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| Segments of rock (strata) in chronostratigraphy | Periods of time in geochronology | Notes |
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4 total, half a billion years or more |
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12 total, several hundred million years |
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tens of millions of years |
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millions of years |
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smaller than an age/stage, not used by the ICS timescale |
It is also possible that the sea may have happened to flow little by little over the land consisting of both plain and mountain, and then have ebbed away from it.^"It is also possible that the sea may have happened to flow little by little over the land consisting of both plain and mountain, and then have ebbed away from it.
Geologic Time Scale 3 February 2010 15:51 UTC www.dailytemperaturecycle.com [Source type: FILTERED WITH BAYES]
^It is possible that each time the land was exposed by the ebbing of the sea a layer was left, since we see that some mountains appear to have been piled up layer by layer, and it is therefore likely that the clay from which they were formed was itself at one time arranged in layers.
Geologic Time Scale 3 February 2010 15:51 UTC www.dailytemperaturecycle.com [Source type: FILTERED WITH BAYES]
^Rip current: A current that flows strongly away from the sea shore through gaps in the surf zone at intervals along the shoreline.
Glossary of Geological Terms 17 January 2010 12:35 UTC www.geotech.org [Source type: FILTERED WITH BAYES]
... .It is possible that each time the land was exposed by the ebbing of the sea a layer was left, since we see that some mountains appear to have been piled up layer by layer, and it is therefore likely that the clay from which they were formed was itself at one time arranged in layers.^It is possible that each time the land was exposed by the ebbing of the sea a layer was left, since we see that some mountains appear to have been piled up layer by layer, and it is therefore likely that the clay from which they were formed was itself at one time arranged in layers.
Geologic Time Scale 3 February 2010 15:51 UTC www.dailytemperaturecycle.com [Source type: FILTERED WITH BAYES]
^Tyrannosaurs , Titanosaurs , duck bills , and horned dinosaurs ) evolve on land, as do Eusuchia ( modern crocodilians ); and mosasaurs and modern sharks appear in the sea.
Geologic Time Scale 3 February 2010 15:51 UTC www.dailytemperaturecycle.com [Source type: FILTERED WITH BAYES]
^In Namibia: 540 Ma: Rise of the Damara Granites, Moon Landscape Rocks , Rossing Mountain, Armour plated fish appear in the seas with the first shell fish.
Geological Time Scale Namibia 17 January 2010 12:35 UTC www.namibia-1on1.com [Source type: FILTERED WITH BAYES]
.One layer was formed first, then at a different period, a further was formed and piled, upon the first, and so on.^The evolving marine life of the Ordovician becomes even more diverse and this period records the first appearance of vertebrates in the form of ostracoderms, jawless, backboned fish.
Geological Background 3 February 2010 15:51 UTC uts.cc.utexas.edu [Source type: FILTERED WITH BAYES]
^As predicted by evolutionary theory Humans are similar to our closest cousins, chimpanzees and only differ by one amino acid to our further away cousins, the Rhesus monkeys.
Victoria Advocate | "Why We Shouldn't Teach Creationism" by Crobar 3 February 2010 15:51 UTC www.victoriaadvocate.com [Source type: Academic]
^Isotope: One of several forms of one element, all having the same number of protons in the nucleus, but differing in their number of neutrons and thus atomic weight.
Glossary of Geological Terms 17 January 2010 12:35 UTC www.geotech.org [Source type: FILTERED WITH BAYES]
.Over each layer there spread a substance of different material, which formed a partition between it and the next layer; but when petrification took place something occurred to the partition which caused it to break up and disintegrate from between the layers (possibly referring to unconformity).^Over each layer there spread a substance of different material, which formed a partition between it and the next layer; but when petrification took place something occurred to the partition which caused it to break up and disintegrate from between the layers (possibly referring to unconformity).
Geologic Time Scale 3 February 2010 15:51 UTC www.dailytemperaturecycle.com [Source type: FILTERED WITH BAYES]
^Duricrust A general term for a hard crust on or near the surface of a soil formed in a semi-arid climate and is made up of material such as calcrete and silcrete .
