Geologic Time Scale

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I'm currently reading Thomas Halliday's Otherlands about the history of life on earth. There is a little table of eons, eras, periods and epochs at the beginning of the book, but it only contains names and dates. To get some more orientation, I went over to Wikipedia's Geological time scale article and fell down a bit of a rabbit hole, following links and collecting bits of information. The result is the following table with copy-pasted facts that seemed familiar or interesting to me, sorted into epochs and periods. All times are given in millions of years. Disclaimer: the selection of included facts is arbitrary and probably there are some inaccuracies.

Reasonably wide display strongly recommended!

Eon Era Period Epoch Start Description
Phanerozoic Cenozoic Quaternary Holocene 0.0117 Glacial retreat. Rapid rise of human species.
Pleistocene 2.58 Ice Age, repeated glaciations resulting in lower sea levels (> 100m) → Bering land bridge (Beringian refugium). *† Homo erectus, * Homo sapience (0.3).
Neogene Pliocene 5.333 Appearance of Homo (2.6), genus including modern humans. Formation of Isthmus of Panama, linking North and South America → Great American Interchange → end of some indigenous South American animals. Strait of Gibraltar opened (5.333) and Mediterranean refilled (Zanclean flood). Beringia first flooded.
Miocene 23.03 Collision of Arabian Peninsula with Eurasia cut off Mediterranean from Indian Ocean and connection between Atlantic and Mediterranean closed → Mediterranean nearly dried up (Messinian salinity crisis).
Palaeogene Oligocene 33.9 Replacement of European fauna with Asian fauna (Grande Coupure). Global expansion of grasslands, regression of tropical broad leaf forests to equatorial belt.
Eocene 56 Concentration of 13C in atmosphere exceptionally low at start. Forests cover most of the Earth, including poles (palm trees in Alaska and northern Europe). First fossils of most modern mammals.
Paleocene 66 Starts with Chicxulub impact and K-Pg extinction (66): † 75% of all species, among them all non-avian dinosaurs.
Mesozoic Cretaceous 145 Breakup of Gondwana accelerates: South America, Antarctica and Australia rifted away from Africa, South Atlantic and Indian Oceans newly formed. Warm climate, high sea levels. Large areas of continents covered by warm, shallow seas → marine limestone deposits from calcite skeletons of algae (chalk, white cliffs of Dover, Rügen). Stagnation of deep sea currents → anoxic conditions → deposited organic matter undecomposed (half of world's petroleum reserves in today's Persian Gulf and Gulf of Mexico). Formation of dark anoxic shales → source rock for oil and gas. First fossils of grasses. Most diverse stage of dinosaurs.
Jurassic 201.3 Gondwana breakup begins. Toarcian Oceanic Anoxic Event (TOAE, aka Jenkyns Event): widespread oceanic anoxia → deposition of black shales → largest oil reserves (North Sea, Saudi Arabia, Iraq); Sichuan Basin transformed into giant lake → sequestered large amounts of carbon. Ginkgoales more diverse than today, widespread in Eurasia. Dinosaurs become dominant vertebrates in terrestrial ecosystems after end-Triassic extinction. First birds evolve from dinosaurs; first lizards, sharks, rays, crabs.
Triassic 251.9 Interior: Hot and dry continental climate. Polar regions: moist and temperate, suitable for forests and vertebrates. * First archosaurs (ancestors of birds and crocodilians), dinosaurs (subgroup of archosaurs), modern corals, modern amphibians. Triassic-Jurassic extinction (201.3): † 70-75% of all species. Pangaea begins breaking up into Gondwana and Laurasia (200).
Paleozoic Permian 298.9 Vast deserts within Pangea after Carboniferous rainforest collapse. 3-4 extinction events, last: Permian-Triassic extinction (252): † 90-96% of all species (largest in Earth's history).
Carboniferous 358.9 coal-bearing: many coal beds formed globally from vast forests. Age of amphibians: amphibians dominant land vertebrates, diversified into many forms (lizard-like, snake-like, crocodile-like). Later glaciations, low sea level, mountain building as continents collided to form Pangaea. Minor extinction event: Carboniferous rainforest collapse.
Devonian 419.2 First significant adaptive radiation of life on dry land. Extensive forests, leaves and roots evolved, first seed-bearing pants. Age of fishes: substantial diversity. First ammonites. Late Devonion extinction (375-360): † 70% of all species.
Silurian 443.8 First megafossils (visible without microscope) of extensive terrestrial biota: moss-like miniature forests. First fossil records of vascular plants (land plants with tissues carrying water and food). First bony fish, development of movable jaws in fish. First animals fully adapted to terrestrial conditions.
Ordovician 485.4 Ordovician radiation: great biodiversification. Molluscs and arthropods dominate oceans; the latter start their establishment on land. First land plants. Ordovician-Silurian extinction events (450-440): † 85% of all species.
Cambrian 541 Cambrian explosion: rapid diversification of lifeforms, first representatives of all modern animal phyla, spread of animals with mineral skeletons and shells → better fossil record. First vertebrates.
Proterozoic Neoproterozoic Ediacaran 635 Avalon explosion (575): * widespread multicellular fauna after Snowball Earth glaciation events, most of which † during End-Ediacaran extinction event (539). Last stage of formation of supercontinent Gondwana.
Cryogenian 720 Earth's surface possibly (almost) entirely frozen (Snowball Earth hypothesis). First uncontroversial animal fossils (rare).
Tonian 1000 Breakup of Rodinia (900-850). First hypothetical animals.
Mesoproterozoic Stenian 1200 Supercontinent Rodinia assembled. * Fossils of oldest sexually reproducing organism (type of red algae, sometimes dated to Ectasian).
Ectasian 1400 Continued expansion of platform covers. More complex microfossils, also found on land, fungus-like organisms and microbes.
Calymmian 1600 Supercontinent Columbia starts to break (1500). Expansion of existing platform covers (sedimentary strata, which overlie basement of rocks of earlier deformation), new platforms.
Paleoproterozoic Statherian 1800 Supercontinent Columbia has assembled. New platforms or final cratonization of fold belts. Oxygen levels 10% to 20% of current values. First fossil records of eukaryotes
Orosirian 2050 Intense orogeny (formation of mountains by collision of tectonic plates) on all continents: Asteroid collisions: Vredefort impact structure (2023), Sudbury Basin structure (1850).
Rhyacian 2300 Huronian global glaciation begins. First record of multicellular life (Francevillian biota, aka Gabon macrofossils, 2100). Probably first eukaryotes (organism with cells that have nucleus enclosed in nuclear envelope).
Siderian 2500 Deposition of banded iron formations peaked when iron rich formations formed as cyanobacteria produced waste oxygen → iron oxide. Removed iron from Earth's oceans, turning greenish seas clear. Without iron, oceans no longer oxygen sink, allowing buildup of oxygen-rich atmosphere, which triggered oxygen catastrophe: oxygen in atmosphere → † anaerobic species on Earth. May have triggered Huronian glaciation.