Diagram of geological time scale.
The geological time scale is used by geologists and other scientists to describe the timing and relationships between events that have occurred during the history of Earth. A geologist is a contributor to the Science of Geology, studying the physical structure and processes of the Earth and planets of the solar system A scientist, in the broadest sense refers to any person that engages in a systematic activity to acquire Knowledge or an individual that engages in such practices The history of Earth covers approximately 46 billion years (4567000000 years from Earth ’s formation out of the Solar nebula to the present The table of geologic periods presented here agrees with the dates and nomenclature proposed by the International Commission on Stratigraphy, and uses the standard color codes of the United States Geological Survey. The International Commission on Stratigraphy (ICS, sometimes referred to by the unofficial " International Stratigraphic Commission " is a daughter or major Subcommittee The United States Geological Survey ( USGS) is a scientific agency of the United States government.
Evidence from radiometric dating indicates that the Earth is about 4. Radiometric dating (often called radioactive dating) is a technique used to date materials usually based on a comparison between the observed abundance of a naturally occurring Modern geologists and Geophysicists consider the age of Earth to be around 4 570 billion years old. The geological or deep time of Earth's past has been organized into various units according to events which took place in each period. Deep time is the concept of geologic time first recognized in the 11th century by the Persian geologist and Polymath, Avicenna (Ibn Sina 973-1037 Different spans of time on the time scale are usually delimited by major geological or paleontological events, such as mass extinctions. Geology (from Greek γη gê, "earth" and λόγος Logos, "speech" lit Palaeontology redirects here For the Scientific journal, see Palaeontology (journal. An extinction event (also known as mass extinction; extinction-level event, ELE is a sharp decrease in the number of Species in a relatively short period For example, the boundary between the Cretaceous period and the Paleogene period is defined by the extinction event, known as the Cretaceous–Tertiary extinction event, that marked the demise of the dinosaurs and of many marine species. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of The Paleogene (alternatively Palaeogene) is a geologic period and system that began 65 An extinction event (also known as mass extinction; extinction-level event, ELE is a sharp decrease in the number of Species in a relatively short period The Cretaceous–Tertiary extinction event, which occurred approximately ( Ma) was a large-scale mass extinction of animal and plant species in a geologically In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. Older periods which predate the reliable fossil record are defined by absolute age.
Contents |
Graphical timelines
The second and third timelines are each subsections of their preceding timeline as indicated by asterisks.
The Holocene (the latest epoch) is too small to be shown clearly on this timeline. The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC
Terminology
The largest defined unit of time is the supereon composed of Eons. Eons are divided into Eras, which are in turn divided into Periods, Epochs and Stages. The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other At the same time paleontologists define a system of faunal stages, of varying lengths, based on changes in the observed fossil assemblages. In many cases, such faunal stages have been adopted in building the geological nomenclature, though in general there are far more recognized faunal stages than defined geological time units.
Geologists tend to talk in terms of Upper/Late, Lower/Early and Middle parts of periods and other units , such as "Upper Jurassic", and "Middle Cambrian". A geologist is a contributor to the Science of Geology, studying the physical structure and processes of the Earth and planets of the solar system The Jurassic is a geologic period and system that extends from about Ma (million years ago to Ma that is from the end of the Triassic to the beginning The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with Upper, Middle, and Lower are terms applied to the rocks themselves, as in "Upper Jurassic sandstone," while Late, Middle, and Early are applied to time, as in "Early Jurassic deposition" or "fossils of Early Jurassic age. Sandstone is a Sedimentary rock composed mainly of Sand -size Mineral or rock grains. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. " The adjectives are capitalized when the subdivision is formally recognized, and lower case when not; thus "early Miocene" but "Early Jurassic. " Because geologic units occurring at the same time but from different parts of the world can often look different and contain different fossils, there are many examples where the same period was historically given different names in different locales. For example, in North America the Lower Cambrian is referred to as the Waucoban series that is then subdivided into zones based on trilobites. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. The same timespan is split into Tommotian, Atdabanian and Botomian stages in East Asia and Siberia. The Tommotian Age, named after the Mollusc Tommotia, which began approx Siberia (Сиби́рь Sibir) is the name given to the vast region constituting almost all of Northern Asia and for the most part currently serving 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.
History of the time scale
Earth history mapped to 24 hours
The principles underlying geologic (geological) time scales were laid down by Nicholas Steno in the late 17th century. The history of geology is concerned with the development of the natural science of geology The history of Paleontology traces the effort to understand the history of life on Earth by studying the Fossil record left behind by living organisms Nicolas Steno ( Danish: Niels Stensen; Latinized to Nicolaus Stenonis) ( January 10, 1638 - November 25, Steno argued that rock layers (or strata) are laid down in succession, and that each represents a "slice" of time. He also formulated the principle of superposition, which states that any given stratum is probably older than those above it and younger than those below it. The law of superposition (or the principle of superposition) is a key axiom based on observations of Natural history that is a foundational principle of sedimentary While Steno's principles were simple, applying them to real rocks proved complex. Over the course of the 18th century geologists realized that:
- Sequences of strata were often eroded, distorted, tilted, or even inverted after deposition;
- Strata laid down at the same time in different areas could have entirely different appearances;
- The strata of any given area represented only part of the Earth's long history. Deposition is the geological process by which material is added to a Landform or land mass
A comparative geological timescale
The first serious attempts to formulate a geological time scale that could be applied anywhere on Earth took place in the late 18th century. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 The most influential of those early attempts (championed by Abraham Werner, among others) divided the rocks of the Earth's crust into four types: Primary, Secondary, Tertiary, and Quaternary. Abraham Gottlob Werner ( September 25, 1749 &ndash June 30, 1817) was a German Geologist who set out a now obsolete theory 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 Paleocene-Pliocene) and "Quaternary" (now Pleistocene-Holocene) remained in use as names of geological periods well into the 20th century.
In opposition to the then-popular Neptunist theories expounded by Werner (that all rocks had precipitated out of a single enormous flood), a major shift in thinking came with the reading by James Hutton of his Theory of the Earth; or, an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the Globe before the Royal Society of Edinburgh in March and April 1785, events which "as things appear from the perspective of the twentieth century, James Hutton in those reading became the founder of modern geology"[1] What Hutton proposed was that the interior of the 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. Neptunism is a discredited and Obsolete scientific theory of Geology proposed by Abraham Werner in the late 18th century that proposed rocks James Hutton MD (3 June 1726 OS (14 June 1726 NS) Edinburgh 26 March 1797 was a Scottish Geologist, The Royal Society of Edinburgh is Scotland 's National academy of science and letters This theory was dubbed "Plutonist" in contrast to the flood-oriented theory.
The identification of strata by the fossils they contained, pioneered by William Smith, Georges Cuvier, Jean d'Omalius d'Halloy and Alexandre Brogniart in the early 19th century, enabled geologists to divide Earth history more precisely. William Smith ( March 23 1769 &ndash August 28 1839) was an English Geologist, credited with creating the first nationwide Baron Georges Léopold Chrétien Frédéric Dagobert Cuvier ( August 23 1769 &ndash May 13, 1832) was a French naturalist Jean Baptiste Julien d'Omalius d'Halloy (1783-1875 was a Belgian Geologist. Alexandre Brongniart (1770 &ndash 1847 was a French Chemist, Mineralogist, and Zoologist, who collaborated with Georges Cuvier on 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 geological periods still used today.
The process was dominated by British geologists, and the names of the periods reflect that dominance. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located The "Cambrian," (the Roman name for Wales) and the "Ordovician," and "Silurian", named after ancient Welsh tribes, were periods defined using stratigraphic sequences from Wales. The Welsh people ( Welsh: Cymro ("Welshman" Cymraes ("Welsh woman" Cymry ("Welshmen/women" Cymry [2] The "Devonian" was named for the English county of Devon, and the name "Carboniferous" was simply an adaptation of "the Coal Measures," the old British geologists' term for the same set of strata. England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland The counties of England are territorial divisions of England for the purposes of administrative political and geographical demarcation Devon is a large county in the South West of England. The county is also referred to as Devonshire, but that is an entirely unofficial name The "Permian" was named after Perm, Russia, because it was defined using strata in that region by a Scottish geologist Roderick Murchison. Perm (Пермь pʲɛrmʲ is a city and administrative center of Perm Krai, Russia. Russia (Россия Rossiya) or the Russian Federation ( Rossiyskaya Federatsiya) is a transcontinental Country extending Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. Sir Roderick Impey Murchison 1st Baronet KCB FRS ( 19 February, 1792 &ndash 22 October, 1871) was an influential 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 trias meaning triad) —red beds, capped by chalk, followed by black shales— that are found throughout Germany and Northwest Europe, called the 'Trias'. Dr Friedrich August von Alberti ( September 4, 1795 &mdash September 12, 1878) was a German Geologist whose ground-breaking Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The term red beds usually refers to strata of reddish -colored sedimentary rocks such as Sandstone, Siltstone or Shale that Chalk (ʧɔːk is a soft white porous Sedimentary rock, a form of Limestone composed of the Mineral Calcite. Shale (also called mudstone) is a fine-grained Sedimentary rock whose original constituents were Clay minerals or Muds It is characterized by Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. North-West Europe is a term that refers to a northern area of Western Europe, although the exact area or countries it comprises varies The "Jurassic" was named by a French geologist Alexandre Brogniart for the extensive marine limestone exposures of the Jura Mountains. This article is about the country For a topic outline on this subject see List of basic France topics. Alexandre Brongniart (1770 &ndash 1847 was a French Chemist, Mineralogist, and Zoologist, who collaborated with Georges Cuvier on Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 The Jura Mountains are a small Mountain range located north of the Alps, separating the Rhine and Rhone rivers and forming part of The "Cretaceous" (from Latin creta meaning 'chalk') as a separate period was first defined by a Belgian geologist Jean d'Omalius d'Halloy in 1822, using strata in the Paris basin[3] and named for the extensive beds of chalk (calcium carbonate deposited by the shells of marine invertebrates). Chalk (ʧɔːk is a soft white porous Sedimentary rock, a form of Limestone composed of the Mineral Calcite. The Kingdom of Belgium is a Country in northwest Europe. It is a founding member of the European Union and hosts its headquarters as well as those Jean Baptiste Julien d'Omalius d'Halloy (1783-1875 was a Belgian Geologist. The Paris Basin is one of the major geological regions of France having developed since the Triassic on a basement formed by the Variscan orogeny. Calcium carbonate is a Chemical compound with the Chemical formula Ca[[Carbon C]] O 3 An invertebrate is an Animal lacking a Vertebral column. The group includes 98% of all animal Species — all animals except those in the Chordate
British geologists were also responsible for the grouping of periods into Eras and the subdivision of the Tertiary and Quaternary periods into epochs.
