geologic time scale

aesthetics  →
being  →
complexity  →
database  →
enterprise  →
ethics  →
fiction  →
history  →
internet  →
knowledge  →
language  →
licensing  →
linux  →
logic  →
method  →
news  →
perception  →
philosophy  →
policy  →
purpose  →
religion  →
science  →
sociology  →
software  →
truth  →
unix  →
wiki  →
essay  →
feed  →
help  →
system  →
wiki  →
critical  →
discussion  →
forked  →
imported  →
original  →
geologic time scale
[ temporary import ]
please note:
- the content below is remote from Wikipedia
- it has been imported raw for GetWiki
{{short description|System that relates geological strata to time}}{{Use dmy dates|date=July 2016}}File:Geologic Clock with events and periods.svg|thumb|400px|This clock representation shows some of the major units of geological time and definitive events of Earth history. The Hadean eon represents the time before fossil record of life on Earth; its upper boundary is now regarded as 4.0 Ga (billion years ago). Other subdivisions reflect the evolution of life; the Archean and Proterozoic are both eons, the Palaeozoic, Mesozoic and Cenozoic are eras of the Phanerozoic eon. The three million year QuaternaryQuaternaryThe geologic time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history. The table of geologic time spans, presented here, agree with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy (ICS).__TOC__{{clear}}


The primary defined divisions of time are eons, in sequence the Hadean, the Archean, the Proterozoic and the Phanerozoic.The first three of these can be referred to collectively as the Precambrian supereon. Eons are divided into eras, which are in turn divided into periods, epochs and ages.{{Timeline geological timescale}}Corresponding to eons, eras, periods, epochs and ages, the terms "eonothem", "erathem", "system", "series", "stage" are used to refer to the layers of rock that belong to these stretches of geologic time in Earth's history.Geologists qualify these units as "early", "mid", and "late" when referring to time, and "lower", "middle", and "upper" when referring to the corresponding rocks. For example, the lower Jurassic Series in chronostratigraphy corresponds to the early Jurassic Epoch in geochronology.WEB, International Commission on Stratigraphy, Chronostratigraphic Units, International Stratigraphic Guide, 14 December 2009,weblink yes,weblink" title="">weblink 9 December 2009, dmy-all, The adjectives are capitalized when the subdivision is formally recognized, and lower case when not; thus "early Miocene" but "Early Jurassic."


Evidence from radiometric dating indicates that Earth is about 4.54 billion years old.WEB
, 1997, Age of the Earth
, U.S. Geological Survey
, 2006-01-10! Supereon! Eon ! Era! Period{{efn|Paleontologists often refer to faunal stages rather than geologic (geological) periods. The stage nomenclature is quite complex. For a time-ordered list of faunal stages, see.WEB,weblink The Paleobiology Database, 2006-03-19, yes,weblink" title="">weblink 11 February 2006, dmy, }}! Epoch! Age{{efn|name="uncertain-dates"}}! Major events! Start, million years ago{{efn|name="uncertain-dates"|Dates are slightly uncertain with differences of a few percent between various sources being common. This is largely due to uncertainties in radiometric dating and the problem that deposits suitable for radiometric dating seldom occur exactly at the places in the geologic column where they would be most useful. The dates and errors quoted above are according to the International Commission on Stratigraphy 2015 time scale except the Hadean eon. Where errors are not quoted, errors are less than the precision of the age given.* indicates boundaries where a Global Boundary Stratotype Section and Point has been internationally agreed upon.}}
weblink" title="">weblink> archivedate= 23 December 2005, no, JOURNAL
, Dalrymple, G. Brent
, The age of the Earth in the twentieth century: a problem (mostly) solved, Special Publications, Geological Society of London
, 2001, 190
, 1, 205–221
, 10.1144/GSL.SP.2001.190.01.14, 2001GSLSP.190..205D,
The geology or deep time of Earth's past has been organized into various units according to events which took place. Different spans of time on the GTS are usually marked by corresponding changes in the composition of strata which indicate major geological or paleontological events, such as mass extinctions. For example, the boundary between the Cretaceous period and the Paleogene period is defined by the Cretaceous–Paleogene extinction event, which marked the demise of the non-avian dinosaurs and many other groups of life. Older time spans, which predate the reliable fossil record (before the Proterozoic eon), are defined by their absolute age.
Geologic units from the same time but different parts of the world often look different and contain different fossils, so the same time-span was historically given different names in different locales. For example, in North America, the Lower Cambrian is called the Waucoban series that is then subdivided into zones based on succession of trilobites. In East Asia and Siberia, the same unit is split into Alexian, Atdabanian, and Botomian stages. A key aspect of the work of the International Commission on Stratigraphy is to reconcile this conflicting terminology and define universal horizons that can be used around the world.WEB,weblink Statutes of the International Commission on Stratigraphy, 26 November 2009, Some other planets and moons in the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus, Mars and the Earth's Moon. Dominantly fluid planets, such as the gas giants, do not preserve their history in a comparable manner. Apart from the Late Heavy Bombardment, events on other planets probably had little direct influence on the Earth, and events on Earth had correspondingly little effect on those planets. Construction of a time scale that links the planets is, therefore, of only limited relevance to the Earth's time scale, except in a Solar System context. The existence, timing, and terrestrial effects of the Late Heavy Bombardment are still debated.{{efn|Not enough is known about extra-solar planets for worthwhile speculation.}}

History and nomenclature of the time scale

{{Life timeline}}(File:Geological time spiral.png|thumb|Graphical representation of Earth's history as a spiral)

Early history

In Ancient Greece, Aristotle (384-322 BCE) observed that fossils of seashells in rocks resembled those found on beaches – he inferred that the fossils in rocks were formed by organisms, and he reasoned that the positions of land and sea had changed over long periods of time. Leonardo da Vinci (1452–1519) concurred with Aristotle's interpretation that fossils represented the remains of ancient life.WEB,weblink Correlating Earth's History, Paul R., Janke, Worldwide Museum of Natural History, 1999, The 11th-century Persian polymath Avicenna (Ibn Sina, died 1037) and the 13th-century Dominican bishop Albertus Magnus (died 1280) extended Aristotle's explanation into a theory of a petrifying fluid.BOOK, The Meaning of Fossils: Episodes in the History of Palaeontology, M. J. S., Rudwick, 1985, University of Chicago Press, 978-0-226-73103-2, 24, Avicenna also first proposed one of the principles underlying geologic time scales, the law of superposition of strata, while discussing the origins of mountains in The Book of Healing (1027).JOURNAL, 10.1111/j.1365-3091.2008.01009.x, The role of the Mediterranean region in the development of sedimentary geology: A historical overview, 2009, Fischer, Alfred G., Garrison, Robert E., Sedimentology, 56, 1, 3, 2009Sedim..56....3F, WEB,weblink The contribution of Ibn Sina (Avicenna) to the development of the Earth Sciences, The Chinese naturalist Shen Kuo (1031–1095) also recognized the concept of "deep time".SIVIN > FIRST = NATHAN, Nathan Sivin, Science in Ancient China: Researches and Reflections, Ashgate Publishing Variorum series
location = Brookfield, Vermont nopp = true,