Glossary of Common Geoscience Terms - Geoscience Australia 17 January 2010 12:35 UTC www-a.ga.gov.au [Source type: FILTERED WITH BAYES]
^The presence of planktonic forms, aquatic macrophytes, and marsh plants indicates that deposition of the sediments took place in a body of water, probably a pond or lake.
The Geologic Column 17 January 2010 12:35 UTC www.detectingdesign.com [Source type: FILTERED WITH BAYES]
... .As to the beginning of the sea, its clay is either sedimentary or primeval, the latter not being sedimentary.^Sedimentary rocks are those that were formed at the Earths surface, either by accumulation and cementation of fragments of rocks, minerals, and organisms, or as precipitates from sea water, surface water or ground water.
GEOLOGY OF FLORIDA 3 February 2010 15:51 UTC www.clas.ufl.edu [Source type: FILTERED WITH BAYES]
.It is probable that the sedimentary clay was formed by the disintegration of the strata of mountains.^Shale A fine-grained sedimentary rock formed by the consolidation of clay or mud.
Glossary of Common Geoscience Terms - Geoscience Australia 17 January 2010 12:35 UTC www-a.ga.gov.au [Source type: FILTERED WITH BAYES]
Such is the formation of mountains.
| Supereon | Eon | Era | Period[19] | Epoch | Age[20] | Major events | Start, million years ago[20] |
|---|---|---|---|---|---|---|---|
| Phanerozoic | Cenozoic[21] | Quaternary | Holocene | Atlantic | .The last glacial period ends; rise of human civilization.^
^
^
.Quaternary Ice Age recedes, and the current interglacial begins.^
^
^
.Younger Dryas cold spell occurs, Sahara forms from savannah, and agriculture begins, allowing humans to build cities.^
.Paleolithic/Neolithic (Stone Age) cultures begin around 10000 BC, giving way to Copper Age (3500 BC) and Bronze Age (2500 BC).^
.Cultures continue to grow in complexity and technical advancement through the Iron Age (1200 BC), giving rise to many pre-historic cultures throughout the world, eventually leading into Classical Antiquity, such as the Roman Empire and even to the Middle Ages and present day.^
^
^
.Little Ice Age (stadial) causes brief cooling in Northern Hemisphere from 1400 to 1850. Also refer to the List of archaeological periods for clarification on early cultures and ages.^
^
^
.Mount Tambora erupts in 1815, causing the Year Without a Summer (1816) in Europe and North America from a volcanic winter.^
^
^
Atmospheric CO2 levels start creeping from 100 parts per million volume (ppmv) at the end of the last glaciation to the current level of 385 ppmv, causing global warming and climate change, most likely from anthropogenic sources, such as the Industrial Revolution[22] |
0.011430 ± 0.00013[21][23] | |
| Boreal | |||||||
| Pleistocene | Late/Tyrrhenian Stage/Eemian/Sangamonian | .Flourishing and then extinction of many large mammals (Pleistocene megafauna).^
.Evolution of anatomically modern humans.^
.Quaternary Ice Age continues with glaciations and interstadials (and the accompanying fluctuations from 100 to 300 ppmv in atmospheric CO2 levels[22]), further intensification of Icehouse Earth conditions, roughly 1.6 Ma.^
^
^
.Last glacial maximum (30000 years ago), last glacial period (18000–15000 years ago).^
^
^
.Dawn of human stone-age cultures, with increasing technical complexity relative to previous ice age cultures, such as engravings and clay statues (e.g.^
Venus of Lespugue), particularly in the Mediterranean and Europe. .Lake Toba supervolcano erupts 75000 years before present, causing a volcanic winter that pushes humanity to the brink of extinction.^