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 various kinds of rates of change used in estimation were highly variable. William Smith ( March 23 1769 &ndash August 28 1839) was an English Geologist, credited with creating the first nationwide Sir Charles Lyell 1st Baronet, KT, FRS (14 November 1797 &ndash 22 February 1875 was a Scottish Lawyer, Geologist, and protagonist In Geology and related fields a stratum (plural strata) is a layer of rock or Soil with internally consistent characteristics that distinguishes While creationists had been proposing dates of around six or seven thousand years for the age of the Earth based on the Bible, early geologists were suggesting millions of years for geologic periods with some even suggesting a virtually infinite age for the Earth. "Creationism" can also refer to Creation myths in general or to a concept about the origin of the soul. Modern geologists and Geophysicists consider the age of Earth to be around 4 Etymology According to the Online Etymology Dictionary, the word bible is from Latin biblia, traced from the same word through Medieval Latin and Late Latin 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. Palaeontology redirects here For the Scientific journal, see Palaeontology (journal. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Weathering is the decomposition of earth rocks, Soils and their Minerals through direct contact with the planet's Atmosphere. Erosion is the carrying away or displacement of solids ( Sediment, Soil, rock and other particles usually by the agents of currents such as wind Sedimentation describes the motion of Molecules in Solutions or particles in suspensions in response to an external force such as gravity Lithification (from the Greek word lithos meaning 'rock' and the Latin -derived suffix -ific) is the process in which Sediments compact 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 (pioneered by such geologists as Arthur Holmes) which allowed for more precise absolute dating of rocks, the ages of various rock strata and the age of the Earth were the subject of considerable debate. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. Radiometric dating (often called radioactive dating) is a technique used to date materials usually based on a comparison between the observed abundance of a naturally occurring Arthur Holmes ( January 14 1890 &ndash September 20 1965) was a British Geologist. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001
In 1977, the Global Commission on Stratigraphy (now the International Commission on Stratigraphy) started an effort to define global references (Global Boundary Stratotype Sections and Points) for geologic periods and faunal stages. The International Commission on Stratigraphy (ICS, sometimes referred to by the unofficial " International Stratigraphic Commission " is a daughter or major Subcommittee A Global Boundary Stratotype Section and Point, abbreviated GSSP, is an internationally agreed upon stratigraphic section which serves as the reference section for The commission's most recent work is described in the 2004 geologic time scale of Gradstein et al. [4]. A UML model for how the timescale is structured, relating it to the GSSP, is also available[5].
Table of geologic time
The following table summarizes the major events and characteristics of the periods of time making up the geologic time scale. As above, this time scale is based on the International Commission on Stratigraphy. (See lunar geologic timescale for a discussion of the geologic subdivisions of Earth's moon. The lunar geologic timescale (or selenologic timescale) divides the history of Earth 's moon into five generally recognized geologic periods the Copernican ) The height of each table entry does not correspond to the duration of each subdivision of time.
| Supereon | Eon | Era | Period[6] | Series / Epoch | Faunal stage[7] / Geologic age | Major events | Start, million years ago[7] |
|---|---|---|---|---|---|---|---|
| Phanerozoic | Cenozoic[8] | Neogene[8] | Holocene | Quaternary | The last glacial period ends and rise of human civilization. The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other The Phanerozoic (occasionally Phanaerozoic) Eon is the current eon in the Geologic timescale, and the one during which abundant animal life has existed The Cenozoic (also Caenozoic or Cainozoic) Era (ˌsiːnəˈzoʊɪk/ /ˌsɛn- (meaning "new life" ( Greek ( kainos) "new" The Neogene is a geologic period and system starting 2303 ± 0 The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC Overview The term Quaternary ("fourth" was proposed by Giovanni Arduino in 1759 for alluvial deposits in the Po river valley in northern "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period A Civilization is a society in which large numbers of people share a variety of common elements Quaternary Ice Age recedes, and the current interglacial begins. An interglacial is a geological interval of warmer global average temperature that separates Glacial periods within an Ice age. Younger Dryas cold spell occurs, Sahara Desert forms from savannah, and agriculture begins, allowing humans to build cities. The Younger Dryas Stadial, named after the alpine / tundra wildflower Dryas octopetala, and also referred to as the Big Freeze, was a brief (approximately The Sahara (الصحراء الكبرى aṣ-ṣaḥrā´ al-kubra, "The Great Desert" is the world's largest hot Desert and the world's second largest Agriculture refers to the production of goods through the growing of plants and fungi and the raising of domesticated Animals The study of agriculture A city is an Urban area with a large Population and a particular Administrative, Legal, or Historical status Paleolithic/Neolithic (Stone Age) cultures begin around 10,000 BC, giving way to Copper Age (3500 BC) and Bronze Age (2500 BC). The term Paleolithic (or Palaeolithic) (from Greek παλαιός palaios, " Old " and λίθος Lithos, "stone" The Neolithic (from Greek νεολιθικός — neolithikos from νέος neos, "new" + λίθος lithos The Stone Age is a broad prehistoric time period during which Humans widely used stone for toolmaking The Chalcolithic (Greek khalkos + lithos ' Copper stone' period or Copper Age period known as the '''Eneolithic''' ('''Æneolithic''' is a The term Bronze Age refers to a period in human cultural development when the most advanced Metalworking (at least in systematic and widespread use included techniques for 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 Ancient Rome and even to the Middle Ages and present day. This article is about the archaeological period known as the Iron Age for the mythological Iron Age see Ages of Man. The synoptic table of the principal old world prehistoric cultures gives a rough picture of the relationships between the various principal cultures of Prehistory Classical antiquity (also the classical era or classical period) is a broad term for a long period of cultural History centered on the Mediterranean Ancient Rome was a Civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC For current events see PortalCurrent events The term " present day " is used to describe the rough period of Time that Also refer to the List of archaeological periods for clarification on early cultures and ages. Names for archaeological periods vary enormously from region to region Mount Tambora erupts in 1815, causing the Year Without a Summer (1816) in Europe and North America from a volcanic winter. Mount Tambora (or Tomboro) is an active Stratovolcano, also known as a Composite volcano, on Sumbawa island Indonesia. Year 1815 ( MDCCCXV) was a Common year starting on Sunday (link will display the full calendar of the Gregorian calendar (or a Common year The Year Without a Summer, also known as the Poverty Year, The Year There Was No Summer or Eighteen hundred and froze to death Year 1816 ( MDCCCXVI) was a Leap year starting on Monday (link will display the full calendar of the Gregorian calendar (or a Leap year A volcanic winter is the reduction in temperature caused by Volcanic ash and droplets of Sulfuric acid obscuring the Sun and lowering the Albedo atmospheric CO2 levels start creeping from 100 ppmv at the end of the last glaciation to the current level of 385 parts per million volume (ppmv), causing global warming and climate change, possibly from anthropogenic sources, such as the Industrial Revolution[9] | 0. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single "Parts-per" notation is used especially in Science and Engineering, to denote Ratios (relative proportions in measured quantities particularly Global warming is the increase in the average measured temperature of the Climate change is any long-term significant change in the “average weather” that a given region experiences National and international science academies and professional societies have assessed the current scientific opinion on climate change, in particular recent Global warming. Anthropogenic effects processes objects or materials are those that are derived from Human activities as opposed to those occurring in Natural environments without The Industrial Revolution was a period in the late 18th and early 19th centuries when major changes in agriculture manufacturing and transportation had a profound effect on the 011430 ± 0. 00013[8][10] | |
| Pleistocene | Late/Tyrrhenian Stage | Flourishing and then extinction of many large mammals (Pleistocene megafauna). The Pleistocene ('plaɪstəsin is the epoch from 18 million to 10000 years BP covering the world's recent period The Late Pleistocene (also known as Upper Pleistocene or the Tarantian) is a stage of the Pleistocene Epoch. This is a Geological time scale article for archaeologiy see Etruscan civilization The Tyrrhenian Stage is the last Faunal Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Pleistocene megafauna is the set of Species of large animals &mdash Mammals Birds and Reptiles &mdash that lived on Earth during the Pleistocene Evolution of anatomically modern humans. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Quaternary Ice Age continues with glaciations and interstadials (and the accompanying fluctuations from 100 to 300 ppmv in atmospheric Carbon Dioxide levels[9]), further intensification of Icehouse Earth conditions, roughly 1. "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period A glacial period is an interval of time within an Ice age that is marked by colder temperatures and Glacier advances A stadial is a period of colder Temperatures during an Interglacial, of insufficient duration or intensity to be considered a Glaciation, or glacial period Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years 6 MYA[11]. Last glacial maximum (30,000 years ago), last glacial period (18,000-15,000 years ago). The Last Glacial Maximum (LGM refers to the time of maximum extent of the Ice sheets during the last Glaciation (the Würm or Wisconsin glaciation) approximately Before Present (BP years are a time scale used in Archaeology, Geology, and other scientific disciplines to specify when events in the past occurred "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period Dawn of human stone-age cultures, with increasing technical complexity than previous ice age cultures, such as engravings and clay statues (Venus of Lespugue), particularly in the Mediterranean and Europe. The Lower Paleolithic (or Lower Palaeolithic) is the earliest subdivision of the Paleolithic or Old Stone Age. The Middle Paleolithic (or Middle Palaeolithic) is the second subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe Africa The Venus of Lespugue is a Venus figurine, a Statuette of a nude female figure from approximately 25000 BC. Lake Toba supervolcano erupts 75,000 years before present, causing a volcanic winter and pushes humanity to the brink of extinction. Lake Toba ( Danau Toba) is a Lake and Supervolcano, 100 km long and 30 km wide and 505 m A supervolcano or super volcanic eruption is a Volcanic eruption which is Orders of magnitude greater than any volcano in historic times (generally accepted to be A volcanic winter is the reduction in temperature caused by Volcanic ash and droplets of Sulfuric acid obscuring the Sun and lowering the Albedo According to the Toba catastrophe theory, 70000 to 75000 years ago a supervolcanic event at Lake Toba, on Sumatra, reduced the world's human population | 0. 126 ± 0. 005* | ||||
| Middle | 0. So far the Pleistocene Series is not subdivided into formal units (i 500? | ||||||
| Early | 1. Early Pleistocene (also known as Lower Pleistocene, or Calabrian) is a subdivision of the Pleistocene Epoch of the Geologic time scale 806 ± 0. 005* | ||||||
| Gelasian | 2. The Gelasian is a stage whose belonging to either the Pliocene or the Pleistocene Epochs is currently discussed 588 ± 0. 005* | ||||||