Establishment of primary principles

In the late 17th century Nicholas Steno (1638–1686) pronounced the principles underlying geologic (geological) time scales. Steno argued that rock layers (or strata) were laid down in succession, and that each represents a "slice" of time. He also formulated the law of superposition, which states that any given stratum is probably older than those above it and younger than those below it. While Steno's principles were simple, applying them proved challenging. Steno's ideas also lead to other important concepts geologists use today, such as relative dating. Over the course of the 18th century geologists realized that:
  1. Sequences of strata often become eroded, distorted, tilted, or even inverted after deposition
  2. Strata laid down at the same time in different areas could have entirely different appearances
  3. The strata of any given area represented only part of Earth's long history
The Neptunist theories popular at this time (expounded by Abraham Werner (1749–1817) in the late 18th century) proposed that all rocks had precipitated out of a single enormous flood. A major shift in thinking came when James Hutton presented his Theory of the Earth; or, an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the GlobeJOURNAL, Hutton, James, James Hutton, Theory of the Earth; or an investigation of the laws observable in the composition, dissolution, and restoration of land upon the Globe,weblink Transactions of the Royal Society of Edinburgh, 1788, 1, 2, 209–308, 2016-09-06, 10.1017/s0080456800029227, 2013, before the Royal Society of Edinburgh in March and April 1785. John McPhee asserts that "as things appear from the perspective of the 20th century, James Hutton in those readings became the founder of modern geology".BOOK, John, McPhee, John McPhee, Basin and Range, New York, Farrar, Straus and Giroux, 1981, {{rp|95–100}}Hutton proposed that the interior of Earth was hot, and that this heat was the engine which drove the creation of new rock: land was eroded by air and water and deposited as layers in the sea; heat then consolidated the sediment into stone, and uplifted it into new lands. This theory, known as "Plutonism", stood in contrast to the "Neptunist" flood-oriented theory.

Formulation of geologic time scale

The first serious attempts to formulate a geologic time scale that could be applied anywhere on Earth were made in the late 18th century. The most influential of those early attempts (championed by Werner, among others) divided the rocks of Earth's crust into four types: Primary, Secondary, Tertiary, and Quaternary. Each type of rock, according to the theory, formed during a specific period in Earth history. It was thus possible to speak of a "Tertiary Period" as well as of "Tertiary Rocks." Indeed, "Tertiary" (now Paleogene and Neogene) remained in use as the name of a geological period well into the 20th century and "Quaternary" remains in formal use as the name of the current period.The identification of strata by the fossils they contained, pioneered by William Smith, Georges Cuvier, Jean d'Omalius d'Halloy, and Alexandre Brongniart in the early 19th century, enabled geologists to divide Earth history more precisely. It also enabled them to correlate strata across national (or even continental) boundaries. If two strata (however distant in space or different in composition) contained the same fossils, chances were good that they had been laid down at the same time. Detailed studies between 1820 and 1850 of the strata and fossils of Europe produced the sequence of geologic periods still used today.

Naming of geologic periods, eras and epochs

Early work on developing the geologic time scale was dominated by British geologists, and the names of the geologic periods reflect that dominance. The "Cambrian", (the classical name for Wales) and the "Ordovician", and "Silurian", named after ancient Welsh tribes, were periods defined using stratigraphic sequences from Wales.{{rp|113–114}} The "Devonian" was named for the English county of Devon, and the name "Carboniferous" was an adaptation of "the Coal Measures", the old British geologists' term for the same set of strata. The "Permian" was named after Perm, Russia, because it was defined using strata in that region by Scottish geologist Roderick Murchison. However, some periods were defined by geologists from other countries. The "Triassic" was named in 1834 by a German geologist Friedrich Von Alberti from the three distinct layers (Latin meaning triad)—red beds, capped by chalk, followed by black shales—that are found throughout Germany and Northwest Europe, called the ‘Trias’. The "Jurassic" was named by a French geologist Alexandre Brongniart for the extensive marine limestone exposures of the Jura Mountains. The "Cretaceous" (from Latin creta meaning ‘chalk’) as a separate period was first defined by Belgian geologist Jean d'Omalius d'Halloy in 1822, using strata in the Paris basinENCYCLOPEDIA, Great Soviet Encyclopedia, Sovetskaya Enciklopediya, 3rd, vol. 16, p. 50, 1974, Moscow, Russian, true, Great Soviet Encyclopedia, and named for the extensive beds of chalk (calcium carbonate deposited by the shells of marine invertebrates) found in Western Europe.British geologists were also responsible for the grouping of periods into eras and the subdivision of the Tertiary and Quaternary periods into epochs. In 1841 John Phillips published the first global geologic time scale based on the types of fossils found in each era. Phillips' scale helped standardize the use of terms like Paleozoic ("old life") which he extended to cover a larger period than it had in previous usage, and Mesozoic ("middle life") which he invented.BOOK, Rudwick, Martin, Worlds Before Adam: The Reconstruction of Geohistory in the Age of Reform, 2008, 539–545,

Dating of time scales

When William Smith and Sir Charles Lyell first recognized that rock strata represented successive time periods, time scales could be estimated only very imprecisely since estimates of rates of change were uncertain. While creationists had been proposing dates of around six or seven thousand years for the age of Earth based on the Bible, early geologists were suggesting millions of years for geologic periods, and some were even suggesting a virtually infinite age for Earth.{{citation needed|date=September 2017}} Geologists and paleontologists constructed the geologic table based on the relative positions of different strata and fossils, and estimated the time scales based on studying rates of various kinds of weathering, erosion, sedimentation, and lithification. Until the discovery of radioactivity in 1896 and the development of its geological applications through radiometric dating during the first half of the 20th century, the ages of various rock strata and the age of Earth were the subject of considerable debate.The first geologic time scale that included absolute dates was published in 1913 by the British geologist Arthur Holmes.WEB,weblink Geologic Time Scale,, He greatly furthered the newly created discipline of geochronology and published the world-renowned book The Age of the Earth in which he estimated Earth's age to be at least 1.6 billion years.WEB,weblink How the discovery of geologic time changed our view of the world, Bristol University, In 1977, the Global Commission on Stratigraphy (now the International Commission on Stratigraphy) began to define global references known as GSSP (Global Boundary Stratotype Sections and Points) for geologic periods and faunal stages. The commission's work is described in the 2012 geologic time scale of Gradstein et al.BOOK, Felix, Gradstein, James, Ogg, Mark, Schmitz, Gabi, Ogg, The Geologic Time Scale 2012, Elsevier B.V., 2012, 978-0-444-59425-9, A UML model for how the timescale is structured, relating it to the GSSP, is also available.JOURNAL, Cox, Simon J. D., Richard, Stephen M., 2005, A formal model for the geologic time scale and global stratotype section and point, compatible with geospatial information transfer standards, Geosphere, 1, 3, 119–137, 10.1130/GES00022.1,weblink 31 December 2012, 2005Geosp...1..119C,