^
^
.Pleistocene ends with Oldest Dryas, Older Dryas/Allerød and Younger Dryas climate events, with Younger Dryas forming the boundary with the Holocene.^
^
|
0.126 ± 0.005* | ||||
| Middle | 0.500? | ||||||
| Early | 1.806 ± 0.005* | ||||||
| Gelasian | 2.588 ± 0.005* | ||||||
| Neogene | Pliocene | Piacenzian/Blancan | .Intensification of present Icehouse conditions, present (Quaternary) ice age begins roughly 2.58 Ma; cool and dry climate.^
^
^
.Australopithecines, many of the existing genera of mammals, and recent mollusks appear.^
.Homo habilis appears.^
|
3.600 ± 0.005* | |||
| Zanclean | 5.332 ± 0.005* | ||||||
| Miocene | Messinian | .Moderate Icehouse climate, puncuated by ice ages; Orogeny in northern hemisphere.^
^
^
Modern mammal and bird families became recognizable. .Horses and mastodons diverse.^
.Grasses become ubiquitous.^
.First apes appear (for reference see the article: "Sahelanthropus tchadensis").^
.Kaikoura Orogeny forms Southern Alps in New Zealand, continues today.^
^
^
Orogeny of the Alps in Europe slows, but continues to this day. .Carpathean orogeny forms Carpathian Mountains in Central and Eastern Europe.^
^
.Hellenic orogeny in Greece and Aegean Sea slows, but continues to this day.^
^
^
.Middle Miocene Disruption occurs.^
.Widespread forests slowly draw in massive amounts of CO2, gradually lowering the level of atmospheric CO2 from 650 ppmv down to around 100 ppmv[22].^
^
^
|
7.246 ± 0.05* | ||||
| Tortonian | 11.608 ± 0.05* | ||||||
| Serravallian | 13.65 ± 0.05* | ||||||
| Langhian | 15.97 ± 0.05* | ||||||
| Burdigalian | 20.43 ± 0.05* | ||||||
| Aquitanian | 23.03 ± 0.05* | ||||||
| Paleogene | Oligocene | Chattian | .Warm but cooling climate, moving towards Icehouse; Rapid evolution and diversification of fauna, especially mammals.^
^
^
Major evolution and dispersal of modern types of flowering plants |
28.4 ± 0.1* | |||
| Rupelian | 33.9 ± 0.1* | ||||||
| Eocene | Priabonian | .Moderate, cooling climate.^
Archaic mammals (e.g. .Creodonts, Condylarths, Uintatheres, etc) flourish and continue to develop during the epoch.^
^
.Appearance of several "modern" mammal families.^
^
.Primitive whales diversify.^
First grasses. .Reglaciation of Antarctica and formation of its ice cap; Azolla event triggers ice age, and the Icehouse Earth climate that would follow it to this day, from the settlement and decay of seafloor algae drawing in massive amounts of atmospheric carbon dioxide[22], lowering it from 3800 ppmv down to 650 ppmv.^
^
^
.End of Laramide and Sevier Orogenies of the Rocky Mountains in North America.^
^
^
.Orogeny of the Alps in Europe begins.^
^
^
.Hellenic Orogeny begins in Greece and Aegean Sea.^
^
|
37.2 ± 0.1* | ||||
| Bartonian | 40.4 ± 0.2* | ||||||
| Lutetian | 48.6 ± 0.2* | ||||||
| Ypresian | 55.8 ± 0.2* | ||||||
| Paleocene | Thanetian | Climate tropical. .Modern plants appear; Mammals diversify into a number of primitive lineages following the extinction of the dinosaurs.^
^
.First large mammals (up to bear or small hippo size).^
Alpine orogeny in Europe and Asia begins. .Indian Subcontinent collides with Asia 55 Ma, Himalayan Orogeny starts between 52 and 48 Ma.^
^
^
|
58.7 ± 0.2* | ||||
| Selandian | 61.7 ± 0.3* | ||||||
| Danian | 65.5 ± 0.3* | ||||||
| Mesozoic | Cretaceous | Late | Maastrichtian | .Flowering plants proliferate, along with new types of insects.^
^
.More modern teleost fish begin to appear.^
^
.Ammonites, belemnites, rudist bivalves, echinoids and sponges all common.^
^
.Many new types of dinosaurs (e.g.^