| Pliocene | Piacenzian/Blancan | Intensification of present Icehouse conditions, Present (Quaternary) ice age begins roughly 2. The Pliocene epoch (spelled Pleiocene in some older texts is the period in the Geologic timescale that extends Piacenzian (also known as Astian, Redonian, or Romanian) is a Age of the Pliocene Epoch. The Blancan North American Stage on the Geologic timescale is the North American Faunal stage according to the North American Land Mammal Ages chronology The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years 58 MYA; cool and dry climate. Climate encompasses the temperatures humidity rainfall atmospheric particle count and numerous other meteorogical factors in a given region over long periods of Australopithecines, many of the existing genera of mammals, and recent mollusks appear. The term australopithecine refers to two very closely related genera within the Hominina subtribe of the Hominini tribe. Molluscs are animals belonging to the phylum Mollusca. There are around 250000 extant Species within the phylum with an estimated 70000 Homo habilis appears. Homo habilis (ˈhoʊmoʊ ˈhæbəlɪs ("handy man" "skillful person" is a Species of the genus Homo, which lived | 3. 600 ± 0. 005* | ||||
| Zanclean | 5. In the Geologic time scale, the Zanclean (also known as Tabianian, Dacian) is the Age which makes up the Early Pliocene 332 ± 0. 005* | ||||||
| Miocene | Messinian | Moderate Icehouse climate, puncuated by ice ages; Orogeny in northern hemisphere. The Miocene is a geological epoch of the Neogene period and extends from about 23 Messinian is the last Age of the Miocene epoch. It spans the time between 7 The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and Northern Hemisphere is the half of a Planet that is North of the Equator —the word hemisphere literally means 'half ball' Modern mammal and bird families became recognizable. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Horses and mastodons diverse. Equidae is the family of horse-like animals which belong to the order Perissodactyla. Mastodons or Mastodonts (from Greek μαστός and οδούς, meaning " Nipple tooth" are members of the extinct Grasses become ubiquitous. Grass is the common word that generally describes Monocotyledonous green Plants The family Gramineae ( Poaceae) are the "true grasses" and include First apes appear (for reference see the article: "Sahelanthropus tchadensis"). Sahelanthropus tchadensis is a Fossil Ape that lived approximately 7-6 Million years ago. Kaikoura Orogeny forms Southern Alps in New Zealand, continues today. The Kaikoura Orogeny is a New Zealand Orogeny that has given birth to the Southern Alps. The Southern Alps is a Mountain range which runs along the western side of the South Island of New Zealand. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island Orogeny of the Alps in Europe slows, but continues to this day. Carpathean orogeny forms Carpathian Mountains in Central and Eastern Europe. The Carpathian Mountains or Carpathians (Carpaţi Czech, Polish and Slovak: Karpaty; Ukrainian: Карпати Central Europe is the Region lying between the variously and vaguely defined areas of Eastern and Eastern Europe is a general term that refers to the Geopolitical region encompassing the easternmost part of the European continent. Hellenic orogeny in Greece and Aegean Sea slows, but continues to this day. Middle Miocene Disruption occurs. The term Middle Miocene disruption alternatively the Middle Miocene extinction or Middle Miocene extinction peak refers to a wave of extinctions of terrestrial Widespread forests slowly draw in massive amounts of atmospheric Carbon Dioxide, gradually lowering the level atmospheric CO2 from 650 ppmv down to around 100 ppmv[9]. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single | 7. 246 ± 0. 05* | ||||
| Tortonian | 11. Tortonian is a Age of the late Miocene epoch that spans the time between 11 608 ± 0. 05* | ||||||
| Burdigalian | 13. Burdigalian is a Age of the early Miocene Epoch. It spans the time between 20 65 ± 0. 05* | ||||||
| Serravallian | 15. Serravallian is a Age of the middle Miocene epoch that spans the time between 13 97 ± 0. 05* | ||||||
| Langhian | 20. Langhian is the older ICS Age of the Middle Miocene epoch. It spans the time between 15 43 ± 0. 05* | ||||||
| Aquitanian | 23. 03 ± 0. 05* | ||||||
| Paleogene[8] | Oligocene | Chattian | Warm but cooling climate, moving towards Icehouse; Rapid evolution and diversification of fauna, especially mammals. The Paleogene (alternatively Palaeogene) is a geologic period and system that began 65 The Oligocene is a geologic epoch of the Paleogene period and extends from about 33 The Chattian (also known as Chickasawhayan or Late Oligocene) is the second and final of two stages of the Oligocene Epoch. The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years eVolution is the third Album by eLDee, it was due to be released in 2008 Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Major evolution and dispersal of modern types of flowering plants | 28. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group 4 ± 0. 1* | |||
| Rupelian | 33. The Rupelian (also known as Stampian, Tongrian, Latdorfian, Vicksburgian, or Early Oligocene) is the first of two stages 9 ± 0. 1* | ||||||
| Eocene | Priabonian | Moderate, cooling climate. The Eocene epoch (558 ± 02 - 339 ± 01 Ma) is a major division of the Geologic timescale and the second epoch of the Palaeogene period in The Priabonian (also known as Jacksonian or Runangan) is the final stage of the Eocene Epoch. The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years Archaic mammals (e. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands g. Creodonts, Condylarths, Uintatheres, etc) flourish and continue to develop during the epoch. The creodonts are an Extinct order of Mammals that lived from the Paleocene to the Miocene epochs Condylarthra is an order of extinct Placental Mammals known primarily from the Paleocene and Eocene epochs The Uintatheriidae is a family of extinct Mammals that includes Uintatherium. Appearance of several "modern" mammal families. Primitive whales diversify. The Order Cetacea (sɪˈteɪʃiə L cetus, whale includes Whales Dolphins and Porpoises Cetus is First grasses. Grass is the common word that generally describes Monocotyledonous green Plants The family Gramineae ( Poaceae) are the "true grasses" and include 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[9], lowering it from 3800 ppmv down to 650 ppmv. An ice cap is an Ice mass that covers less than 50 000 km² of land area (usually covering a highland area The Azolla event occurred in the middle Eocene period around, when blooms of the freshwater Fern Azolla occurred in the Arctic Ocean An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years "Ocean Floor" redirects here For the 2001 song by Audio Adrenaline, see Lift (Audio Adrenaline album. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single "Parts-per" notation is used especially in Science and Engineering, to denote Ratios (relative proportions in measured quantities particularly End of Laramide and Sevier Orogenies of the Rocky Mountains in North America. The Laramide orogeny was a period of Mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago and ended The Sevier orogeny was a mountain-building event that affected western North America from Canada to the north to Mexico to the south Mountain peaks of the Rocky Mountains The Rocky Mountains, often called the Rockies, are a Mountain range in western North America. Orogeny of the Alps in Europe begins. Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and Hellenic Orogeny begins in Greece and Aegean Sea. Greece (Ελλάδα transliterated: Elláda, historically, Ellás,) officially the Hellenic Republic (Ελληνική Δημοκρατία Etymology In ancient times there were various explanations for the name Aegean. | 37. 2 ± 0. 1* | ||||
| Bartonian | 40. The Bartonian (also known as the Auversian) is a stage of the middle Eocene Epoch. 4 ± 0. 2* | ||||||
| Lutetian | 48. The Lutetian is a stage of the Eocene Epoch. It spans the time between 48 6 ± 0. 2* | ||||||
| Ypresian | 55. The Ypresian is the first stage of the Eocene Epoch and usually corresponds to the Early Eocene subepoch though sometimes the Lutetian 8 ± 0. 2* | ||||||
| Paleocene | Thanetian | Climate tropical. The Paleocene or Palaeocene, "early dawn of the recent" is a geologic epoch that lasted from 65 The Thanetian (also known as the Landenian or Heersian) is the last stage of the Paleocene Epoch, corresponding to the Late Paleocene The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years Modern plants appear; Mammals diversify into a number of primitive lineages following the extinction of the dinosaurs. Plants are living Organisms belonging to the kingdom Plantae. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands First large mammals (up to bear or small hippo size). Alpine orogeny in Europe and Asia begins. The Alpine orogeny (sometimes also called Alpide orogeny) is an orogenic phase in the Tertiary that formed the mountain ranges of the Alpide belt Indian Subcontinent collides with Asia 55 MYA[11], Himalayan Orogeny starts between 52 and 48 MYA. This article deals with the geophysical region in Asia For geopolitical treatments see South Asia. The geology of the Himalaya is a record of the most dramatic and visible creations of modern Plate tectonic forces | 58. 7 ± 0. 2* | ||||
| Selandian | 61. Selandian or Middle Paleocene is a stage of the Paleocene Epoch. 7 ± 0. 3* | ||||||
| Danian | 65. The Danian (also known as the Montian) is the first stage of the Paleocene Epoch, making up the Early Paleocene sub-epoch 5 ± 0. 3* | ||||||
| Mesozoic | Cretaceous | Upper/Late | Maastrichtian | Flowering plants proliferate, along with new types of insects. The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of Late Cretaceous (100mya - 65mya refers to the second half of the Cretaceous Period, named after the famous white Chalk cliffs of southern England The Maastrichtian is the last stage of the Cretaceous period, and therefore of the Mesozoic era. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described More modern teleost fish begin to appear. Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes Ammonites, belemnites, rudist bivalves, echinoids and sponges all common. Ammonites are an extinct group of marine animals of the subclass Ammonoidea in the class Cephalopoda phylum Belemnites (or belemnoids are an extinct group of marine Cephalopod, very similar in many ways to the modern Squid and closely related to the modern Cuttlefish Rudists are a group of bizarrely shaped marine Heterodont Bivalves that arose during the Jurassic, and became so diverse during the Bivalves are Molluscs belonging to the class Bivalvia. They have two-part shells and typically both valves are symmetrical along the hinge line Sea urchins are small globular spiny sea cat animals composing most of class Echinoidea. The sponges or poriferans (from Latin porus "pore" and ferre "to bear" are Animals 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. Tyrannosauridae (or tyrannosaurids, meaning "tyrant lizards" is a family of Coelurosaurian Theropod Dinosaurs which Titanosaurs (members of the groups Titanosauria and/or Titanosauroidea) were a diverse group of sauropod Dinosaurs which included Saltasaurus Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus Ceratopsidae (sometimes spelled Ceratopidae) is a speciose group of Marginocephalian Dinosaurs including Triceratops and Styracosaurus Crocodilia is an order of large Reptiles that appeared about 84 million years ago in the late Cretaceous Period ( Campanian stage Mosasaurs (from Latin Mosa meaning the ' Meuse river ' in the Netherlands and Greek sauros meaning 'lizard' were serpentine marine Sharks ( Superorder Selachimorpha) are a type of Fish with a full cartilaginous Skeleton and a highly streamlined body Primitive birds gradually replace pterosaurs. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. For other meanings see Pterodactyl (disambiguation. Pterosaurs (ˈtɛrəsɔr from the Greek πτερόσαυρος pterosauros Monotremes, marsupials and placental mammals appear. Monotremes (from the Greek monos 'single' + trema 'hole' referring to the Cloaca) are Mammals that lay eggs ( Prototheria) instead Marsupials are an Infraclass of Mammals characterized by a distinctive pouch (called the marsupium) in which females carry their young through See also Evolution of mammals Eutheria ("true beast" are a group of Mammals consisting of Placental mammals plus all extinct Mammals Break up of Gondwana. Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Beginning of Laramide and Sevier Orogenies of the Rocky Mountains. The Laramide orogeny was a period of Mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago and ended The Sevier orogeny was a mountain-building event that affected western North America from Canada to the north to Mexico to the south Mountain peaks of the Rocky Mountains The Rocky Mountains, often called the Rockies, are a Mountain range in western North America. Atmospheric Carbon Dioxide close to present-day levels. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single | 70. 6 ± 0. 6* | ||
