• Thumbnail for Ordovician
    The Ordovician (/ɔːrdəˈvɪʃi.ən, -doʊ-, -ˈvɪʃən/ or-də-VISH-ee-ən, -⁠doh-, -⁠VISH-ən) is a geologic period and system, the second of six periods of the...
    69 KB (7,298 words) - 05:51, 18 March 2024
  • Thumbnail for Late Ordovician mass extinction
    Cap Late D O–S The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is...
    99 KB (10,812 words) - 00:21, 13 April 2024
  • The Late Ordovician, also called the Upper Ordovician by geologists, is the third epoch of the Ordovician period. At this time Western and Central Europe...
    3 KB (267 words) - 16:17, 2 January 2024
  • Thumbnail for Cambrian–Ordovician extinction event
    K–Pg Tr–J P–Tr Cap Late D O–S The Cambrian–Ordovician extinction event, also known as the Cambrian-Ordovician boundary event, was an extinction event that...
    7 KB (792 words) - 07:29, 13 February 2024
  • Thumbnail for Trilobite
    appearing in the Ordovician include: Cyclopyge (Early to Late Ordovician) Selenopeltis (Early to Late Ordovician) Parabolina (Early Ordovician) Cheirurus (Middle...
    110 KB (11,754 words) - 17:47, 15 April 2024
  • Thumbnail for Silurian
    geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago (Mya), to the beginning of the Devonian...
    57 KB (5,666 words) - 09:06, 22 April 2024
  • The Great Ordovician Biodiversification Event (GOBE), was an evolutionary radiation of animal life throughout the Ordovician period, 40 million years after...
    34 KB (3,551 words) - 05:15, 17 February 2024
  • Thumbnail for Sacabambaspis
    Sacabambaspis (category Ordovician jawless fish)
    Sacabambaspis is an extinct genus of jawless fish that lived in the Ordovician period. Sacabambaspis lived in shallow waters on the continental margins...
    9 KB (907 words) - 07:32, 25 April 2024
  • subdivided into six geologic periods (from oldest to youngest): Cambrian Ordovician Silurian Devonian Carboniferous Permian Some geological timescales divide...
    35 KB (3,683 words) - 08:53, 7 April 2024
  • Ice Age (EPIA), the Early Paleozoic Icehouse, the Late Ordovician glaciation, the end-Ordovician glaciation, or the Hirnantian glaciation, occurred during...
    60 KB (6,565 words) - 11:30, 5 January 2024
  • Thumbnail for Cambrian
    Ediacaran period 538.8 million years ago (mya) to the beginning of the Ordovician period 485.4 mya. Its subdivisions, and its base, are somewhat in flux...
    56 KB (5,536 words) - 12:31, 6 April 2024
  • Thumbnail for Ordovician meteor event
    The Ordovician meteor event was a dramatic increase in the rate at which L chondrite meteorites fell to Earth during the Middle Ordovician period, about...
    7 KB (529 words) - 18:45, 23 August 2023
  • the Mexican amber by García-Villafuerte (2018). Redescription of the Ordovician malacostracan Wuningia multisegmenlata is published by Lin (2018). A member...
    175 KB (9,235 words) - 08:52, 7 March 2024
  • Thumbnail for Gastropoda
    [citation needed] As such, it's not until the Ordovician that the first crown-group members arise. By the Ordovician period the gastropods were a varied group...
    48 KB (5,023 words) - 03:16, 7 April 2024
  • into the super-continent Gondwana. The Ordovician spans from 485 million to 444 million years ago. The Ordovician was a time in Earth's history in which...
    59 KB (6,061 words) - 10:45, 19 April 2024
  • Thumbnail for Ireland
    and extending southwest to Longford and south to Navan is a province of Ordovician and Silurian rocks, with similarities to the Southern Uplands province...
    210 KB (21,074 words) - 07:45, 26 April 2024
  • Thumbnail for Knox Supergroup
    Knox Supergroup (category Ordovician geology of Pennsylvania)
    Southeastern United States. The age is from the Late Cambrian to the Early Ordovician. Predominantly, it is composed of carbonates, chiefly dolomite, with some...
    15 KB (1,220 words) - 05:59, 31 March 2024
  • Thumbnail for India
    ; Owen, A. W. (2002), Palaeobiogeography and Biodiversity Change: The Ordovician and Mesozoic–Cenozoic Radiations, Geological Society Special Publication...
    305 KB (26,949 words) - 15:41, 26 April 2024
  • Thumbnail for Cephalopod
    malacology known as teuthology. Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two...
    133 KB (14,920 words) - 18:15, 21 April 2024
  • Thumbnail for Nautiloid
    coast Ordovician genus, in prior times it was employed as a general name given to all straight-shelled nautiloids that lived from the Ordovician to the...
    37 KB (3,449 words) - 06:02, 25 April 2024
  • Thumbnail for Tremadocian
    Tremadocian (category Early Ordovician)
    Tremadocian is the lowest stage of Ordovician. Together with the later Floian Stage it forms the Lower Ordovician Epoch. The Tremadocian lasted from 485...
    16 KB (1,413 words) - 14:25, 20 April 2024
  • Thumbnail for Fossil
    short range in the Middle Ordovician period. If rocks of unknown age have traces of E. pseudoplanus, they have a mid-Ordovician age. Such index fossils...
    104 KB (10,815 words) - 18:58, 26 April 2024
  • Thumbnail for Extinction event
    the Proterozoic Eon. Ordovician–Silurian extinction events (End Ordovician or O–S): 445–444 Ma, just prior to and at the Ordovician–Silurian transition...
    143 KB (15,457 words) - 17:41, 22 April 2024
  • Thumbnail for Acritarch
    (Ordovician) Chlamydosphaeridia (Ordovician) Comasphaeridium (Ordovician) Coronitesta (Ordovician) Coryphidium (Ordovician) Costatilobus (Ordovician)...
    18 KB (1,695 words) - 01:01, 17 April 2024
  • Thumbnail for Geological history of Earth
    Iapetus Ocean and Khanty Ocean. The Ordovician period started at a major extinction event called the Cambrian–Ordovician extinction event some time about...
    49 KB (5,878 words) - 19:24, 28 February 2024
  • Thumbnail for Spore
    protozoa. They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. Bacterial spores are not...
    24 KB (2,055 words) - 22:22, 20 April 2024
  • Thumbnail for Paleontology
    in the Middle Ordovician period. If rocks of unknown age are found to have traces of E. pseudoplanus, they must have a mid-Ordovician age. Such index...
    102 KB (10,169 words) - 22:29, 9 April 2024
  • Cameroceras (category Ordovician cephalopods of North America)
    endocerid cephalopod which lived in equatorial oceans during the entire Ordovician period. Like other endocerids, it was an orthocone, meaning that its shell...
    21 KB (1,574 words) - 23:04, 21 April 2024
  • Thumbnail for Fezouata Formation
    Fezouata Formation (category Ordovician System of Africa)
    Fezouata Shale is a geological formation in Morocco which dates to the Early Ordovician. It was deposited in a marine environment, and is known for its exceptionally...
    88 KB (4,480 words) - 07:47, 24 April 2024
  • an extinct order of stromatoporoid sponges. They lived from the Early Ordovician (Floian stage) to the Late Devonian (Famennian stage), though a few putative...
    18 KB (1,695 words) - 16:06, 31 January 2024