The Anthropocene

Popular culture and a growing number{{citation needed|date=June 2018}} of scientists use the term "Anthropocene" informally to label the current epoch in which we are living. The term was coined by Paul Crutzen and Eugene Stoermer in 2000 to describe the current time in which humans have had an enormous impact on the environment. It has evolved to describe an "epoch" starting some time in the past and on the whole defined by anthropogenic carbon emissions and production and consumption of plastic goods that are left in the ground.WEB, Anthropocene: Age of Man – Pictures, More From National Geographic Magazine,weblink, 2015-09-22, Critics of this term say that the term should not be used because it is difficult, if not nearly impossible, to define a specific time when humans started influencing the rock strata—defining the start of an epoch.WEB, What is the Anthropocene and Are We in It?,weblink 2015-09-22, Joseph, Stromberg, Others say that humans have not even started to leave their biggest impact on Earth, and therefore the Anthropocene has not even started yet.The ICS has not officially approved the term {{As of|2015|9|lc=y}}.WEB, Subcommission on Quaternary Stratigraphy, Working Group on the 'Anthropocene',weblink International Commission on Stratigraphy, The Anthropocene Working Group met in Oslo in April 2016 to consolidate evidence supporting the argument for the Anthropocene as a true geologic epoch. Evidence was evaluated and the group voted to recommend "Anthropocene" as the new geological age in August 2016weblink the International Commission on Stratigraphy approve the recommendation, the proposal to adopt the term will have to be ratified by the International Union of Geological Sciences before its formal adoption as part of the geologic time scale.WEB, George Dvorsky,weblink New Evidence Suggests Human Beings Are a Geological Force of Nature
date=, 2016-10-15,