| Campanian | 83. The Campanian is a stage on the Geologic time scale occurring from 83 5 ± 0. 7* | ||||||
| Santonian | 85. The Santonian is a Faunal stage of the Late Cretaceous Epoch. 8 ± 0. 7* | ||||||
| Coniacian | 89. The Coniacian is a stage of the Late Cretaceous Epoch. It spans the time between 89 3 ± 1. 0* | ||||||
| Turonian | 93. The Turonian is a stage of the Late Cretaceous Epoch. It spans the time between 93 5 ± 0. 8* | ||||||
| Cenomanian | 99. |-|The Cenomanian age (also known as Woodbinian by the [[ICS]] is the first or earliest or oldest Geochronological "geologic age" 6 ± 0. 9* | ||||||
| Lower/Early | Albian | 112. The Early Cretaceous ( timestratigraphic name or the Lower Cretaceous ( logstratigraphic name is the earlier of the two major divisions of the Cretaceous Albian ( French Albion, from Alba = Aube in France) is a stage of the Cretaceous period. 0 ± 1. 0* | |||||
| Aptian | 125. Aptian stage is a Faunal stage of the Early Cretaceous epoch in the Geologic timescale, that extends from 125 0 ± 1. 0* | ||||||
| Barremian | 130. The Barremian Faunal stage was a period of geological time between 130 0 ± 1. 5* | ||||||
| Hauterivian | 136. The Hauterivian is a stage of the Early Cretaceous Epoch. It spans the time between 136 4 ± 2. 0* | ||||||
| Valanginian | 140. In the Geologic timescale, Valanginian is a stage of the Early Cretaceous epoch. 2 ± 3. 0* | ||||||
| Berriasian | 145. In the Geologic timescale, Berriasian is a stage of the Early Cretaceous epoch, and the first of the entire Cretaceous period 5 ± 4. 0* | ||||||
| Jurassic | Upper/Late | Tithonian | Gymnosperms (especially conifers, Bennettitales and cycads) and ferns common. The Jurassic is a geologic period and system that extends from about Ma (million years ago to Ma that is from the end of the Triassic to the beginning The Late Jurassic (or Malm) Epoch of the Jurassic Period is the unit of geologic time from 161 The Tithonian is the final stage of the Late Jurassic Epoch. It spans the time between 150 Gymnosperm (Gymnospermae are a group of Spermatophyte seed-bearing Plants with Ovules on the edge or blade of an open Sporophyll, which are Bennettitales (the cycadeoids) is an extinct order of seed plants that first appeared in the Triassic period and became extinct toward Cycads are a group of Seed plants characterized by a large crown of compound leaves and a stout trunk. A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Many types of dinosaurs, such as sauropods, carnosaurs, and stegosaurs. Sauropoda (sɔˈrɒpədə or the sauropods (/ˈsɔroʊpɒd/ are a suborder or infraorder of the Saurischian ("lizard-hipped" Carnosauria is a group of large Predatory Dinosaurs that lived during the Jurassic and Cretaceous periods Known colloquially as stegosaurs the Stegosauria are a group of herbivorous Dinosaurs of the Jurassic and Early Cretaceous Periods Mammals common but small. First birds and lizards. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Squamata (scaled reptiles is the largest recent order of Reptiles including Lizards and Snakes Members of the order are distinguished by Ichthyosaurs and plesiosaurs diverse. Ichthyosaurs ( Greek for 'fish lizard' - ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' were giant Plesiosaurs (ˈpliːziəˌsɔɹ ( Greek: plesios/πλησιος meaning 'near' or 'close to' and sauros/σαυρος meaning Bivalves, Ammonites and belemnites abundant. Bivalves are Molluscs belonging to the class Bivalvia. They have two-part shells and typically both valves are symmetrical along the hinge line Ammonites are an extinct group of marine animals of the subclass Ammonoidea in the class Cephalopoda phylum Belemnites (or belemnoids are an extinct group of marine Cephalopod, very similar in many ways to the modern Squid and closely related to the modern Cuttlefish Sea urchins very common, along with crinoids, starfish, sponges, and terebratulid and rhynchonellid brachiopods. Sea urchins are small globular spiny sea cat animals composing most of class Echinoidea. Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the Echinoderms (phylum Echinodermata The sponges or poriferans (from Latin porus "pore" and ferre "to bear" are Animals Terebratulids are one of only two living orders of articulate Brachiopods the other being the Rhynchonellida. The Taxonomic order Rhynchonellida is one of the two main groups of living articulate Brachiopods the other being the order Terebratulida Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also Breakup of Pangaea into Gondwana and Laurasia. Pangaea, Pangæa or Pangea (pænˈdʒiːə from παν pan, meaning entire, and Γαῖα Gaea, meaning Earth in Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Laurasia (lɔˈreɪʃiə lɔˈreɪʒə was a Supercontinent that most recently existed as a part of the split of the Pangaean supercontinent in the late Mesozoic Nevadan orogeny in North America. The Nevadan Orogeny was a major Mountain building event that took place along the western edge of ancient North America between the Mid to Late Jurassic Rantigata and Cimmerian Orogenies taper off. The Rangitata Orogeny (an Orogeny named after the Rangitata River) was a long period of uplift and collision in New Zealand. The Cimmerian Orogeny, is an Orogeny that created mountain ranges that now lie in Central Asia Atmospheric Carbon Dioxide levels 4-5 times the present day levels (1200-1500 ppmv, compared to today's 385 ppmv[9]). | 150. 8 ± 4. 0* | |||
| Kimmeridgian | 155. The Kimmeridgian is a stage of the Late Jurassic Epoch. It spans the time between 155 7 ± 4. 0* | ||||||
| Oxfordian | 161. The Oxfordian stage is the first stage of the Late Jurassic Epoch. 2 ± 4. 0* | ||||||
| Middle | Callovian | 164. The Middle Jurassic, called the Dogger in the European system of classification is the second epoch of the Jurassic Period. The Callovian is a stage on the Geologic time scale occurring 164 7 ± 4. 0 | |||||
| Bathonian | 167. In the Geologic timescale the Bathonian epoch is a stage during the Middle Jurassic, of the Mesozoic era of the Phanerozoic 7 ± 3. 5* | ||||||
| Bajocian | 171. In the Geologic timescale, the Bajocian is an age of the Middle Jurassic epoch of the Jurassic period of the Mesozoic 6 ± 3. 0* | ||||||
| Aalenian | 175. The Aalenian (ɑːˈliːniən is a subdivision of the Middle Jurassic epoch of the Geologic timescale that extends from about 175 6 ± 2. 0* | ||||||
| Lower/Early | Toarcian | 183. For general context see Jurassic. The Early Jurassic (in geology referred to as the Lower Jurassic, originally (and still in Europe the The Toarcian Stage was the last Faunal stage of the Early Jurassic period 0 ± 1. 5* | |||||
| Pliensbachian | 189. The Pliensbachian (also known as Charmouthian) is a stage of the Early Jurassic Epoch. 6 ± 1. 5* | ||||||
| Sinemurian | 196. The Sinemurian is a stage of the Early Jurassic Epoch. It spans the time between 196 5 ± 1. 0* | ||||||
| Hettangian | 199. The Hettangian is the first stage of the Early Jurassic Epoch. 6 ± 0. 6* | ||||||
| Triassic | Upper/Late | Rhaetian | Archosaurs dominant on land as dinosaurs, in the oceans as Ichthyosaurs and nothosaurs, and in the air as pterosaurs. The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago The Late Triassic (also known as Upper Triassic, or Keuper) is the third and final of three epochs of the Triassic period. See Raetians for the Alpine people of antiquity See Romansh language for the Rhaetian language Archosaurs ( Greek for 'ruling lizards' are a group of Diapsid Reptiles represented by Modern birds and Crocodilians This group also Ichthyosaurs ( Greek for 'fish lizard' - ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' were giant Nothosaurs (order Nothosauroidea) were Triassic marine Sauropterygian Reptiles that may have lived like seals of today catching For other meanings see Pterodactyl (disambiguation. Pterosaurs (ˈtɛrəsɔr from the Greek πτερόσαυρος pterosauros cynodonts become smaller and more mammal-like, while first mammals and crocodilia appear. Cynodonts, or 'dog teeth' are a taxon of Therapsids which includes modern mammals and their extinct close relatives Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Crocodilia is an order of large Reptiles that appeared about 84 million years ago in the late Cretaceous Period ( Campanian stage Dicrodium flora common on land. Many large aquatic temnospondyl amphibians. Temnospondyli (from Greek τεμνειν temnein = "to cut" + σπονδυλως spondulos = "vertebra" are an important and extremely diverse Ceratitic ammonoids extremely common. Ammonites are an extinct group of marine animals of the subclass Ammonoidea in the class Cephalopoda phylum Modern corals and teleost fish appear, as do many modern insect clades. Scleractinia, also called Stony Corals, are exclusively marine animals they are very similar to Sea anemones but generate a hard skeleton Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described Andean Orogeny in South America. South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a Cimmerian Orogeny in Asia. The Cimmerian Orogeny, is an Orogeny that created mountain ranges that now lie in Central Asia Rangitata Orogeny begins in New Zealand. The Rangitata Orogeny (an Orogeny named after the Rangitata River) was a long period of uplift and collision in New Zealand. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island Hunter-Bowen Orogeny in Northern Australia, Queensland and New South Wales ends, (c. The term northern Australia is generally considered to include the States and territories of Australia of Queensland and the Northern Territory. Queensland is a state of Australia, occupying the north-eastern corner of the mainland continent 260-225 MYA) | 203. 6 ± 1. 5* | |||
| Norian | 216. The Norian Stage was a portion of the Triassic Geological period. 5 ± 2. 0* | ||||||
| Carnian | 228. The Carnian (less commonly Karnian) is the lowermost stage of the Upper Triassic series (or earliest age of the Late Triassic 0 ± 2. 0* | ||||||
| Middle | Ladinian | 237. The Middle Triassic (also known as Muschelkalk) is the second of three epochs of the Triassic period. The Ladinian (also known as the Falangian) is a stage of the Middle Triassic epoch. 0 ± 2. 0* | |||||
| Anisian | 245. In the Geologic timescale, the Anisian is the age of the Middle Triassic epoch and lasted from 245 million years ago until 237 million years 0 ± 1. 5* | ||||||
| Lower/Early ("Scythian") | Olenekian | 249. The Early Triassic (also known as Lower Triassic, Buntsandstein, or Scythian) is the first of three epochs of the Triassic The Olenekian (also known as the Yongningzhenian) is a stage of the Early Triassic epoch. 7 ± 1. 5* | |||||
| Induan | 251. The Induan (also known as the Feixianguanian) is the first stage of the Early Triassic epoch. 0 ± 0. 7* | ||||||
| Paleozoic | Permian | Lopingian | Changhsingian | Landmasses unite into supercontinent Pangaea, creating the Appalachians. The Paleozoic or Palaeozoic Era (from the Greek palaio (παλαιο "old" and zoe (ζωη "life" meaning "ancient life" The Permian is a geologic period and system that extends from 299 Not to be confused with Land mass. A landmass is a large continuous area of land. In Geology, a supercontinent is a Landmass comprising more than one Continental core or Craton. Pangaea, Pangæa or Pangea (pænˈdʒiːə from παν pan, meaning entire, and Γαῖα Gaea, meaning Earth in The Appalachian Mountains ( often called the Appalachians, are a vast system of mountains in eastern North America. End of Permo-Carboniferous glaciation. Synapsid reptiles (pelycosaurs and therapsids) become plentiful, while parareptiles and temnospondyl amphibians remain common. Synapsids ('fused arch' also known as theropsids ('beast face' are a class of Animals that includes Mammals and everything closer to mammals than Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers The pelycosaurs (from Greek πηλυξ pelyx meaning 'bowl' and σαυρος sauros meaning 'lizard' were primitive Late Paleozoic Therapsids are an order of Synapsids (Class Synapsida Traditionally synapsids were referred to as Reptiles and were known as Parareptilia ("at the side of reptiles" is a subclass or clade of Reptiles which are variously defined as an extinct group of primitive anapsids or a more cladistically correct Temnospondyli (from Greek τεμνειν temnein = "to cut" + σπονδυλως spondulos = "vertebra" are an important and extremely diverse Prehistoric amphibian Amphibians (class Amphibia such as Frogs Toads Salamanders Newts Gymnophiona, Sirens and In the mid-Permian, coal-age flora are replaced by cone-bearing gymnosperms (the first true seed plants) and by the first true mosses. A cone (in formal botanical usage Strobilus, plural strobili is an organ on Plants in the division Pinophyta ( Conifers Gymnosperm (Gymnospermae are a group of Spermatophyte seed-bearing Plants with Ovules on the edge or blade of an open Sporophyll, which are The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are