^
^
.Tyrannosaurs, Titanosaurs, duck bills, and horned dinosaurs) evolve on land, as do Eusuchia (modern crocodilians); and mosasaurs and modern sharks appear in the sea.^
^
.Primitive birds gradually replace pterosaurs.^
.Monotremes, marsupials and placental mammals appear.^
.Break up of Gondwana.^
.Beginning of Laramide and Sevier Orogenies of the Rocky Mountains.^
^
^
.Atmospheric CO2 close to present-day levels.^
^
^
|
70.6 ± 0.6* | ||
| Campanian | 83.5 ± 0.7* | ||||||
| Santonian | 85.8 ± 0.7* | ||||||
| Coniacian | 89.3 ± 1.0* | ||||||
| Turonian | 93.5 ± 0.8* | ||||||
| Cenomanian | 99.6 ± 0.9* | ||||||
| Early | Albian | 112.0 ± 1.0* | |||||
| Aptian | 125.0 ± 1.0* | ||||||
| Barremian | 130.0 ± 1.5* | ||||||
| Hauterivian | 136.4 ± 2.0* | ||||||
| Valanginian | 140.2 ± 3.0* | ||||||
| Berriasian | 145.5 ± 4.0* | ||||||
| Jurassic | Late | Tithonian | Gymnosperms (especially conifers, Bennettitales and cycads) and ferns common. Many types of dinosaurs, such as sauropods, carnosaurs, and stegosaurs. Mammals common but small. First birds and lizards. Ichthyosaurs and plesiosaurs diverse. Bivalves, Ammonites and belemnites abundant. Sea urchins very common, along with crinoids, starfish, sponges, and terebratulid and rhynchonellid brachiopods. Breakup of Pangaea into Gondwana and Laurasia. Nevadan orogeny in North America. Rantigata and Cimmerian Orogenies taper off. .Atmospheric CO2 levels 4-5 times the present day levels (1200-1500 ppmv, compared to today's 385 ppmv[22]).^
^
^
|
150.8 ± 4.0* | |||
| Kimmeridgian | 155.7 ± 4.0* | ||||||
| Oxfordian | 161.2 ± 4.0* | ||||||
| Middle | Callovian | 164.7 ± 4.0 | |||||
| Bathonian | 167.7 ± 3.5* | ||||||
| Bajocian | 171.6 ± 3.0* | ||||||
| Aalenian | 175.6 ± 2.0* | ||||||
| Early | Toarcian | 183.0 ± 1.5* | |||||
| Pliensbachian | 189.6 ± 1.5* | ||||||
| Sinemurian | 196.5 ± 1.0* | ||||||
| Hettangian | 199.6 ± 0.6* | ||||||
| Triassic | Late | Rhaetian | Archosaurs dominant on land as dinosaurs, in the oceans as Ichthyosaurs and nothosaurs, and in the air as pterosaurs. .Cynodonts become smaller and more mammal-like, while first mammals and crocodilia appear.^
^
Dicrodium flora common on land. Many large aquatic temnospondyl amphibians. Ceratitic ammonoids extremely common. Modern corals and teleost fish appear, as do many modern insect clades. Andean Orogeny in South America. Cimmerian Orogeny in Asia. Rangitata Orogeny begins in New Zealand. .Hunter-Bowen Orogeny in Northern Australia, Queensland and New South Wales ends, (c.^
260-225 Ma) |
203.6 ± 1.5* | |||
| Norian | 216.5 ± 2.0* | ||||||
| Carnian | 228.0 ± 2.0* | ||||||
| Middle | Ladinian | 237.0 ± 2.0* | |||||
| Anisian | 245.0 ± 1.5* | ||||||
| Early | Olenekian | 249.7 ± 1.5* | |||||
| Induan | 251.0 ± 0.7* | ||||||
| Paleozoic | Permian | Lopingian | Changhsingian | Landmasses unite into supercontinent Pangaea, creating the Appalachians. End of Permo-Carboniferous glaciation. Synapsid reptiles (pelycosaurs and therapsids) become plentiful, while parareptiles and temnospondyl amphibians remain common. .In the mid-Permian, coal-age flora are replaced by cone-bearing gymnosperms (the first true seed plants) and by the first true mosses.^
Beetles and flies evolve. .Marine life flourishes in warm shallow reefs; productid and spiriferid brachiopods, bivalves, forams, and ammonoids all abundant.^
^
.Permian-Triassic extinction event occurs 251 Ma: 95% of life on Earth becomes extinct, including all trilobites, graptolites, and blastoids.^
^
^