Table of geologic time

The following table summarizes the major events and characteristics of the periods of time making up the geologic time scale. This table is arranged with the most recent geologic periods at the top, and the most ancient at the bottom. The height of each table entry does not correspond to the duration of each subdivision of time.The content of the table is based on the current official geologic time scale of the International Commission on Stratigraphy,WEB,weblink International Stratigraphic Chart, International Commission on Stratigraphy, yes,weblink" title="">weblink 30 May 2014, with the epoch names altered to the early/late format from lower/upper as recommended by the ICS when dealing with chronostratigraphy.A service providing a Resource Description Framework/Web Ontology Language representation of the timescale is available through the Commission for the Management and Application of Geoscience Information GeoSciML project as a serviceWEB,weblink 2014-08-03, Geologic Timescale Elements in the International Chronostratigraphic Chart, and at a SPARQL end-point.WEB,weblinkweblink" title="">weblink yes, 2014-08-06, 2014-08-03, SPARQL endpoint for CGI timescale service, Simon J. D., Cox, JOURNAL, A geologic timescale ontology and service, Simon J. D., Cox, Stephen M., Richard, 10.1007/s12145-014-0170-6, 8, Earth Science Informatics, 5–19, 2014, {| class="wikitable collapsible" style="clear:both;margin:0; font-size:95%"
n/a{{efn|References to the "Post-Cambrian Supereon" are not universally accepted, and therefore must be considered unofficial.}}PhanerozoicCenozoic{{efn>Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. The 2009 version of the ICS time chartHTTP://WWW.STRATIGRAPHY.ORG/UPLOAD/ISCHART2009.PDF >TITLE=ARCHIVED COPY DEADURL=YES ARCHIVEDATE=29 DECEMBER 2009, dmy-all, recognizes a slightly extended Quaternary as well as the Paleogene and a truncated Neogene, the Tertiary having been demoted to informal status.}}QuaternaryHoloceneMeghalayan4.2 kiloyear event, Little Ice Age, increasing Industrial Revolution>industrial CO2.meghalayan}}*
Northgrippian|8.2 kiloyear event, Holocene climatic optimum. Bronze Age.northgrippian}}*
Greenlandianinterglacial begins. Sea level flooding of Doggerland and Sundaland. Sahara desert forms. Neolithic Revolution>Neolithic agriculture.greenlandian}}*
PleistoceneLate Pleistocene>Late ('Tarantian')Eemian interglacial, Last glacial period, ending with Younger Dryas. Toba catastrophe theory>Toba eruption. Megafauna extinction.Late pleistocene}}
Middle Pleistocene>Middle ('Ionian', 'Chibanian')100,000-year problem>100 ka glacial cycles. Rise of Homo sapiens.middle pleistocene}}
Early Pleistocene>Calabrian|Further cooling of the climate. Spread of Homo erectus.calabrian}}*
Gelasian|Start of Quaternary glaciations. Rise of the Pleistocene megafauna and Homo habilis.gelasian}}*
ZancleanZanclean flooding of the Mediterranean Basin. Cooling climate. Ardipithecus in Africa.NOVA, ALIENS FROM EARTH: WHO'S WHO IN HUMAN EVOLUTION FIRST=PETER PUBLISHER=PBS URL=HTTPS://WWW.PBS.ORG/WGBH/NOVA/HOBBIT/TREE-NF.HTML, zanclean}}*
MioceneMessinianMessinian Event with hypersaline lakes in empty Mediterranean Basin. Greenhouse and Icehouse Earth, punctuated by ice ages and re-establishment of East Antarctic Ice Sheet; Gradual separation of Chimpanzee–human last common ancestor>human and chimpanzee ancestors. Sahelanthropus tchadensis in Africa.messinian}}*
SerravallianWarmer during Middle Miocene Climate Optimum.weblink Extinctions in Middle Miocene disruption.serravallian}}*
BurdigalianOrogeny in Northern Hemisphere. Start of Kaikoura Orogeny forming Southern Alps in New Zealand. Widespread forests slowly photosynthesis massive amounts of CO2, gradually lowering the level of atmospheric CO2 from 650 ppmv down to around 100 ppmv during the Miocene.ROYER journal=Geochimica et Cosmochimica Acta pages=5665–75 url= first1=Dana L. bibcode = 2006GeCoA..70.5665R }}{{efnFor more information on this, see Atmosphere of Earth#Evolution of Earth's atmosphere, Carbon dioxide in the Earth's atmosphere, and Climate change. Specific graphs of reconstructed CO2 levels over the past ~550, 65, and 5 million years can be seen at (:File:Phanerozoic Carbon Dioxide.png), (:File:65 Myr Climate Change.png), (:File:Five Myr Climate Change.png), respectively.}} Modern mammal and bird families become recognizable. Equidae and mastodons diverse. Grasses become ubiquitous. Ancestor of apes, including humans.HTTPS://WWW.LIVESCIENCE.COM/60093-LAST-COMMON-ANCESTOR-OF-APES-HUMANS-REVEALED.HTML, Here's What the Last Common Ancestor of Apes and Humans Looked Like, burdigalian}}
Aquitanian age>Aquitanianaquitanian}}*
PaleogeneOligoceneChattian Eocene–Oligocene extinction event extinction. Start of widespread Late Cenozoic Ice Age>Antarctic glaciation.10.1038/NATURE01290>PMID = 12529638 JOURNAL=NATURE ISSUE=6920 YEAR=2003 FIRST1=ROBERT M. FIRST2=DAVID, 2003Natur.421..245D, Rapid evolution and diversification of fauna, especially mammals. Major evolution and dispersal of modern types of flowering plantschattian}}
EocenePriabonian Greenhouse and Icehouse Earth. Archaic mammals (e.g. Creodonts, "Condylarths", Uintatheriidae>Uintatheres, etc.) flourish and continue to develop during the epoch. Appearance of several "modern" mammal families. Primitive Cetacea diversify. Reglaciation of Antarctica and formation of its ice cap; End of Laramide Orogeny>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. priabonian}}
YpresianPaleocene–Eocene Thermal Maximum>PETM and Eocene Thermal Maximum 2) and warming climate until the Eocene Climatic Optimum. The Azolla event decreased CO2 levels from 3500 ppm to 650 ppm, setting the stage for a long period of cooling.{{efn> name="atmospheric-carbon-dioxide"}} Indian Subcontinent collides with Asia and starts Himalayan Orogeny.ypresian}}*
PaleoceneThanetian Starts with Chicxulub impact and the K-Pg extinction event. Greenhouse and Icehouse Earth. Modern plants appear; Mammals diversify into a number of lineages following the extinction of the non-avian dinosaurs. First large mammals (up to bear or small hippopotamus>hippo size). Alpine orogeny in Europe and Asia begins. thanetian}}*
MesozoicCretaceousLate Cretaceous>LateMaastrichtian Flowering plants proliferate, along with new types of insects. More modern teleost fish begin to appear. Ammonoidea, Belemnoidea, rudist Bivalvia>bivalves, Echinoideas and Porifera>sponges all common. Many new types of dinosaurs (e.g. Tyrannosauridae, Titanosauridae>Titanosaurs, Hadrosauridae, and Ceratopsidae>Ceratopsids) evolve on land, as do Eusuchia (Crocodilia); and mosasaurs and modern sharks appear in the sea. Birds toothed and toothless coexist with pterosaurs. Monotremes, marsupials and Eutheria>placental mammals appear. Break up of Gondwana. Beginning of Laramide Orogeny and Sevier Orogeny>Sevier Orogenies of the Rocky Mountains. atmospheric CO2 close to present-day levels.maastrichtian}} ± 0.2*
Campaniancampanian}} ± 0.2
Santoniansantonian}} ± 0.5*
Coniacianconiacian}} ± 0.3
Early Cretaceous>EarlyAlbianalbian}}
JurassicLate Jurassic>LateTithonian 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 Squamata. Ichthyosaurs and plesiosaurs diverse. Bivalvia>Bivalves, Ammonites and Belemnoidea abundant. Sea urchins very common, along with crinoids, starfish, Porifera>sponges, and Terebratulida and Rhynchonellida>rhynchonellid brachiopods. Breakup of Pangaea into Gondwana and Laurasia. Nevadan orogeny in North America. Rangitata Orogeny and Cimmerian Orogeny>Cimmerian orogenies taper off. Atmospheric CO2 levels 3–4 times the present day levels (1200–1500 ppmv, compared to today's 400 ppmv{{efn|name="atmospheric-carbon-dioxide"}}).tithonian}} ± 0.9