Mosses are small soft Plants that are typically 1–10 cm (0 Beetles and flies evolve. Beetles are the group of Insects with the largest number of known Species. True flies are Insects of the Order Diptera ( Greek: di = two and pteron = wing possessing a single pair of Marine life flourishes in warm shallow reefs; productid and spiriferid brachiopods, bivalves, forams, and ammonoids all abundant. Spiriferida is an order of extinct articulate Brachiopod, Fossils of which are known for their long hinge-line which is often the widest part of the shell The Foraminifera, ("Hole Bearers" or forams for short are a large group of Amoeboid Protists with reticulating Pseudopods fine Orthocerida are an order of extinct Nautiloid Cephalopods that lived from the Early Ordovician (about 500 million years ago to the Late Permian Permian-Triassic extinction event occurs 251 mya: 95% of life on Earth becomes extinct, including all trilobites, graptolites, and blastoids. The Permian–Triassic (P–Tr extinction event, informally known as the Great Dying, was an Extinction event that occurred, and 70 percent of terrestrial Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Graptolites (Graptolithina are Fossil colonial Animals known chiefly from the Upper Cambrian through the Lower Carboniferous ( Mississippian Blastoids (class Blastoidea are an Extinct type of stemmed Echinoderm. Ouachita and Innuitian Orogenies in North America. The Ouachita orogeny was a mountain building event that resulted in the folding and faulting of strata currently exposed in the Ouachita Uralian Orogeny in Europe/Asia tapers off. Altaid orogeny in Asia. Hunter-Bowen Orogeny on Australian Continent begins, (c. 260-225 MYA). Forms the MacDonnell Ranges. The MacDonnell Ranges of the Northern Territory, are a 644 km (400 mile long series of mountain ranges located in the centre of Australia ( and consist of parallel | 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[12]/ Pennsyl- vanian |
Upper/Late | Gzhelian | Winged insects radiate suddenly; some (esp. The Carboniferous is a geologic period and system that extends from the end of the Devonian period about 359 The Pennsylvanian is a subperiod of the Carboniferous period lasting from roughly to Ma (million years ago The Late Pennsylvanian (its rocks belong to the Upper Pennsylvanian) is the third and final of three subepochs of the Pennsylvanian epoch of The Gzhelian Age is the last of four ages in the Pennsylvanian Epoch of the Carboniferous period. Pterygota is a subclass of Insects that includes the winged insects Protodonata and Palaeodictyoptera) are quite large. The Protodonata or Meganisoptera are an extinct order of very large to gigantic Palaeozoic ( Late Carboniferous to Late Permian) insects similar in appearance The Palaeodictyoptera are an extinct order of medium-sized to very large primitive Palaeozoic paleopterous insects characterised by beak-like mouthparts similarity between Amphibians common and diverse. Prehistoric amphibian Amphibians (class Amphibia such as Frogs Toads Salamanders Newts Gymnophiona, Sirens and First reptiles and coal forests (scale trees, ferns, club trees, giant horsetails, Cordaites, etc. Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers Lepidodendron (also known as the "Scale tree" is an Extinct Genus of primitive vascular arborescent ( Tree -like Plant Sigillaria is a genus of extinct spore-bearing arborescent (tree-like plants which flourished in the Late Carboniferous period but dwindled to extinction in the early Calamites is a genus of Extinct arborescent (tree-like horsetails to which the modern Horsetails (genus Equisetum) are closely The explosive is spelled Cordite. Cordaites is an important genus of extinct Gymnosperms which grew on wet ground similar to the Everglades ). Highest-ever atmospheric oxygen levels. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Goniatites, brachiopods, bryozoa, bivalves, and corals plentiful in the seas and oceans. Goniatites are an extinct group of ammonoid, which are shelled Cephalopods related to Squids Belemnites Octopuses Testate forams proliferate. The Foraminifera, ("Hole Bearers" or forams for short are a large group of Amoeboid Protists with reticulating Pseudopods fine Uralian Orogeny in Europe and Asia. | 303. 9 ± 0. 9* | |||
| Kasimovian | 306. The Kasimovian Age is the third of four ages in the Pennsylvanian Epoch of the Carboniferous period. 5 ± 1. 0* | ||||||
| Middle | Moscovian | 311. The Middle Pennsylvanian is the second of three subepochs of the Pennsylvanian epoch of the Carboniferous period. The Moscovian Age is the second of four ages in the Pennsylvanian Epoch of the Carboniferous period. 7 ± 1. 1* | |||||
| Lower/Early | Bashkirian | 318. The Early Pennsylvanian (also known as the Lower Pennsylvanian) is the first of three subepochs of the Pennsylvanian epoch of the Carboniferous The Bashkirian Age is the first of four ages in the Pennsylvanian Epoch of the Carboniferous period. 1 ± 1. 3* | |||||
| Carbon- iferous[12]/ Missis- sippian |
Upper/Late | Serpukhovian | Large primitive trees, first land vertebrates, and amphibious sea-scorpions live amid coal-forming coastal swamps. The Carboniferous is a geologic period and system that extends from the end of the Devonian period about 359 The Late Mississippian (also known as the Upper Mississippian) is the third and final of three subepochs of the Mississippian epoch of the The Serpukhovian age is the last of three ages in the Mississippian Epoch of the Carboniferous Period The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae It is the oldest extant (living Tetrapods ( Greek τετραποδη tetrapoda, Latin Quadruped, "four-footed" are Vertebrate Animals The eurypterids (sea scorpions include the largest known Arthropod that ever lived (with the possible exception of Arthropleuridae) Lobe-finned rhizodonts are dominant big fresh-water predators. Rhizodonts (Order Rhizodontida are an extinct group of predatory lobe-finned fishes In the oceans, early sharks are common and quite diverse; echinoderms (especially crinoids and blastoids) abundant. Chondrichthyes or cartilaginous fishes are jawed Fish with paired fins paired nostrils scales two-chambered hearts and skeletons made of Cartilage rather Echinoderms (Phylum Echinodermata) are a phylum of marine Animals (including Sea stars) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the Echinoderms (phylum Echinodermata Blastoids (class Blastoidea are an Extinct type of stemmed Echinoderm. Corals, bryozoa, goniatites and brachiopods (Productida, Spiriferida, etc. Corals are Marine organisms from the class Anthozoa and exist as small Sea anemone –like Polyps typically in colonies of many Bryozoans are tiny colonial Animals that generally build stony Skeletons of Calcium carbonate, superficially similar to Coral (although some Goniatites are an extinct group of ammonoid, which are shelled Cephalopods related to Squids Belemnites Octopuses Spiriferida is an order of extinct articulate Brachiopod, Fossils of which are known for their long hinge-line which is often the widest part of the shell ) very common. But trilobites and nautiloids decline. Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Nautiloids are a group of marine Mollusks in the subclass Nautiloidea, which all possess an external shell the best-known example being the modern Nautiluses Glaciation in East Gondwana. "Glacial" and "Glaciation" redirect here For the geological periods see Glacial period. Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Tuhua Orogeny in New Zealand tapers off. | 326. 4 ± 1. 6* | |||
| Middle | Viséan | 345. The Middle Mississippian is the second of three subepochs of the Mississippian epoch of the Carboniferous period. The Viséan age is the middle of three ages in the Mississippian Subperiod of the Carboniferous Period. 3 ± 2. 1* | |||||
| Lower/Early | Tournaisian | 359. The Early Mississippian (also known as the Lower Mississippian) is the first of three subepochs of the Mississippian epoch of the Carboniferous The Tournasian age is one of the three ages in the Mississippian Epoch of the Carboniferous Period 2 ± 2. 5* | |||||
| Devonian | Upper/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. The Devonian is a geologic period and system of the Paleozoic era spanning from to million years ago. Lycopodiopsida is a class of plants often loosely grouped as the fern allies, and includes the clubmosses Equisetopsida, or Sphenopsida, is a class of Plants with a fossil record going back to the Devonian. A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta A seed (in some plants referred to as a kernel) is a small embryonic Plant enclosed in a covering called the seed coat usually with some stored The progymnosperms are a Clade of woody plants including the Ginkgoales, Gymnosperms Angiosperms and many extinct forms such as Archaeopteris A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or Archaeopteris is an Extinct genus of tree-like plants with Fern -like leaves Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described Strophomenid and atrypid brachiopods, rugose and tabulate corals, and crinoids are all abundant in the oceans. Strophomenida is a large extinct order of Articulate Brachiopods that existed from the lower Ordovician to the lower Jurassic Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also The Rugosa Rose is also sometimes just called "Rugosa" The Rugosa, also called the Tetracoralla, are an extinct order The tabulate corals, forming the order Tabulata, are an Extinct form of Coral. Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the Echinoderms (phylum Echinodermata Goniatite ammonoids are plentiful, while squid-like coleoids arise. Goniatites are an extinct group of ammonoid, which are shelled Cephalopods related to Squids Belemnites Octopuses Ammonites are an extinct group of marine animals of the subclass Ammonoidea in the class Cephalopoda phylum Subclass Coleoidea is the grouping of Cephalopods containing all the primarily soft-bodied creatures Trilobites and armoured agnaths decline, while jawed fishes (placoderms, lobe-finned and ray-finned fish, and early sharks) rule the seas. The Placodermi were a class of armoured Prehistoric fishes known from Fossils which lived from the late Silurian to the end of the Devonian Sarcopterygii (from Greek σαρξ sarx, flesh and πτερυξ pteryx, fin is traditionally the class of lobe-finned Fishes consisting Osteichthyes (ˌɒstiːˈɪkθiːz also called bony fish, are a taxonomic Class of Fish that includes the ray-finned fish ( Actinopterygii Chondrichthyes or cartilaginous fishes are jawed Fish with paired fins paired nostrils scales two-chambered hearts and skeletons made of Cartilage rather First amphibians still aquatic. Tetrapods ( Greek τετραποδη tetrapoda, Latin Quadruped, "four-footed" are Vertebrate Animals "Old Red Continent" of Euramerica. Euramerica (also known as Laurussia or Old Red Continent) was a minor Supercontinent created in the Devonian as the result of a collision between 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. The Acadian orogeny is a middle Paleozoic deformation especially in the northern Appalachians, between New York and Newfoundland. North Africa or Northern Africa is the Northernmost Region of the African Continent, separated by the Sahara from Sub-Saharan The Appalachian Mountains ( often called the Appalachians, are a vast system of mountains in eastern North America. The Antler orogeny is a mountain-building episode that is named for Antler Peak at Battle Mountain Nevada. The Variscan (or Hercynian) orogeny is a geologic mountain-building event caused by Late Paleozoic Continental collision between Laurasia New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island | 374. 5 ± 2. 6* | |||
| Frasnian | 385. 3 ± 2. 6* | ||||||
| Middle | Givetian | 391. 8 ± 2. 7* | |||||
| Eifelian | 397. 5 ± 2. 7* | ||||||
| Lower/Early | Emsian | 407. 0 ± 2. 8* | |||||