Ouachita and Innuitian orogenies in North America. Uralian orogeny in Europe/Asia tapers off. Altaid orogeny in Asia. Hunter-Bowen Orogeny on Australian Continent begins (c. 260-225 Ma), forming the MacDonnell Ranges. |
253.8 ± 0.7* | ||
| Wuchiapingian | 260.4 ± 0.7* | ||||||
| Guadalupian | Capitanian | 265.8 ± 0.7* | |||||
| Wordian/Kazanian | 268.4 ± 0.7* | ||||||
| Roadian/Ufimian | 270.6 ± 0.7* | ||||||
| Cisuralian | Kungurian | 275.6 ± 0.7* | |||||
| Artinskian | 284.4 ± 0.7* | ||||||
| Sakmarian | 294.6 ± 0.8* | ||||||
| Asselian | 299.0 ± 0.8* | ||||||
| Carbon- iferous[24]/ Pennsyl- vanian |
Late | Gzhelian | Winged insects radiate suddenly; some (esp. Protodonata and Palaeodictyoptera) are quite large. Amphibians common and diverse. First reptiles and coal forests (scale trees, ferns, club trees, giant horsetails, Cordaites, etc.). .Highest-ever atmospheric oxygen levels.^
Goniatites, brachiopods, bryozoa, bivalves, and corals plentiful in the seas and oceans. Testate forams proliferate. Uralian orogeny in Europe and Asia. Variscan orogeny occurs towards middle and late Mississippian Periods. |
303.9 ± 0.9* | |||
| Kasimovian | 306.5 ± 1.0* | ||||||
| Middle | Moscovian | 311.7 ± 1.1* | |||||
| Early | Bashkirian | 318.1 ± 1.3* | |||||
| Carbon- iferous[24]/ Missis- sippian |
Late | Serpukhovian | .Large primitive trees, first land vertebrates, and amphibious sea-scorpions live amid coal-forming coastal swamps.^
^
^
Lobe-finned rhizodonts are dominant big fresh-water predators. In the oceans, early sharks are common and quite diverse; echinoderms (especially crinoids and blastoids) abundant. Corals, bryozoa, goniatites and brachiopods (Productida, Spiriferida, etc.) very common, but trilobites and nautiloids decline. Glaciation in East Gondwana. Tuhua Orogeny in New Zealand tapers off. |
326.4 ± 1.6* | |||
| Middle | Viséan | 345.3 ± 2.1* | |||||
| Early | Tournaisian | 359.2 ± 2.5* | |||||
| Devonian | Late | Famennian | .First clubmosses, horsetails and ferns appear, as do the first seed-bearing plants (progymnosperms), first trees (the progymnosperm Archaeopteris), and first (wingless) insects.^
^
^
.Strophomenid and atrypid brachiopods, rugose and tabulate corals, and crinoids are all abundant in the oceans.^
Goniatite ammonoids are plentiful, while squid-like coleoids arise. .Trilobites and armoured agnaths decline, while jawed fishes (placoderms, lobe-finned and ray-finned fish, and early sharks) rule the seas.^
^
^
First amphibians still aquatic. "Old Red Continent" of Euramerica. .Beginning of Acadian Orogeny for Anti-Atlas Mountains of North Africa, and Appalachian Mountains of North America, also the Antler, Variscan, and Tuhua Orogeny in New Zealand.^
|
374.5 ± 2.6* | |||
| Frasnian | 385.3 ± 2.6* | ||||||
| Middle | Givetian | 391.8 ± 2.7* | |||||
| Eifelian | 397.5 ± 2.7* | ||||||
| Early | Emsian | 407.0 ± 2.8* | |||||
| Pragian | 411.2 ± 2.8* | ||||||
| Lochkovian | 416.0 ± 2.8* | ||||||
| Silurian | Pridoli | no faunal stages defined | .First Vascular plants (the rhyniophytes and their relatives), first millipedes and arthropleurids on land.^
.First jawed fishes, as well as many armoured jawless fish, populate the seas.^
^
Sea-scorpions reach large size. .Tabulate and rugose corals, brachiopods (Pentamerida, Rhynchonellida, etc.^
), and crinoids all abundant. Trilobites and mollusks diverse; graptolites not as varied. Beginning of Caledonian Orogeny for hills in England, Ireland, Wales, Scotland, and the Scandinavian Mountains. Also continued into Devonian period as the Acadian Orogeny, above. Taconic Orogeny tapers off. Lachlan Orogeny on Australian Continent tapers off. |