Kimmeridgiankimmeridgian}} ± 1.0
Oxfordian stage>Oxfordianoxfordian}} ± 1.0
Middle Jurassic>MiddleCalloviancallovian}} ± 1.2
Bathonianbathonian}} ± 1.3*
Bajocianbajocian}} ± 1.4*
Aalenianaalenian}} ± 1.0*
Early Jurassic>EarlyToarciantoarcian}} ± 0.7*
Pliensbachianpliensbachian}} ± 1.0*
Sinemuriansinemurian}} ± 0.3*
Hettangianhettangian}} ± 0.2*
TriassicLate Triassic>LateRhaetian Archosaurs dominant on land as dinosaurs and in the air as pterosaurs. Ichthyosaurs and nothosaurs dominate large marine fauna. Cynodonts become smaller and more mammal-like, while first mammals and crocodilia appear. Dicroidiumflora common on land. Many large aquatic temnospondyli amphibians. Ammonite>Ceratitic ammonoids extremely common. Scleractinia and teleost fish appear, as do many modern insect clades. Andes Mountains>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)rhaetian}}
Middle Triassic>MiddleLadinianladinian}}*
Early Triassic>EarlyOlenekianolenekian}}
Induaninduan}} ± 0.06*
PaleozoicPermianLopingianChanghsingian Landmasses unite into supercontinent Pangaea, creating the Appalachian Mountainss. End of Permo-Carboniferous glaciation. Synapsida>Synapsids including (pelycosaurs and therapsids) become plentiful, while parareptiles and temnospondyli amphibians remain common. In the mid-Permian, coal-age flora are replaced by Conifer cone>cone-bearing gymnosperms (the first true seed plants) and by the first true mosses. Beetles and Fly evolve. Marine life flourishes in warm shallow reefs; Productida>productid and Spiriferida brachiopods, bivalves, foraminifera>forams, and orthocerids all abundant. Permian-Triassic extinction event occurs 251 Year#SI prefix multipliers>Ma: 95% of life on Earth becomes extinct, including all trilobites, graptolites, and blastoids. Ouachita Orogeny and Innuitian orogeny>Innuitian orogenies in North America. Uralian orogeny in Europe/Asia tapers off. Altai Mountains orogeny in Asia. Hunter-Bowen Orogeny on Australia (continent)>Australian continent begins (c. 260–225 Ma), forming the MacDonnell Ranges.changhsingian}} ± 0.07*
Wuchiapingianwuchiapingian}} ± 0.4*
GuadalupianCapitaniancapitanian}} ± 0.4*
Wordianwordian}} ± 0.5*
Roadianroadian}} ± 0.5*
CisuralianKunguriankungurian}} ± 0.6
Artinskianartinskian}} ± 0.26
Sakmariansakmarian}} ± 0.18
Asselianasselian}} ± 0.15*
Carboniferous>Carbon-iferous{{efnMississippian age>Mississippian and Pennsylvanian Periods.}}Pennsylvanian (geology)>PennsylvanianGzhelian Pterygota radiate suddenly; some (esp. Protodonata and Palaeodictyoptera) are quite large. Amphibians common and diverse. First reptiles and coal forests (Lepidodendron>scale trees, ferns, Sigillarias, Calamites>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.gzhelian}} ± 0.1
Kasimoviankasimovian}} ± 0.1
Moscovian (Carboniferous)>Moscovianmoscovian}} ± 0.2
Bashkirianbashkirian}} ± 0.4*
Mississippian age>MississippianSerpukhovian Large Lycopodiophytas, first Tetrapoda>land vertebrates, and amphibious eurypterids live amid coal-forming coastal brackish water>swamps. Lobe-finned rhizodonts are dominant big fresh-water predators. In the oceans, early Chondrichthyess are common and quite diverse; echinoderms (especially crinoids and blastoids) abundant. Corals, bryozoa, Goniatitida>goniatites and brachiopods (Productida, Spiriferida, etc.) very common, but Trilobitas and nautiloids decline. Glaciation in East Gondwana. Mayor Island/Tuhua>Tuhua Orogeny in New Zealand tapers off.serpukhovian}} ± 0.2
Viséanvisean}} ± 0.4*
Tournaisiantournaisian}} ± 0.4*
DevonianLate Devonian>LateFamennian First Lycopodiopsidaes, Equisetophyta>horsetails and ferns appear, as do the first seed-bearing plants (progymnosperms), first trees (the progymnosperm Archaeopteris), and first (wingless) insects. Strophomenida and Atrypida>atrypid brachiopods, Rugosa and Tabulata>tabulate corals, and crinoids are all abundant in the oceans. Goniatite Ammonite are plentiful, while squid-like Coleoidea>coleoids arise. Trilobites and armoured agnaths decline, while jawed fishes (Placodermis, Sarcopterygii>lobe-finned and Osteichthyes fish, and early Chondrichthyes>sharks) rule the seas. First tetrapods still aquatic. "Old Red Continent" of Euramerica. Beginning of Acadian Orogeny for Atlas Mountains of North Africa, and Appalachian Mountains of North America, also the Antler Orogeny>Antler, Variscan Orogeny, and Mayor Island/Tuhua>Tuhua Orogeny in New Zealand.famennian}} ± 1.6*
Frasnianfrasnian}} ± 1.6*
Middle Devonian>MiddleGivetiangivetian}} ± 0.8*
Eifelianeifelian}} ± 1.2*
Early Devonian>EarlyEmsianemsian}} ± 2.6*
Pragianpragian}} ± 2.8*
Lochkovianlochkovian}} ± 3.2*
SilurianPridoli epoch>Pridoli First vascular plants (the rhyniophytes and their relatives), first millipedes and Arthropleuridas on land. First jawed fishes, as well as many ostracoderm>armoured agnatha, populate the seas. Eurypterid>Sea-scorpions reach large size. Tabulate coral and Rugosa>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.pridoli}} ± 2.3*
Ludlow epoch>LudlowLudfordianludfordian}} ± 0.9*
Gorstiangorstian}} ± 0.5*
Wenlock epoch>WenlockHomerianhomerian}} ± 0.7*
Sheinwoodiansheinwoodian}} ± 0.8*
Llandovery epoch>LlandoveryTelychiantelychian}} ± 1.1*
Aeronianaeronian}} ± 1.2*
Rhuddanianrhuddanian}} ± 1.5*
OrdovicianLate Ordovician>LateHirnantian Invertebrates diversify into many new types (e.g., long orthoconic orthocerida>cephalopods). Early corals, articulate brachiopods (Orthida, Strophomenida, etc.), Bivalvia, nautiloids, trilobites, ostracods, bryozoa, many types of echinoderms (crinoids, Cystoidea>cystoids, Asteroidea, etc.), branched graptolites, and other taxa all common. Conodonts (early planktonic vertebrates) appear. First Embryophyte>green plants and fungi on land. Ice age at end of period.hirnantian}} Â± 1.4*
Katiankatian}} Â± 0.7*
Sandbiansandbian}} Â± 0.9*
Middle Ordovician>MiddleDarriwiliandarriwilian}} Â± 1.1*
Dapingiandapingian}} Â± 1.4*
Early Ordovician>EarlyFloian(formerly Arenig)floian}} Â± 1.4*
Tremadociantremadocian}} Â± 1.9*
CambrianFurongianCambrian Stage 10>Stage 10 Major diversification of life in the Cambrian Explosion. Numerous fossils; most modern Animalia Phylum>phyla appear. First chordates appear, along with a number of extinct, problematic phyla. Reef-building Archaeocyatha abundant; then vanish. Trilobites, priapulid worms, Porifera, inarticulate brachiopods (unhinged lampshells), and numerous other animals. Anomalocarids are giant predators, while many Ediacaran fauna die out. Prokaryotes, protists (e.g., forams), fungus>fungi and algae continue to present day. Gondwana emerges. Petermann Orogeny on the Australia (continent) tapers off (550–535 Year#SI prefix multipliers>Ma). Ross Orogeny in Antarctica. Adelaide Geosyncline, majority of orogenic activity from 514–500 Year#SI prefix multipliers>Ma. Lachlan Orogeny on Australia (continent), c. 540–440 Year#SI prefix multipliers>Ma. Atmosphere of Earth CO2 content roughly 15 times present-day (Holocene) levels (6000 ppmv compared to today's 400 ppmv){{efn>name="atmospheric-carbon-dioxide"}}
Wuliuancambrian stage 5}}
Cambrian Series 2>Series 2Cambrian Stage 4>Stage 4cambrian stage 4}}
Cambrian Stage 3>Stage 3cambrian stage 3}}
TerreneuvianCambrian Stage 2>Stage 2cambrian stage 2}}
