ma
├Thanetian: 59.2–56.0 Ma
├Selandian: 61.6–59.2 Ma
└Danian: 66.0–61.6 Ma
├Mesozoic: 252–66 Ma
├Cretaceous: 145–66 Ma
├Late Cretaceous: 100.5–66.0 Ma
├Maastrichtian: 72.1–66.0 Ma
├Campanian: 83.6–72.1 Ma
├Santonian: 86.3–83.6 Ma
├Coniacian: 89.8–86.3 Ma
├Turonian: 93.9–89.8 Ma
└Cenomanian: 100.5–93.9 Ma
└ Early Cretaceous: 145.0–100.5 Ma
├Albian: 113.0–100.5 Ma
├Aptain: 125.0–113.0 Ma
├Barremian: 129.4–125.0 Ma
├Hauterivian: 132.6–129.4 Ma
├Valanginian: 139.8–132.6 Ma
└Berriasian: 145.0–139.8 Ma
├Jurassic: 201–145 Ma
├Late Jurassic: 163.5–145.0 Ma
├Tithonian: 152.1–145.0 Ma
├Kimmeridgian: 157.3–152.1 Ma
└Oxfordian: 163.5–157.3 Ma
├Middle Jurassic: 174.1–163.5 Ma
├Callovian: 166.1–163.5 Ma
├Bathonian: 168.3–166.1 Ma
├Bajocian: 170.3–168.3 Ma
└Aalenian: 174.1–170.3 Ma
└ Early Jurassic: 201.3–174.1 Ma
├Toarcian: 182.7–174.1 Ma
├Pliensbachian: 190.8–182.7 Ma
├Sinemurian: 199.3–190.8 Ma
└Hettangian: 201.3–199.3 Ma
└ Triassic: 252–201 Ma
├Late Triassic: 237–201.3 Ma
├Rhaetian: 208.5–201.3 Ma
├Norian: 227–208.5 Ma
└Carnian: 237–227 Ma
├Middle Triassic: 247.2–237 Ma
├Ladinian: 242–237 Ma
└Anisian: 247.2–242 Ma
└ Early Triassic: 252.2–247.2 Ma
├Olenekian: 251.2–247.2 Ma
└Induan: 251.9±0.06–251.2 Ma
└ Paleozoic: 541–252 Ma
├Permian: 299–252 Ma
├Lopingian: 259.1–251.902 Ma
├Changhsingian: 254.14–251.902 Ma
└Wuchiapingian: 259.1–254.14 Ma
├Guadalupian: 272.95–259.1 Ma
├Capitanian: 265.1–259.1 Ma
├Wordian: 268.8–265.1 Ma
└Roadian: 272.95–268.8 Ma
└ Cisuralian: 298.9–272.95 Ma
├Kungurian: 283.5–272.95 Ma
├Artinskian: 290.1–283.5 Ma
├Sakmarian: 295.0–290.1 Ma
└Asselian: 298.9–295.0 Ma
├Carboniferous: 359–299 Ma
├Pennsylvanian: 323.2–298.9 Ma
├Gzhelian: 303.7–298.9 Ma
├Kasimovian: 307.0–303.7 Ma
├Moscovian: 315.2–307.0 Ma
└Bashkirian: 323.2–315.2 Ma
└ Mississippian: 358.9–323.2 Ma
├Serpukhovian: 330.9–323.2 Ma
├Visean: 346.7–330.9 Ma
└Tournaisian: 358.9–346.7 Ma
├Devonian: 419–359 Ma
├Upper Devonian: 382.7–358.9 Ma
├Famennian: 372.2–358.94 Ma
└Frasnian: 382.7–372.2 Ma
├Middle Devonian: 393.3–382.7 Ma
├Givetian: 387.7–382.7 Ma
└Eifelian: 393.3–387.7 Ma
└ Lower Devonian: 419.2–393.3 Ma
├Emsian: 407.6–393.3 Ma
├Pragian: 410.8–407.6 Ma
└Lochkovian: 419.2–410.8 Ma
├Silurian: 444–419 Ma
├Přídolí: 423.0–419.2 Ma
├Ludlow: 427.4–423.0 Ma
├Ludfordian: 425.6–423.0 Ma
└Gorstian: 427.4–425.6 Ma
├Wenlock: 433.4–427.4 Ma
├Homerian: 430.5–427.4 Ma
└Sheinwoodian: 433.4–430.5 Ma
└ Llandovery: 443.8–433.4 Ma
├Telychian: 438.5–433.4 Ma
├Aeronian: 440.8–438.5 Ma
└Rhuddanian: 443.8–440.8 Ma
├Ordovician: 485–444 Ma
├Late Ordovician: 458.4–443.8 Ma
├Hirnantian: 445.2–443.8 Ma
├Katian: 453.0–445.2 Ma
└Sandbian: 458.4–453.0 Ma
├Middle Ordovician: 470.0–458.4 Ma
├Darriwilian: 467.3–458.4 Ma
└Dapingian: 470.0–467.3 Ma
└ Early Ordovician: 485.4–470.0 Ma
├Floian: 477.7–470.0 Ma
└Tremadocian: 485.4–477.7 Ma
└ Cambrian Period: 539–485 Ma
├Furongian: 497–485.4 Ma
├Stage 10: 489.5–485.4 Ma
├Jiangshanian: 494–489.5 Ma
└Paibian: 497–494 Ma
├Miaolingian: 509–497 Ma
├Guzhangian: 500.5–497 Ma
├Drumian: 504.5–500.5 Ma
└Wuliuan: 509–504.5 Ma
├Series 2: 521–509 Ma
├Stage 4: 514–509 Ma
└Stage 3: 521–514 Ma
└ Terreneuvian: 539–521 Ma
├Stage 2: 529–521 Ma
└Fortunian: 539–529 Ma
├NeoProterozoic: 1,000–541 Ma
├Ediacaran: 635–541 Ma
├Cryogenian: 720–635 Ma
└Tonian: 1,000–720 Ma
├MesoProterozoic: 1.6–1.0 Ga
├Stenian: 1.2–1.0 Ga
├Ectasian: 1.4–1.2 Ga
└Calymmian: 1.6–1.4 Ga
└ PaleoProterozoic: 2.5–1.6 Ga
├Statherian: 1.8–1.6 Ga
├Orosirian: 2.1–1.8 Ga
├Rhyacian: 2.3–2.1 Ga
└Siderian: 2.5–2.3 Ga
├Archean: 4.0–2.5 Ga
├Neoarchean: 2.8–2.5 Ga
├Mesoarchean: 3.2–2.8 Ga
├Paleoarchean: 3.6–3.2 Ga
└ Eoarchean: 4.0–3.6 Ga
└ Hadean: 4.6–4.0 Ga
How is Geological Time organized?
Eons
The largest spanning time periods are Eons, which last for billions of years
Eras
Eras subdivide Eons and last for 100s of millions of years
Periods
Periods subdivide Eras and last 10s of millions of years
Epochs
Epochs subdivide Periods and last for millions of years
Ages
Ages subdivide Epochs and last 100s of thousands of years
Eons: billions of years (Ga)
└Eras: 100s of millions of years (Ma)
└Periods: 10s of millions of years (Ma)
└Epochs or Series: millions of years (Ma)
└Ages or Stages: 100s of thousands of years (Ka)
Below button goes to the official 2022 Geologic Time Scale from the International Strategic Commission
Click below to learn about major changes during Earth's history