| Pragian | 407. 0 ± 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. The Silurian is a geologic period and system that extends from the end of the Ordovician period about 443 Vascular plants (also known as tracheophytes or higher plants) are those Plants that have lignified tissues for conducting Rhyniophyta is a division of early Vascular plants including the class Rhyniopsida. Millipedes (Class Diplopoda, previously also known as Chilognatha are Arthropods that have two pairs of legs per segment (except for the first segment behind Arthropleura was a 03–26 Metre (1–85 feet) long relative of Centipedes and Millipedes native to the Upper First jawed fishes, as well as many armoured jawless fish, populate the seas. Gnathostomata is the group of Vertebrates with Jaws The group is traditionally a superclass, including the familiar classes of Fish, Ostracoderms ("shell-skinned" are any of several groups of extinct, primitive jawless Fishes that were covered in an armor of bony plates Agnatha ( Greek, "no jaws" is a Paraphyletic superclass of jawless fish in the phylum Chordata, subphylum Vertebrata Sea-scorpions reach large size. The eurypterids (sea scorpions include the largest known Arthropod that ever lived (with the possible exception of Arthropleuridae) Tabulate and rugose corals, brachiopods (Pentamerida, Rhynchonellida, etc. The tabulate corals, forming the order Tabulata, are an Extinct form of Coral. The Rugosa Rose is also sometimes just called "Rugosa" The Rugosa, also called the Tetracoralla, are an extinct order Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also The Taxonomic order Rhynchonellida is one of the two main groups of living articulate Brachiopods the other being the order Terebratulida ), and crinoids all abundant. Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the Echinoderms (phylum Echinodermata Trilobites and mollusks diverse; graptolites not as varied. Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Molluscs are animals belonging to the phylum Mollusca. There are around 250000 extant Species within the phylum with an estimated 70000 Graptolites (Graptolithina are Fossil colonial Animals known chiefly from the Upper Cambrian through the Lower Carboniferous ( Mississippian Beginning of Caledonian Orogeny for hills in England, Ireland, Wales, Scotland, and the Scandinavian Mountains. The Caledonian orogeny is a mountain building event recorded in the Mountains and Hills of northern Scotland, Ireland, England, England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. The Scandinavian Mountains in Swedish Skanderna, Fjällen ("the Fells quot or Kölen, and in Norwegian Kjølen, Also continued into Devonian period as the Acadian Orogeny, above. The Acadian orogeny is a middle Paleozoic deformation especially in the northern Appalachians, between New York and Newfoundland. Taconic Orogeny tapers off. The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight Lachlan Orogeny on Australian Continent tapers off. The Lachlan Fold Belt ( LFB) or Lachlan Orogen is a geological subdivision of the east part of Australia. | 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. Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec 0 ± 1. 9* | |||||
| Aeronian | 439. 0 ± 1. 8* | ||||||
| Rhuddanian | 443. 7 ± 1. 5* | ||||||
| Ordovician | Upper/Late | Hirnantian | Invertebrates diversify into many new types (e. The Ordovician is a geologic period and system, the second of six of the Paleozoic era, and covers the time between 488 The Late Ordovician, also called the Upper Ordovician by Geologists is the third epoch of the Ordovician period The Hirnantian is the seventh and final internationally-recognized stage of the Ordovician Period of the Paleozoic Era. An invertebrate is an Animal lacking a Vertebral column. The group includes 98% of all animal Species — all animals except those in the Chordate g. , long straight-shelled cephalopods). An orthocone is a usually long straight shell of a Nautiloid Cephalopod. Orthocerida are an order of extinct Nautiloid Cephalopods that lived from the Early Ordovician (about 500 million years ago to the Late Permian Early corals, articulate brachiopods (Orthida, Strophomenida, etc. Corals are Marine organisms from the class Anthozoa and exist as small Sea anemone –like Polyps typically in colonies of many Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also ), bivalves, nautiloids, trilobites, ostracods, bryozoa, many types of echinoderms (crinoids, cystoids, starfish, etc. Bivalves are Molluscs belonging to the class Bivalvia. They have two-part shells and typically both valves are symmetrical along the hinge line Nautiloids are a group of marine Mollusks in the subclass Nautiloidea, which all possess an external shell the best-known example being the modern Nautiluses Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Ostracoda is a class of the Crustacea, sometimes known as the seed shrimp because of their appearance Bryozoans are tiny colonial Animals that generally build stony Skeletons of Calcium carbonate, superficially similar to Coral (although some Echinoderms (Phylum Echinodermata) are a phylum of marine Animals (including Sea stars) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the Echinoderms (phylum Echinodermata Starfish (also called sea stars) are any Echinoderms belonging to the class Asteroidea. ), branched graptolites, and other taxa all common. Graptolites (Graptolithina are Fossil colonial Animals known chiefly from the Upper Cambrian through the Lower Carboniferous ( Mississippian Conodonts (early planktonic vertebrates) appear. Conodonts are extinct chordates resembling eels classified in the class Conodonta. Plankton consist of any drifting Organisms ( Animals Plants Archaea, or Bacteria) that inhabit the Pelagic zone of Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes First green plants and fungi on land. The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Ice age at end of period. | 445. 6 ± 1. 5* | |||
| other faunal stages | 460. The Ordovician is a geologic period and system, the second of six of the Paleozoic era, and covers the time between 488 9 ± 1. 6* | ||||||
| Middle | Darriwilian | 468. The Middle Ordovician (from 472 to 461 million years ago) is the second subdivision of the Ordovician period The Darriwilian Faunal stage includes most of the Late Llanwirn 1 ± 1. 6* | |||||
| other faunal stages | 471. The Ordovician is a geologic period and system, the second of six of the Paleozoic era, and covers the time between 488 8 ± 1. 6* | ||||||
| Lower/Early | Arenig | 471. The Early Ordovician, also called the Lower Ordovician by Geologists is the first subdivision of the Ordovician period and marked a great diversification In Geology, the Arenig group is the name applied to the lowest stage of the Ordovician System 8 ± 1. 7* | |||||
| Tremadocian | 488. The Tremadocian is the first internationally-recognized stage of the Ordovician Period of the Paleozoic Era. 3 ± 1. 7* | ||||||
| Cambrian | Furongian | other faunal stages | Major diversification of life in the Cambrian Explosion. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with The Furongian (which represented approximately the old notions of Late Cambrian, Merioneth, Croixian, or Potsdamian) is the third and final The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with The Cambrian explosion or Cambrian radiation was the seemingly rapid appearance of most major groups of complex Animals around, as evidenced by the Many fossils; most modern animal phyla appear. A phylum ( Plural: phyla) is a Taxonomic rank between Kingdom and above Class. First chordates appear, along with a number of extinct, problematic phyla. Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Reef-building Archaeocyatha abundant; then vanish. The Archaeocyatha or archaeocyathids ("ancient cups" were Sessile Trilobites, priapulid worms, sponges, inarticulate brachiopods (unhinged lampshells), and many other animals numerous. Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Priapulida ( priapulid worms or penis worms, from Gr πριάπος priāpos ' Priapus ' + Lat The sponges or poriferans (from Latin porus "pore" and ferre "to bear" are Animals Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also Anomalocarids are giant predators, while many Ediacaran fauna die out. Anomalocaridids are a group of very early marine animals known from fossils found in Cambrian deposits in China, USA, Canada, Poland Prokaryotes, protists (e. The prokaryotes (proʊˈkærioʊts singular prokaryote /proʊˈkæriət/ are a group of Organisms that lack a Cell nucleus (= karyon or any other Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this g. , forams), fungi and algae continue to present day. The Foraminifera, ("Hole Bearers" or forams for short are a large group of Amoeboid Protists with reticulating Pseudopods fine A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Gondwana emerges. Gondwana (ɡɒnˈdwɑːnə originally Gondwanaland) was a southern Supercontinent that existed about 500 to 200 Ma ago Petermann Orogeny on the Australian Continent tapers off (550-535 MYA). The Petermann Orogeny was an intra Continental event that affected basement rocks of the northern Musgrave Province and Proterozoic Sediments of Ross Orogeny in Antarctica. Adelaide Geosyncline (Delamerian Orogeny), majority of orogenic activity from 514-500 MYA. The Adelaide Geosyncline (also known as Adelaide Rift Complex) is a major geological province in central South Australia. Lachlan Orogeny on Australian Continent, c. The Lachlan Fold Belt ( LFB) or Lachlan Orogen is a geological subdivision of the east part of Australia. 540-440 MYA. Atmospheric Carbon Dioxide content roughly 20-35 times present-day (Holocene) levels (6000 ppmv compared to today's 385 ppmv)[9]</ref> | 496. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC 0 ± 2. 0* | |||
| Paibian/Ibexian/ Ayusokkanian/Sakian/Aksayan |
501. In the Geologic timescale, the Paibian is the age of the Furongian epoch of the Cambrian period of the Paleozoic The Ibexian is recognized as the youngest Cambrian and oldest Ordovician series in North America The Ayusokkanian is a Russian and Kazakhian faunal stage that occurred during the Early Cambrian period The Sakian is a Russian and Kazakhian faunal stage of the Late Cambrian period that occurred between 494 The Aksayan is a Russian and Kazakhian faunal stage of the Cambrian that occurred between 493 To 491 0 ± 2. 0* | ||||||
| Middle | other faunal stages | 513. The Middle Cambrian (also known as Albertan, Acadian, St David's, or Saint David's) is the second of three geological epochs of the The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with 0 ± 2. 0 | |||||
| Lower/Early | other faunal stages | 542. The Early Cambrian (also known as the Caerfai, Waucoban, or Georgian) is the first of three geological epochs of the Cambrian The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with 0 ± 1. 0* | |||||
| Precam- brian[13] |
Proter- ozoic[14] |
Neo- proterozoic[14] |
Ediacaran | Good fossils of the first multi-celled animals. The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current The Proterozoic (ˌproʊtərəˈzoʊɪk is a geological eon representing a period before the first abundant complex life on Earth. The Neoproterozoic Era is the unit of geologic time from 1000 to 542 +/- 0 The Ediacaran Period (ˌiːdiˈækərən named after the Ediacara Hills of South Australia) is the last geological period of the Neoproterozoic FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Ediacaran biota flourish worldwide in seas. The Ediacara (ˌiːdɪˈækərə formerly Vendian) biota are ancient lifeforms of the Ediacaran Period which represent the earliest known complex Simple trace fossils of possible worm-like Trichophycus, etc. Trace fossils, also called ichnofossils (ˈɪknoʊfɒsɨl ιχνος or ikhnos meaning "trace" or "track" are geological records of biological Trichophycus pedum (or Treptichnus pedum; formerly Phycodes pedum) is regarded as the earliest widespread complex Trace fossil First sponges and trilobitomorphs. The sponges or poriferans (from Latin porus "pore" and ferre "to bear" are Animals Trilobites ("three-lobes" are extinct Arthropods that form the class Trilobita. Enigmatic forms include many soft-jellied creatures shaped like bags, disks, or quilts (like Dickinsonia). Dickinsonia is an iconic fossil of the Ediacaran biota. It (roughly resembles a bilaterally symmetrical ribbed oval Taconic Orogeny in North America. The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight Aravalli Range orogeny in Indian Subcontinent. The Aravalli Range is a range of mountains in western India running approximately 800 km from northeast to southwest across Rajasthan state Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and This article deals with the geophysical region in Asia For geopolitical treatments see South Asia. Beginning of Petermann Orogeny on Australian Continent. The Petermann Orogeny was an intra Continental event that affected basement rocks of the northern Musgrave Province and Proterozoic Sediments of Beardmore Orogeny in Antarctica, 633-620 MYA. | 630 +5/-30* | ||
| Cryogenian | Possible "Snowball Earth" period. The Cryogenian (from Greek cryos "cold" and genesis "birth" is a Geologic period that lasted from. The Snowball Earth Hypothesis as it was originally proposed]] Evidence The Snowball Earth hypothesis was originally devised to explain the apparent presence of Fossils still rare. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Rodinia landmass begins to break up. For the Genus of Metalmark butterflies, see Rodinia (butterfly. Late Ruker / Nimrod Orogeny in Antarctica tapers off. | 850[15] | |||||