Fortunianfortunian}} Â± 1.0*
Precambrian{{efn>name="aka-cryptozoic"|The Precambrian is also known as Cryptozoic.}}Proterozoic{{efn>name="Precambrian-Time"Proterozoic, Archean and Hadean are often collectively referred to as the Precambrian>Precambrian Time or sometimes, also the Cryptozoic.}}Neoproterozoic{{efn>name="Precambrian-Time"}}Ediacaran Good fossils of the first Metazoas. Ediacaran biota flourish worldwide in seas. Simple trace fossils of possible worm-like Trichophycus pedum>Trichophycus, etc. First Poriferas and Trilobita>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 Australia (continent). Beardmore Orogeny in Antarctica, 633–620 Year#SI prefix multipliers>Ma.ediacaran}}*
Cryogenian Possible "Snowball Earth" period. Fossils still rare. Rodinia landmass begins to break up. Late Ruker / Nimrod Orogeny in Antarctica tapers off.cryogenian}}{{efnDefined by absolute age (Global Standard Stratigraphic Age).}}
Tonian Rodinia supercontinent persists. Sveconorwegian orogeny ends. Trace fossils of simple multicellular Eukaryota>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, 1,000 Â± 150 Year#SI prefix multipliers. Edmundian Orogeny (c. 920 – 850 Year#SI prefix multipliers>Ma), Gascoyne Complex, Western Australia. Adelaide Geosyncline laid down on Australia (continent), beginning of Adelaide Geosyncline>Adelaide Geosyncline (Delamerian Orogeny) in Australia.tonian}}{{efn|name="absolute-age"}}
Mesoproterozoic{{efn>name="Precambrian-Time"}}Stenian Narrow highly Metamorphic rock belts due to orogeny as Rodinia forms. Sveconorwegian orogeny starts. Late Ruker / Nimrod Orogeny in Antarctica possibly begins. Musgrave Orogeny (c. 1,080 Year#SI prefix multipliers>Ma), Musgrave Block, Central Australia. stenian}}{{efn|name="absolute-age"}}
Ectasian Platform covers continue to expand. Green algae colonies in the seas. Grenville Orogeny in North America.ectasian}}{{efn|name="absolute-age"}}
Calymmian Platform covers expand. Barramundi Orogeny, McArthur Basin, Northern Australia, and Isan Orogeny, circa1,600 Year#SI prefix multipliers>Ma, Mount Isa Block, Queenslandcalymmian}}{{efn|name="absolute-age"}}
Paleoproterozoic{{efn> name="Precambrian-Time"}}Statherian First Eukaryote: protists with nuclei. Columbia (supercontinent)>Columbia is the primordial supercontinent. Kimban Orogeny in Australian continent ends. Yapungku Orogeny on Yilgarn craton, in Western Australia. Mangaroon Orogeny, 1,680–1,620 Year#SI prefix multipliers, on the Gascoyne Complex in Western Australia. Kararan Orogeny (1,650 Year#SI prefix multipliers>Ma), Gawler Craton, South Australia.statherian}}{{efn|name="absolute-age"}}
Orosirian The Atmosphere of Earth becomes oxygenic. Vredefort crater>Vredefort and Sudbury Basin asteroid impacts. Much orogeny. Penokean orogeny and Trans-Hudsonian Orogeny>Trans-Hudsonian Orogenies in North America. Early Ruker Orogeny in Antarctica, 2,000–1,700 Year#SI prefix multipliers. Glenburgh Orogeny, Gascoyne Complex>Glenburgh Terrane, Australia (continent) circa>c. 2,005–1,920 Ma. Kimban Orogeny, Gawler craton in Australian continent begins.orosirian}}{{efn|name="absolute-age"}}
Rhyacian Bushveld Igneous Complex forms. Huronian glaciation.rhyacian}}{{efn|name="absolute-age"}}
Siderian Oxygen catastrophe: banded iron formations forms. Sleaford Orogeny on Australia (continent), Gawler Craton 2,440–2,420 Year#SI prefix multipliers>Ma.siderian}}{{efn|name="absolute-age"}}
Archean{{efn>name="Precambrian-Time"}}Neoarchean{{efn>name="Precambrian-Time"}} Stabilization of most modern cratons; possible Mantle (geology) overturn event. Insell Orogeny, 2,650 Â± 150 Year#SI prefix multipliers>Ma. Abitibi greenstone belt in present-day Ontario and Quebec begins to form, stabilizes by 2,600 Ma.neoarchean}}{{efn|name="absolute-age"}}
Mesoarchean{{efn>name="Precambrian-Time"}} First stromatolites (probably colony (biology) cyanobacteria). Oldest macrofossils. Humboldt Orogeny in Antarctica. Blake River Megacaldera Complex begins to form in present-day Ontario and Quebec, ends by roughly 2,696 Year#SI prefix multipliers>Ma.mesoarchean}}{{efn|name="absolute-age"}}
Paleoarchean{{efn>name="Precambrian-Time"}} First known phototroph bacteria. Oldest definitive microfossils. Oldest cratons on Earth (such as the Canadian Shield and the Pilbara Craton) may have formed during this period.{{efn>name="Oldest-craton"|The age of the oldest measurable craton, or continental crust, is dated to 3,600–3,800 Ma.}} Rayner Orogeny in Antarctica.paleoarchean}}{{efn|name="absolute-age"}}
Eoarchean{{efn>name="Precambrian-Time"}} Prokaryote (probably bacteria and archaea). Oldest probable microfossils. The first organism>life forms and self-replication RNA molecules evolve around 4,000 Year#SI prefix multipliers>Ma, after the Late Heavy Bombardment ends on Earth. Napier Mountains Orogeny in Antarctica, 4,000 Â± 200 Year#SI prefix multipliers>Ma.eoarchean}}
Hadean{{efn>name="Precambrian-Time"}}{{efnThough commonly used, the Hadean is not a formal eonA CONCISE GEOLOGIC TIME SCALE: 2016 > PUBLISHER=ELSEVIER LAST=OGG LAST2=OGG LAST3=GRADSTEIN PAGES=20 lunar geologic timescale. These eras include the Cryptic era>Cryptic and Basin Groups (which are subdivisions of the Pre-Nectarian era), Nectarian, and Early Imbrian units.}}Early Imbrian (Neohadean) (unofficial){{efn>name="Precambrian-Time"}}{{efnThese unit names were taken from the lunar geologic timescale and refer to geologic events that did not occur on Earth. Their use for Earth geology is unofficial. Note that their start times do not dovetail perfectly with the later, terrestrially defined boundaries.}} Indirect photosynthetic evidence (e.g., kerogen) of primordial life. This era overlaps the beginning of the Late Heavy Bombardment of the Inner Solar System Solar System, produced possibly by the planetary migration of Neptune into the Kuiper belt as a result of orbital resonances between Jupiter and Saturn. Oldest known rock (4,031 to 3,580 Year#SI prefix multipliers>Ma).10.1007/S004100050465>TITLE=PRISCOAN (4.00–4.03 GA) ORTHOGNEISSES FROM NORTHWESTERN CANADALAST=BOWRINGJOURNAL=CONTRIBUTIONS TO MINERALOGY AND PETROLOGYISSUE=1LAST2=WILLIAMSBIBCODE=1999COMP..134....3B, The oldest rock on Earth is the Acasta Gneiss, and it dates to 4.03 Ga, located in the Northwest Territories of Canada.
Nectarian (Mesohadean) (unofficial){{efn>name="Precambrian-Time"}}{{efn|name="Lunar-geologic-timescale-names"}} Possible first appearance of plate tectonics. This unit gets its name from the lunar geologic timescale when the Nectaris Basin and other greater lunar basins form by big impact events. Earliest evidence for life based on unusually high amounts of light isotopes of carbon, a common sign of life.
Basin Groups (Paleohadean) (unofficial){{efn>name="Precambrian-Time"}}{{efn| name="Lunar-geologic-timescale-names"}}End of the Early Bombardment Phase. Oldest known mineral (Zircon, 4,404 Â± 8 Year#SI prefix multipliers). Asteroids and comets bring water to Earth.HTTP://WWW.GEOLOGY.WISC.EDU/%7EVALLEY/ZIRCONS/WILDE2001NATURE.PDF,,
Cryptic era>Cryptic (Cryptic era) (unofficial){{efn>name="Precambrian-Time"}}{{efn|name="Lunar-geologic-timescale-names"}} Formation of Moon (4,533 to 4,527 Year#SI prefix multipliers), probably from Giant impact hypothesis>giant impact, since the end of this era. Formation of Earth (4,570 to 4,567.17 Year#SI prefix multipliers), Early Bombardment Phase begins. Formation of Sun (4,680 to 4,630 Year#SI prefix multipliers>Ma) .hadean}}