418.7 ± 2.7* | |||
| Ludlow/Cayugan | Ludfordian | 421.3 ± 2.6* | |||||
| Gorstian | 422.9 ± 2.5* | ||||||
| Wenlock | Homerian/Lockportian | 426.2 ± 2.4* | |||||
| Sheinwoodian/Tonawandan | 428.2 ± 2.3* | ||||||
| Llandovery/ Alexandrian |
Telychian/Ontarian | 436.0 ± 1.9* | |||||
| Aeronian | 439.0 ± 1.8* | ||||||
| Rhuddanian | 443.7 ± 1.5* | ||||||
| Ordovician | Late | Hirnantian | Invertebrates diversify into many new types (e.g., long straight-shelled cephalopods). Early corals, articulate brachiopods (Orthida, Strophomenida, etc.), .bivalves, nautiloids, trilobites, ostracods, bryozoa, many types of echinoderms (crinoids, cystoids, starfish, etc.^
), branched .graptolites, and other taxa all common.^
Conodonts (early planktonic vertebrates) appear. First green plants and fungi on land. .Ice age at end of period.^
^
^
|
445.6 ± 1.5* | |||
| other faunal stages | 460.9 ± 1.6* | ||||||
| Middle | Darriwilian | 468.1 ± 1.6* | |||||
| other faunal stages | 471.8 ± 1.6* | ||||||
| Early | Arenig | 478.6 ± 1.7* | |||||
| Tremadocian | 488.3 ± 1.7* | ||||||
| Cambrian | Furongian | other faunal stages | Major diversification of life in the Cambrian Explosion. .Many fossils; most modern animal phyla appear.^
^
.First chordates appear, along with a number of extinct, problematic phyla.^
Reef-building Archaeocyatha abundant; then vanish. .Trilobites, priapulid worms, sponges, inarticulate brachiopods (unhinged lampshells), and many other animals numerous.^
^
Anomalocarids are giant predators, while many Ediacaran fauna die out. .Prokaryotes, protists (e.g., forams), fungi and algae continue to present day.^
Gondwana emerges. Petermann Orogeny on the Australian Continent tapers off (550-535 Ma). Ross Orogeny in Antarctica. Adelaide Geosyncline (Delamerian Orogeny), majority of orogenic activity from 514-500 Ma. Lachlan Orogeny on Australian Continent, c. 540-440 Ma. Atmospheric CO2 content roughly 20-35 times present-day (Holocene) levels (6000 ppmv compared to today's 385 ppmv)[22] |
496.0 ± 2.0* | |||
| Paibian/Ibexian/ Ayusokkanian/Sakian/ Aksayan |
501.0 ± 2.0* | ||||||
| Middle | other faunal stages/Albertan | 513.0 ± 2.0 | |||||
| Early | other faunal stages/ Waucoban/Tommotian/ Atdabanian/Botomian |
542.0 ± 1.0* | |||||
| Precam- brian[25] |
Proter- ozoic[26] |
Neo- proterozoic[26] |
Ediacaran | Good fossils of the first multi-celled animals. Ediacaran biota flourish worldwide in seas. Simple trace fossils of possible worm-like Trichophycus, etc. First sponges and trilobitomorphs. .Enigmatic forms include many soft-jellied creatures shaped like bags, disks, or quilts (like Dickinsonia).^
^
^
Taconic Orogeny in North America. Aravalli Range orogeny in Indian Subcontinent. Beginning of Petermann Orogeny on Australian Continent. Beardmore Orogeny in Antarctica, 633-620 Ma. |
630 +5/-30* | ||
| Cryogenian | Possible "Snowball Earth" period. Fossils still rare. Rodinia landmass begins to break up. Late Ruker / Nimrod Orogeny in Antarctica tapers off. | 850[27] | |||||
| Tonian | Rodinia supercontinent persists. Trace fossils of simple multi-celled eukaryotes. First radiation of dinoflagellate-like acritarchs. .Grenville Orogeny tapers off in North America.^
Pan-African orogeny in Africa. Lake Ruker / Nimrod Orogeny in Antarctica, 1000 ± 150 Ma. Edmundian Orogeny (c. 920 - 850 Ma), Gascoyne Complex, Western Australia. Adelaide Geosyncline laid down on Australian Continent, beginning of Adelaide Geosyncline (Delamerian Orogeny) in that continent. |