| Tonian | Rodinia supercontinent persists. The Tonian (from Greek tonas, "stretch" is the first Geologic period in the Neoproterozoic Era and lasted from For the Genus of Metalmark butterflies, see Rodinia (butterfly. Trace fossils of simple multi-celled eukaryotes. Trace fossils, also called ichnofossils (ˈɪknoʊfɒsɨl ιχνος or ikhnos meaning "trace" or "track" are geological records of biological Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex First radiation of dinoflagellate-like acritarchs. The dinoflagellates are a large group of Flagellate Protists Most are marine Plankton, but Acritarchs are small organic Fossils present from approximately to the present Grenville Orogeny tapers off in North America. The Grenville orogeny was an episode of mountain-building ( Orogeny) associated with the assembly of the ancient Supercontinent Rodinia. Pan-African Orogeny in Africa. Lake Ruker / Nimrod Orogeny in Antarctica, 1000 ± 150 MYA. Edmundian Orogeny (c. 920 - 850 MYA), Gascoyne Complex, Western Australia. The Gascoyne Complex is a Terrane of Proterozoic Granite and Metamorphic rock in the central-western part of Western Australia. Western Australia is a state occupying the entire western third of the Australian continent. Adelaide Geosyncline laid down on Australian Continent, beginning of Adelaide Geosyncline (Delamerian Orogeny) in that continent. The Adelaide Geosyncline (also known as Adelaide Rift Complex) is a major geological province in central South Australia. The Adelaide Geosyncline (also known as Adelaide Rift Complex) is a major geological province in central South Australia. | 1000[15] | |||||
| Meso- proterozoic[14] |
Stenian | Narrow highly metamorphic belts due to orogeny as Rodinia formed. The Mesoproterozoic Era is a geologic era that occurred between 1600 Ma and 1000 Ma (million years ago The Stenian (from Greek stenos, "narrow" is the final Geologic period in the Mesoproterozoic Era and lasted Metamorphic rock is the result of the transformation of an existing rock type the protolith, in a process called Metamorphism, which means "change Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and For the Genus of Metalmark butterflies, see Rodinia (butterfly. Late Ruker / Nimrod Orogeny in Antarctica possibly begins. Musgrave Orogeny (c. 1080 MYA), Musgrave Block, Central Australia. The Musgrave Block is an east-west trending belt of Proterozoic Granulite - Gneiss basement rocks approximately 500km long Central Australia/Alice Springs Region is one of the five regions in the Northern Territory. | 1200[15] | ||||
| Ectasian | Platform covers continue to expand. The Ectasian (from Greek ectasis, "extension" is the second Geologic period in the Mesoproterozoic era and lasted In Geology, a platform cover is the Sedimentary and Volcanic deposits that lie on top of a Craton. Green algae colonies in the seas. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged In Biology, a colony (from Latin colonia) refers to several individual Organisms of the same Species living closely together usually Grenville Orogeny in North America. The Grenville orogeny was an episode of mountain-building ( Orogeny) associated with the assembly of the ancient Supercontinent Rodinia. | 1400[15] | |||||
| Calymmian | Platform covers expand. The Calymmian (from Greek calymma, "cover" is the first Geologic period in the Mesoproterozoic Era and lasted In Geology, a platform cover is the Sedimentary and Volcanic deposits that lie on top of a Craton. Barramundi Orogeny, MacArthur Basin, Northern Australia, and Isan Orogeny, c. 1600 MYA, Mount Isa Block, Queensland | 1600[15] | |||||
| Paleo- proterozoic[14] |
Statherian | First complex single-celled life: protists with nuclei. The term northern Australia is generally considered to include the States and territories of Australia of Queensland and the Northern Territory. Circa (often abbreviated c, ca, ca or cca and sometimes Italicized to show it is Latin) means "about" The Paleoproterozoic (ˌpeɪlɪoʊˌproʊtərəˈzoʊɪk also spelled Palaeoproterozoic) is the first of the three sub-divisions ( eras) of the The Statherian (stəˈθɪəriən statheros, meaning "stable firm" is the final Geologic period in the Paleoproterozoic Era Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this Columbia is the primordial supercontinent. Columbia is the name of one of the Earth's oldest Supercontinents It was first proposed by J Kimban Orogeny in Australian Continent ends. Yapungku Orogeny on North Yilgarn craton, in Western Australia. Western Australia is a state occupying the entire western third of the Australian continent. Mangaroon Orogeny, 1680-1620 MYA, on the Gascoyne Complex in Western Australia. The Gascoyne Complex is a Terrane of Proterozoic Granite and Metamorphic rock in the central-western part of Western Australia. Western Australia is a state occupying the entire western third of the Australian continent. Kararan Orogeny (1650- MYA), Gawler Craton, South Australia. South Australia is a state of Australia in the southern central part of the country | 1800[15] | ||||
| Orosirian | The atmosphere became oxygenic. The Orosirian (ˌɒroʊˈsɪəriən oroseira - ὀροσειρά, meaning "mountain range" is the third Geologic period in the Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Vredefort and Sudbury Basin asteroid impacts. Vredefort crater is the largest verified Impact crater on Earth. The Sudbury Basin, also known as Sudbury Structure or the Sudbury Nickel Irruptive, is the second largest known Impact crater or Astrobleme Much orogeny. Orogeny (Greek for "mountain generating" is the process of natural Mountain building and may be studied as a tectonic structural event as a geographical event and Penokean and Trans-Hudsonian Orogenies in North America. The Trans-Hudson orogeny, Trans-Hudsonian orogeny, Trans-Hudson orogen (THO or Trans-Hudson Orogen Transect (THOT (also referred to as Early Ruker Orogeny in Antarctica, 2000 - 1700 MYA. Glenburgh Orogeny, Glenburgh Terrane, Australian Continent c. 2005 - 1920 MYA. Circa (often abbreviated c, ca, ca or cca and sometimes Italicized to show it is Latin) means "about" Kimban Orogeny, Gawler craton in Australian Continent begins. The Gawler Craton covers approximately 440000 square kilometres of central South Australia | 2050[15] | |||||
| Rhyacian | Bushveld Formation formed. The Rhyacian (raɪˈeɪsiən Ρυαξ ( rhyax) meaning "stream of Lava " is the second Geologic period in the Paleoproterozoic The Bushveld is a tropical savanna Ecoregion of Southern Africa that encompasses most of Limpopo Province and part of the North West Province Huronian glaciation. The Huronian Glaciation extended from 2400 mya to 2100 mya during the Siderian and Rhyacian periods of the Paleoproterozoic era | 2300[15] | |||||
| Siderian | Oxygen Catastrophe: banded iron formations formed. The Siderian (saɪˈdɪəriən sideros meaning "iron" is the first Geologic period in the Paleoproterozoic Era and lasted from 2500 The Oxygen Catastrophe was a massive environmental change believed to have happened during the Siderian period at the beginning of the Paleoproterozoic Banded iron formations (also known as banded ironstone formations or BIF s are a distinctive type of rock often found in primordial ( Precambrian) Sedimentary Sleaford Orogeny on Australian Continent, Gawler Craton 2440-2420 MYA. The Gawler Craton covers approximately 440000 square kilometres of central South Australia | 2500[15] | |||||
| Archean[14] | Neoarchean[14] | Stabilization of most modern cratons; possible mantle overturn event. The Neoarchean (ˌniːoʊɑrˈkiːən also spelled Neoarchaean) is a geologic era within the Archaean. A craton ( Greek kratos / κρἀτος ( neut. "strength" is an old and stable part of the Continental crust that has survived The mantle is a part of an Astronomical object. The interior of the Earth, similar to the other Terrestrial planets, is Chemically divided Insell Orogeny, 2650 ± 150 MYA. Abitibi greenstone belt in present-day Ontario and Quebec begins to form, stablizes by 2600 MYA. The Abitibi greenstone belt is a 2800-2600 million year old Greenstone belt that spans across the Ontario - Quebec border in Canada. Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec Quebec (kwɨˈbɛk | 2800[15] | ||||
| Mesoarchean[14] | First stromatolites (probably colonial cyanobacteria). The Mesoarchean (ˌmiːzoʊɑrˈkiːən also spelled Mesoarchaean) is a geologic era within the Archean, spanning 3200 Ma to 2800 Stromatolites (from Greek στρώμα strōma, mattress bed stratum and λιθος lithos, rock are layered accretionary Structures formed in In Biology, a colony (from Latin colonia) refers to several individual Organisms of the same Species living closely together usually Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy Oldest macrofossils. Macrofossils (occasionally spelled " macro-fossil " are preserved organic remains large enough to be visible without a Microscope. Humboldt Orogeny in Antarctica. Blake River Megacaldera Complex begins to form in present-day Ontario and Quebec, ends by roughly 2696 MYA. The Blake River Megacaldera Complex, also called the Blake River Group, is a giant subaqueous Caldera cluster or a nested caldera system that spans across the Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec Quebec (kwɨˈbɛk | 3200[15] | |||||
| Paleoarchean[14] | First known oxygen-producing bacteria. The Paleoarchean (ˌpeɪlɪoʊɑrˈkiːən also spelled Palaeoarchaean) is a geologic era within the Archaean. Photoautotrophs or Phototroph ( Gk: photo = light auto = self troph = nourishment are Organisms (commonly plants that carry out Photosynthesis The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Oldest definitive microfossils. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Oldest cratons on earth (such as the Canadian Shield and the Pilbara Craton) may have formed during this period[16]. A craton ( Greek kratos / κρἀτος ( neut. "strength" is an old and stable part of the Continental crust that has survived The Canadian Shield &mdash also called the Laurentian Plateau, or Bouclier Canadien (French &mdash is a large geological shield covered by The Pilbara craton (the Pilbara province in northwest Western Australia) along with the Kaapvaal craton (the Kaapvaal province of South Africa Rayner Orogeny in Antarctica. | 3600[15] | |||||
| Eoarchean[14] | Simple single-celled life (probably bacteria and perhaps archaea). In the Geologic record the Eoarchean Erathem (ˌiːoʊɑrˈkiːən also spelled Eoarchaean) and the Eoarchean era in the Geologic The prokaryotes (proʊˈkærioʊts singular prokaryote /proʊˈkæriət/ are a group of Organisms that lack a Cell nucleus (= karyon or any other The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Oldest probable microfossils. Micropaleontology (also sometimes spelled as micropalaeontology) is that branch of Paleontology which studies microfossils | 3800 | |||||
| Hadean [14][17] |
Lower Imbrian[14][18] | This era overlaps the end of the Late Heavy Bombardment of the inner solar system. The Hadean (ˈheɪdiən is the geologic eon before the Archean. In the Lunar geologic timescale, the Lower Imbrian epoch occurred between 3850 million years ago to about 3800 million years ago The Late Heavy Bombardment (commonly referred to as the lunar cataclysm, or LHB) is a period of time approximately 3800 to 4100 million years ago ( mya The Solar System consists of the Sun and those celestial objects bound to it by Gravity. The Solar System consists of the Sun and those celestial objects bound to it by Gravity. | c. 3850 | ||||
| Nectarian[14][18] | This era gets its name from the lunar geologic timescale when the Nectaris Basin and other major lunar basins were formed by large impact events. The Nectarian Period of the Lunar geologic timescale runs from 3920 million years ago to 3850 million years ago The lunar geologic timescale (or selenologic timescale) divides the history of Earth 's moon into five generally recognized geologic periods the Copernican The Sea of Nectar ( Mare Nectaris) is a small Lunar mare or sea (a volcanic lava plain noticeably darker than the rest of the Moon 's surface located See also Impact crater An impact event is the Collision of a large Meteoroid, Asteroid or Comet (generically | c. 3920 | |||||
| Basin Groups[14][18] | Oldest known rock (4030 Ma)[19]. Basin Groups refers to 9 informal subdivisions of the lunar Pre-Nectarian geologic period. The first Lifeforms and self-replicating RNA molecules may have evolved on earth around 4000 Ma during this era. See also Biological reproduction Self-replication is any process by which a thing might make a copy of itself Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by Naiper Orogeny in Antarctica, 4000 ± 200 MYA. | c. 4150 | |||||
| Cryptic[14][18] | Oldest known mineral (Zircon, 4406±8 Ma[20]). The Cryptic era is an informal term that refers to the earliest geologic evolution of the Earth and Moon. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is Annum is one form of the Latin noun meaning Year, not a form normally used for derivatives in modern languages the accusative singular Formation of Earth (4567. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 17 to 4570 Ma) | c. 4570 | |||||
- ^ John McPhee, Basin and Range, New York:Farrar, Straus and Giroux, 1981, pp. 95-100.