Proposed Precambrian timeline

The ICS's Geologic Time Scale 2012 book which includes the new approved time scale also displays a proposal to substantially revise the Precambrian time scale to reflect important events such as the formation of the Earth or the Great Oxidation Event, among others, while at the same time maintaining most of the previous chronostratigraphic nomenclature for the pertinent time span.BOOK, Van Kranendonk, Martin J., The geologic time scale 2012, 2012, Elsevier, Amsterdam, 978-0-44-459425-9, 359–365, 1st, Felix M. Gradstein, James G. Ogg, Mark D. Schmitz, abi M. Ogg, 16: A Chronostratigraphic Division of the Precambrian: Possibilities and Challenges,weblink (See also Period (geology)#Structure.)
  • Hadean Eon – 4600–4031 MYA{{Contradict inline|Chaotian|date=November 2016}}
    • Chaotian Era – 4600–4404 MYA – the name alluding both to the mythological Chaos and the chaotic phase of planet formationJOURNAL, Goldblatt, C., K. J., Zahnle, N. H., Sleep, E. G., Nisbet, The Eons of Chaos and Hades, Solid Earth, 2010, 1, 1–3,weblink 2010SolE....1....1G, 10.5194/se-1-1-2010, JOURNAL, Chambers, John E., Planetary accretion in the inner Solar System, Earth and Planetary Science Letters, July 2004, 223, 3–4, 241–252, 10.1016/j.epsl.2004.04.031,weblink 2004E&PSL.223..241C, {{Contradict inline|Chaotian|date=November 2016}}
    • Jack Hillsian or Zirconian Era – 4404–4031 MYA – both names allude to the Jack Hills Greenstone Belt which provided the oldest mineral grains on Earth, zircons
  • Archean Eon – 4031–2420 MYA
  • Proterozoic Eon – 2420–541 MYA
    • Paleoproterozoic Era – 2420–1780 MYA
      • Oxygenian Period – 2420–2250 MYA – named for displaying the first evidence for a global oxidizing atmosphere
      • Jatulian or Eukaryian Period – 2250–2060 MYA – names are respectively for the Lomagundi–Jatuli δ13C isotopic excursion event spanning its duration, and for the (proposed)JOURNAL, El Albani, Abderrazak, Bengtson, Stefan, Canfield, Donald E., Riboulleau, Armelle, Rollion Bard, Claire, Macchiarelli, Roberto, etal, The 2.1 Ga Old Francevillian Biota: Biogenicity, Taphonomy and Biodiversity, PLoS ONE, 2014, 9, 6, e99438, 10.1371/journal.pone.0099438, 2014PLoSO...999438E, 24963687, 4070892, JOURNAL, El Albani, Abderrazak, Bengtson, Stefan, Canfield, Donald E., Bekker, Andrey, Macchiarelli, Roberto, Mazurier, Arnaud, Hammarlund, Emma U., etal, Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago, Nature, 2010, 466, 7302, 100–104, 10.1038/nature09166, 20596019,weblink 2010Natur.466..100A, first fossil appearance of eukaryotes
      • Columbian Period – 2060–1780 MYA – named after the supercontinent Columbia
    • Mesoproterozoic Era – 1780–850 MYA
      • Rodinian Period – 1780–850 MYA – named after the supercontinent Rodinia, stable environment
    • Neoproterozoic Era – 850–541 MYA
      • Cryogenian Period – 850–630 MYA – named for the occurrence of several glaciations
      • Ediacaran Period – 630–541 MYA
Shown to scale:ImageSize = width:800 height:120PlotArea = left:65 right:15 bottom:20 top:5AlignBars = justifyColors =
id:precambrian value:rgb(0.968,0.262,0.439)
id:proterozoic value:rgb(0.968,0.207,0.388)
id:neoproterozoic value:rgb(0.996,0.701,0.258)
id:ediacaran value:rgb(0.996,0.85,0.415)
id:cryogenian value:rgb(0.996,0.8,0.36)
id:tonian value:rgb(0.996,0.75,0.305)
id:mesoproterozoic value:rgb(0.996,0.705,0.384)
id:rodinian value:rgb(0.996,0.75,0.478)
id:paleoproterozoic value:rgb(0.968,0.263,0.44)
id:columbian value:rgb(0.968,0.459,0.655)
id:eukaryian value:rgb(0.968,0.408,0.596)
id:oxygenian value:rgb(0.968,0.357,0.537)
id:archean value:rgb(0.996,0.157,0.498)
id:neoarchean value:rgb(0.976,0.608,0.757)
id:siderian value:rgb(0.976,0.7,0.85)
id:methanian value:rgb(0.976,0.65,0.8)
id:mesoarchean value:rgb(0.968,0.408,0.662)
id:pongolan value:rgb(0.968,0.5,0.75)
id:vaalbaran value:rgb(0.968,0.45,0.7)
id:paleoarchean value:rgb(0.96,0.266,0.624)
id:isuan value:rgb(0.96,0.35,0.65)
id:acastan value:rgb(0.96,0.3,0.6)
id:hadean value:rgb(0.717,0,0.494)
id:zirconian value:rgb(0.902,0.114,0.549)
id:chaotian value:rgb(0.8,0.05,0.5)
id:black value:black
id:white value:white
Period = from:-4600 till:-541TimeAxis = orientation:horizontalScaleMajor = unit:year increment:500 start:-4500ScaleMinor = unit:year increment:100 start:-4500Define $markred = text:"*" textcolor:red shift:(0,3) fontsize:10PlotData=
align:center textcolor:black fontsize:8 mark:(line,black) width:25 shift:(0,-5)


from: start till: -541 text:Precambrian color:precambrian


from: -2420 till: -541 text:Proterozoic color:proterozoic
from: -4031 till: -2420 text:Archean color:archean
from: start till: -4031 text:Hadean color:hadean


from: -850 till: -541 text:Neoproterozoic color:neoproterozoic
from: -1780 till: -850 text:Mesoproterozoic color:mesoproterozoic
from: -2420 till: -1780 text:Paleoproterozoic color:paleoproterozoic
from: -2780 till: -2420 text:Neoarchean color:neoarchean
from: -3490 till: -2780 text:Mesoarchean color:mesoarchean
from: -4031 till: -3490 text:Paleoarchean color:paleoarchean
from: -4404 till: -4031 text:Zirconian color:zirconian
from: start till: -4404 text:Chaotian color:chaotian