1000[27] | |||||
| Meso- proterozoic[26] |
Stenian | Narrow highly metamorphic belts due to orogeny as Rodinia formed. Late Ruker / Nimrod Orogeny in Antarctica possibly begins. Musgrave Orogeny (c. 1080 Ma), Musgrave Block, Central Australia. | 1200[27] | ||||
| Ectasian | Platform covers continue to expand. Green algae colonies in the seas. Grenville Orogeny in North America. | 1400[27] | |||||
| Calymmian | Platform covers expand. Barramundi Orogeny, MacArthur Basin, Northern Australia, and Isan Orogeny, c. 1600 Ma, Mount Isa Block, Queensland | 1600[27] | |||||
| Paleo- proterozoic[26] |
Statherian | First complex single-celled life: protists with nuclei. Columbia is the primordial supercontinent. Kimban Orogeny in Australian Continent ends. Yapungku Orogeny on North Yilgarn craton, in Western Australia. Mangaroon Orogeny, 1680-1620 Ma, on the Gascoyne Complex in Western Australia. Kararan Orogeny (1650- Ma), Gawler Craton, South Australia. | 1800[27] | ||||
| Orosirian | The atmosphere became oxygenic. Vredefort and Sudbury Basin asteroid impacts. Much orogeny. Penokean and Trans-Hudsonian Orogenies in North America. Early Ruker Orogeny in Antarctica, 2000 - 1700 Ma. Glenburgh Orogeny, Glenburgh Terrane, Australian Continent c. 2005 - 1920 Ma. Kimban Orogeny, Gawler craton in Australian Continent begins. | 2050[27] | |||||
| Rhyacian | Bushveld Formation formed. Huronian glaciation. | 2300[27] | |||||
| Siderian | .Oxygen catastrophe: banded iron formations formed.^
^
^
Sleaford Orogeny on Australian Continent, Gawler Craton 2440-2420 Ma. |
2500[27] | |||||
| Archean[26] | Neoarchean[26] | Stabilization of most modern cratons; possible mantle overturn event. Insell Orogeny, 2650 ± 150 Ma. .Abitibi greenstone belt in present-day Ontario and Quebec begins to form, stablizes by 2600 Ma.^
^
|
2800[27] | ||||
| Mesoarchean[26] | First stromatolites (probably colonial cyanobacteria). Oldest macrofossils. Humboldt Orogeny in Antarctica. .Blake River Megacaldera Complex begins to form in present-day Ontario and Quebec, ends by roughly 2696 Ma.^
^
^
|
3200[27] | |||||
| Paleoarchean[26] | First known oxygen-producing bacteria. Oldest definitive microfossils. .Oldest cratons on earth (such as the Canadian Shield and the Pilbara Craton) may have formed during this period[28].^
^
^
Rayner Orogeny in Antarctica. |
3600[27] | |||||
| Eoarchean[26] | .Simple single-celled life (probably bacteria and perhaps archaea).^
Oldest probable microfossils. |
3800 | |||||
| Hadean [26][29] |
Early Imbrian[26][30] | This era overlaps the end of the Late Heavy Bombardment of the inner solar system. | c.3850 | ||||
| Nectarian[26][30] | .This unit gets its name from the lunar geologic timescale when the Nectaris Basin and other major lunar basins were formed by large impact events.^
^
^
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c.3920 | |||||
| Basin Groups[26][30] | Oldest known rock (4030 Ma)[31]. .The first Lifeforms and self-replicating RNA molecules may have evolved on earth around 4000 Ma during this era.^
^
^
Napier Orogeny in Antarctica, 4000 ± 200 Ma. |
c.4150 | |||||
| Cryptic[26][30] | Oldest known mineral (Zircon, 4406±8 Ma[32]). Formation of Moon (4533 Ma), probably from giant impact. Formation of Earth (4567.17 to 4570 Ma) | c.4570 | |||||
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Here are sentences from other pages on Geologic time scale, which are similar to those in the above article.
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