- ^ John McPhee, Basin and Range, pp. 113-114.
- ^ (1974) Great Soviet Encyclopedia, 3rd ed. The Great Soviet Encyclopedia ( Большая Советская Энциклопедия, or БСЭ; transliterated Bolshaya Sovetskaya Entsiklopediya (in Russian), Moscow: Sovetskaya Enciklopediya, vol. 16, p. 50.
- ^ Felix M. Gradstein, James G. Ogg, Alan G. Smith (Editors); A Geologic Time Scale 2004, Cambridge University Press, 2005, (ISBN 0-521-78673-8)
- ^ Cox & Richard, A formal model for the geologic time scale and global stratotype section and point, compatible with geospatial information transfer standards, Geosphere, volume 1, pp 119-137, Geological Society of America, 2005
- ^ Paleontologists often refer to faunal stages rather than geologic (geological) periods. The stage nomenclature is quite complex. See The Paleobiology Database. Retrieved on 2006-03-19. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1279 - A Mongolian victory in the Battle of Yamen ends the Song Dynasty in China. for an excellent time ordered list of faunal stages.
- ^ a b 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. Radiometric dating (often called radioactive dating) is a technique used to date materials usually based on a comparison between the observed abundance of a naturally occurring The dates and errors quoted above are according to the International Commission on Stratigraphy 2004 time scale. The International Commission on Stratigraphy (ICS, sometimes referred to by the unofficial " International Stratigraphic Commission " is a daughter or major Subcommittee Dates labeled with a * indicate boundaries where a Global Boundary Stratotype Section and Point has been internationally agreed upon: see List of Global Boundary Stratotype Sections and Points for a complete list. A Global Boundary Stratotype Section and Point, abbreviated GSSP, is an internationally agreed upon stratigraphic section which serves as the reference section for This is a list of Global Boundary Stratotype Sections and Points.
- ^ a b c d Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. The Cenozoic (also Caenozoic or Cainozoic) Era (ˌsiːnəˈzoʊɪk/ /ˌsɛn- (meaning "new life" ( Greek ( kainos) "new" Overview The term Quaternary ("fourth" was proposed by Giovanni Arduino in 1759 for alluvial deposits in the Po river valley in northern The chuprichondira geological time interval covers roughly the time span between the demise of the non- avian Dinosaurs and beginning of the most recent Ice Age, approximately The Neogene is a geologic period and system starting 2303 ± 0 The Paleogene (alternatively Palaeogene) is a geologic period and system that began 65 However, the International Commission on Stratigraphy has recently decided to stop endorsing the terms Quaternary and Tertiary as part of the formal nomenclature.
- ^ a b c d e f For more information on this, see the following articles: Earth's atmosphere, Carbon Dioxide, Carbon dioxide in the Earth's atmosphere, Image:Phanerozoic_Carbon_Dioxide.png, Image:65 Myr Climate Change.png, Image:Five Myr Climate Change.png, and Template:DF temperature
- ^ The start time for the Holocene epoch is here given as 11,430 years ago ± 130 years (that is, between 9610 BC-9560 BC and 9350 BC-9300 BC). Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Carbon dioxide forms approximately 004% of the Earth's atmosphere. The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe Africa Before Present (BP years are a time scale used in Archaeology, Geology, and other scientific disciplines to specify when events in the past occurred For further discussion of the dating of this epoch, see Holocene. The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC
- ^ a b MYA = Million Years Ago
- ^ a b In North America, the Carboniferous is subdivided into Mississippian and Pennsylvanian Periods. The Pennsylvanian is a subperiod of the Carboniferous period lasting from roughly to Ma (million years ago
- ^ The Precambrian is also known as Cryptozoic. The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current
- ^ a b c d e f g h i j k l m n The Proterozoic, Archean and Hadean are often collectively referred to as the Precambrian Time or sometimes, also the Cryptozoic. The Proterozoic (ˌproʊtərəˈzoʊɪk is a geological eon representing a period before the first abundant complex life on Earth. The Hadean (ˈheɪdiən is the geologic eon before the Archean. The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current
- ^ a b c d e f g h i j k l Defined by absolute age (Global Standard Stratigraphic Age). In the Stratigraphy sub-discipline of Geology, a Global Standard Stratigraphic Age, officially abbreviated GSSA, is a chronological reference point and
- ^ The age of the oldest measurable craton, or continental crust, is dated to 3600-3800 Ma
- ^ Though commonly used, the Hadean is not a formal eon and no lower bound for the Archean and Eoarchean have been agreed upon. A craton ( Greek kratos / κρἀτος ( neut. "strength" is an old and stable part of the Continental crust that has survived The continental crust is the layer of granitic, Sedimentary, and Metamorphic rocks which form the Continents and the areas of shallow seabed The Hadean (ˈheɪdiən is the geologic eon before the Archean. The Hadean has also sometimes been called the Priscoan or the Azoic. Sometimes, the Hadean can be found to be subdivided according to the lunar geologic time scale. The lunar geologic timescale (or selenologic timescale) divides the history of Earth 's moon into five generally recognized geologic periods the Copernican These eras include the Cryptic and Basin Groups (which are subdivisions of the pre-Nectarian era), Nectarian, and Lower Imbrian eras. The Cryptic era is an informal term that refers to the earliest geologic evolution of the Earth and Moon. Basin Groups refers to 9 informal subdivisions of the lunar Pre-Nectarian geologic period. The Pre-Nectarian Period of the Lunar geologic timescale runs from 4533 million years ago (the time of the initial formation of the Moon) to 3920 million years ago The Nectarian Period of the Lunar geologic timescale runs from 3920 million years ago to 3850 million years ago In the Lunar geologic timescale, the Lower Imbrian epoch occurred between 3850 million years ago to about 3800 million years ago
- ^ a b c d These era names were taken from the Lunar geologic timescale. The lunar geologic timescale (or selenologic timescale) divides the history of Earth 's moon into five generally recognized geologic periods the Copernican Their use for Earth geology is unofficial.
- ^ Oldest rock on earth is the Acasta Gneiss, and it dates to 4. The Acasta Gneiss is a rock Outcrop of Archaean Tonalite Gneiss in the Slave craton in Northwest Territories 03 Ga, located in the Northwest Territories of Canada. The Northwest Territories (ˌnɔrθˌwɛstˈtɛrɨtɔriz ( NWT or NT; French, les Territoires du Nord-Ouest) is a territory Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page
- ^ http://www.geology.wisc.edu/%7Evalley/zircons/Wilde2001Nature.pdf
References and footnotes
See also
- Age of the Earth
- Anthropocene
- Cosmological timeline
- Deep time
- Geological history of Earth
- History of Earth
- List of fossil sites (with link directory)
- Logarithmic timeline
- Lunar geologic timescale
- Martian geologic timescale
- Natural history
- Timeline of evolution
- Timeline of human evolution
- Time line of the geologic history of the United States
- Timetable of the Precambrian
External links
- NASA: Geologic Time
- GSA: Geologic Time Scale
- British Geological Survey: Geological Timechart
- GeoWhen Database
- International Commission on Stratigraphy Time Scale
- CHRONOS
- National Museum of Natural History - Geologic Time
- SeeGrid: Geological Time Systems Information model for the geologic time scale
- Exploring Time from Planck Time to the lifespan of the universe
Modern geologists and Geophysicists consider the age of Earth to be around 4 The term Anthropocene is used by some scientists to describe the most recent period in the Earth 's history This timeline of the Big Bang describes the events according to the Scientific theory of the Big Bang, using the cosmological time parameter of Comoving coordinates Deep time is the concept of geologic time first recognized in the 11th century by the Persian geologist and Polymath, Avicenna (Ibn Sina 973-1037 geological history of Earth began 4567 billion years ago when the planets of the Solar System were formed out of the Solar nebula, a disk-shaped mass of The history of Earth covers approximately 46 billion years (4567000000 years from Earth ’s formation out of the Solar nebula to the present This is a worldwide list of important and/or well-known localities where Fossils have been found A logarithmic timeline is a Timeline laid out according to a Logarithmic scale. The lunar geologic timescale (or selenologic timescale) divides the history of Earth 's moon into five generally recognized geologic periods the Copernican The geology of Mars, also known as areology (from Greek grc Ἂρης Arēs, " Ares " and grc -λογία -logia Natural history is the Scientific research of Plants or Animals leaning more towards the Observational than Experimental methods This timeline of the evolution of life outlines the major events in the development The timeline of human evolution outlines the major events in the development of Human Species, and the Evolution of humans' Ancestors It includes This is a timeline of geological and relevant astronomical events on Earth before the Cambrian period started
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