from: -630 till: -541 text:Ed. color:ediacaran
from: -850 till: -630 text:Cryogenian color:cryogenian
from: -1780 till: -850 text:Rodinian color:rodinian
from: -2060 till: -1780 text:Columbian color:columbian
from: -2250 till: -2060 text:Eukaryian color:eukaryian
from: -2420 till: -2250 text:Oxygenian color:oxygenian
from: -2630 till: -2420 text:Siderian color:siderian
from: -2780 till: -2630 text:Methanian color:methanian
from: -3020 till: -2780 text:Pongolan color:pongolan
from: -3490 till: -3020 text:Vaalbaran color:vaalbaran
from: -3810 till: -3490 text:Isuan color:isuan
from: -4031 till: -3810 text:Acastan color:acastan
from: start till: -4031 color:white
Compare with the current official timeline, not shown to scale:ImageSize = width:1100 height:120PlotArea = left:65 right:15 bottom:20 top:5AlignBars = justifyColors =
id:precambrian value:rgb(0.968,0.262,0.439)
id:proterozoic value:rgb(0.968,0.207,0.388)
id:neoproterozoic value:rgb(0.996,0.701,0.258)
id:ediacaran value:rgb(0.996,0.85,0.415)
id:cryogenian value:rgb(0.996,0.8,0.36)
id:tonian value:rgb(0.996,0.75,0.305)
id:mesoproterozoic value:rgb(0.996,0.705,0.384)
id:stenian value:rgb(0.996,0.85,0.604)
id:ectasian value:rgb(0.996,0.8,0.541)
id:calymmian value:rgb(0.996,0.75,0.478)
id:paleoproterozoic value:rgb(0.968,0.263,0.44)
id:statherian value:rgb(0.968,0.459,0.655)
id:orosirian value:rgb(0.968,0.408,0.596)
id:rhyacian value:rgb(0.968,0.357,0.537)
id:siderian value:rgb(0.968,0.306,0.478)
id:archean value:rgb(0.996,0.157,0.498)
id:neoarchean value:rgb(0.976,0.608,0.757)
id:mesoarchean value:rgb(0.968,0.408,0.662)
id:paleoarchean value:rgb(0.96,0.266,0.624)
id:eoarchean value:rgb(0.902,0.114,0.549)
id:hadean value:rgb(0.717,0,0.494)
id:black value:black
id:white value:white
Period = from:-4600 till:-541TimeAxis = orientation:horizontalScaleMajor = unit:year increment:500 start:-4500ScaleMinor = unit:year increment:100 start:-4500Define $markred = text:"*" textcolor:red shift:(0,3) fontsize:10PlotData=
align:center textcolor:black fontsize:8 mark:(line,black) width:25 shift:(0,-5)


from: start till: -541 text:Precambrian color:precambrian


from: -2500 till: -541 text:Proterozoic color:proterozoic
from: -4031 till: -2500 text:Archean color:archean
from: start till: -4031 text:Hadean color:hadean


from: -1000 till: -541 text:Neoproterozoic color:neoproterozoic
from: -1600 till: -1000 text:Mesoproterozoic color:mesoproterozoic
from: -2500 till: -1600 text:Paleoproterozoic color:paleoproterozoic
from: -2800 till: -2500 text:Neoarchean color:neoarchean
from: -3200 till: -2800 text:Mesoarchean color:mesoarchean
from: -3600 till: -3200 text:Paleoarchean color:paleoarchean
from: -4031 till: -3600 text:Eoarchean color:eoarchean
from: start till: -4031 color:white


from: -635 till: -541 text:Ed. color:ediacaran
from: -720 till: -635 text:Cr. color:cryogenian
from: -1000 till: -720 text:Tonian color:tonian
from: -1200 till: -1000 text:Stenian color:stenian
from: -1400 till: -1200 text:Ectasian color:ectasian
from: -1600 till: -1400 text:Calymmian color:calymmian
from: -1800 till: -1600 text:Statherian color:statherian
from: -2050 till: -1800 text:Orosirian color:orosirian
from: -2300 till: -2050 text:Rhyacian color:rhyacian
from: -2500 till: -2300 text:Siderian color:siderian
from: start till: -2500 color:white

See also

{{div col|colwidth=22em}} {{div col end}}





Further reading

  • JOURNAL, 2009, Aubry, Marie-Pierre, Van Couvering, John A., Christie-Blick, Nicholas, Landing, Ed, Pratt, Brian R., Owen, Donald E., Ferrusquia-Villafranca, Ismael, Terminology of geological time: Establishment of a community standard, Stratigraphy, 6, 2, 100–105,weblink 30 November 2018, 10.7916/D8DR35JQ,
  • JOURNAL, 2004, Gradstein, F. M., Ogg, J. G., A Geologic Time scale 2004 – Why, How and Where Next!, Lethaia, 37, 2, 175–181,weblink 30 November 2018, 10.1080/00241160410006483,
  • BOOK, 2004, Gradstein, Felix M., Ogg, James G., Smith, Alan G., A Geologic Time Scale 2004,weblink Cambridge, UK, Cambridge University Press, 978-0-521-78142-8, 18 November 2011,
  • JOURNAL, June 2004, Gradstein, Felix M., Ogg, James G., Smith, Alan G., Bleeker, Wouter, Laurens, Lucas, J., A new Geologic Time Scale, with special reference to Precambrian and Neogene, Episodes, 27, 2,weblink 83–100, 18 November 2011,
  • WEB,weblink Ialenti, Vincent, Embracing 'Deep Time' Thinking., NPR Cosmos & Culture,
  • WEB,weblink Ialenti, Vincent, Pondering 'Deep Time' Could Inspire New Ways To View Climate Change., NPR Cosmos & Culture,
  • JOURNAL, 30 July 2004, Andrew H. Knoll, Knoll, Andrew H., Walter, Malcolm R., Narbonne, Guy M., Christie-Blick, Nicholas, A New Period for the Geologic Time Scale, Science (journal), Science, 305, 5684, 621–622,weblink 10.1126/science.1098803, 18 November 2011, 15286353,
  • BOOK, 2010, Levin, Harold L., Time and Geology,weblink The Earth Through Time,weblink Hoboken, New Jersey, John Wiley & Sons, 978-0-470-38774-0, 18 November 2011,
  • BOOK, Montenari, Michael, 2016, Stratigraphy and Timescales, 1st, Amsterdam, Academic Press (Elsevier), 978-0-12-811549-7,

External links

{{Commons category|Geologic time scale}} {{Geological history}}{{Navboxes|list={{Time topics}}{{Time measurement and standards}}{{Big History}}{{Chronology}}{{Earth}}}}

- content above as imported from Wikipedia
- "geologic time scale" does not exist on GetWiki (yet)
- time: 3:21am EDT - Wed, Jul 24 2019
[ this remote article is provided by Wikipedia ]
LATEST EDITS [ see all ]
Eastern Philosophy
History of Philosophy
M.R.M. Parrott