Oligoceno

Sistema/Período Série/Época Andar/Estágio Idade (Ma)
Neogeno Mioceno Aquitaniano mais recente
Paleogeno Oligoceno Chattiano 23.03–28.1
Rupeliano 28.1–33.9
Eoceno Priaboniano 33.9–37.8
Bartoniano 37.8–41.2
Luteciano 41.2–47.8
Ipresiano 47.8–56.0
Paleoceno Tanetiano 56.0–59.2
Selandiano 59.2–61.6
Daniano 61.6–66.0
Cretáceo Superior Maastrichtiano mais antigo
Subdivisão do Paleogeno de acordo com a Tabela Cronoestratigráfica Internacional versão 2015/1 da Comissão Internacional sobre Estratigrafia.

Oligoceno ou oligocénico é a terceira época da era Cenozoica, está compreendida entre há cerca de 36 milhões de anos a cerca de 23 milhões de anos. O nome Oligoceno vem do grego oligos (pouco) e kainos (novo), em referência aos poucos novos mamíferos que surgiram nesta época em comparação com o Eoceno.[1] Divide-se nas idades Rupeliana e Chattiana, da mais antiga para a mais recente.

Clima

Em resumo, o Oligoceno pode ser considerado como um período de transição entre o primitivo mundo tropical de seu antecessor Eoceno e o mundo relativamente moderno de seu sucessor Mioceno.[2]

A principal mudança na geografia do mundo no Oligoceno foi a separação da América do Sul da Antártida, abrindo a passagem de Drake e completando o isolamento da Antártida; este isolamento permitiu a criação da Corrente Circumpolar Antártica, a qual impedia que as correntes oceânicas quentes se aproximassem do continente austral, fazendo sua temperatura diminuir e aumentar sua glaciação. Essa diminuição de temperatura se refletiu em todo o globo, porém de forma muito mais suave que no Eoceno. O aumento da calota polar Antártida também fez com que os níveis dos oceanos no Oligoceno baixassem.

O clima mais frio, também tornou a terra mais secas, fazendo as florestas diminuírem, dando lugar a áreas abertas e prados arborizados, sendo que começara a surgir em torno dos polos vegetações característica de tundra e taiga. Ainda assim, regiões desérticas e semidesérticas eram raras.

Fauna

A fauna do Oligoceno foi, praticamente, uma consequência da Grande Coupure, a extinção no final do Eoceno que tirou da Terra a maioria dos mamíferos primitivos, dentre eles os dinocerados e os brontotérios, o que deu oportunidade para os ancestrais dos atuais mamíferos herbívoros se desenvolverem. Os primeiros a se destacarem nesta época foram os perissodáctilos, tais como os cavalos (Hippomorpha) e os rinocerontes (Ceratomorpha), sendo que alguns deles atingiram grande porte (merecendo destaque o Indricotherium, um Cetaromorpha que é considerado o maior mamífero terrestre que já existiu). Porém também houve um considerável desenvolvimento dos artiodáctilos (bovinos, cervos e porcos) e proboscídeos (elefantes), além de alguns poucos membros de ordens hoje extintas.

Entre os predadores, os creodontes ainda eram os dominantes, porém os carnívoros já estavam se desenvolvendo bastante (alguns especialistas acreditam que este desenvolvimento foi a principal causa da extinção dos creodontes, os quais não conseguiram competir com os carnívoros modernos), merecendo destaque para as famílias dos cães-ursos (Amphicyonidae), os primeiros felinos verdadeiros (Felidae) e os chamados "falsos-dentes-de-sabre" (Nimravidae), que se assemelhavam aos felinos porém tinham pernas mais curtas e são considerados mais primitivos.

Precedido por
Eoceno		 Oligoceno
há 36 – 23
milhões de anos		 Sucedido por
Mioceno

Ver também

Referências

  1. ↑ Atlas Virtual da Pré-História. «Oligoceno». Consultado em 6 de maio de 2018 
  2. ↑ Fenero, Raquel; Thomas, Ellen; Alegret, Laia; Molina, Eustoquio (2010). Evolución paleoambiental del tránsito Eoceno-Oligoceno en el Atlántico sur (Sondeo 1263) basada en foraminíferos bentónicos (em espanhol). Zaragoza: Geogaceta. 4 páginas. ISSN 2173-6545 

Read other articles:

Daftar musim Formula Satu

Formula Satu Musim berjalan Formula Satu musim 2023 Artikel terkait Sejarah Formula Satu Balapan Formula Satu Regulasi Formula Satu Mobil Formula Satu Mesin Formula Satu Ban Formula Satu Daftar Pembalap (Pemenang GPPembalap polePembalap lap tercepat JuaraNomor) Konstruktor (Pemenang GPJuara) Pabrikan mesin (Pemenang GP) MusimGrand PrixSirkuit Pemenang Trofi Promoter Balapan Sistem poin Warna nasionalLivery sponsor Bendera balapanBalapan dengan bendera merah Pembalap wanitaPenyiar TV KematianP...

 

Universitas Montpellier

Koordinat: 43°35′55″N 3°53′32″E / 43.598593°N 3.8921739°E / 43.598593; 3.8921739 Universitas MontpellierUniversité de MontpellierFakultas Kedokteran Universitas Montpellier merupakan fakultas kedokteran tertua yang masing berlangsungLatin: Universitas Montempestellariumcode: la is deprecated JenisNegeriDidirikan1220; 803 tahun lalu (1220)PresidenPhilippe AugéStaf akademik1.900[1]Jumlah mahasiswa41.000[1]Doktor1.700[1]LokasiMon...

 

Concours général

L'expression « concours général » est également utilisée en gymnastique artistique pour désigner un concours prenant en compte l'ensemble des agrès. Concours général Médaille du concours de thème grec (1862). Prix remis Pour chaque discipline : 3 prix 5 accessits 10 mentions Description Concours d'excellence pour lycéens et apprentis Organisateur Université de Paris puis Ministère de l'Éducation nationale Pays France Date de création 1747 modifier  Depuis...

John T. Hunt

American politician John T. HuntSt. Louis Post-Dispatch, November 5, 1902Member of the U.S. House of Representativesfrom Missouri's 11th districtIn officeMarch 4, 1903 – March 3, 1907Preceded byCharles Frederick JoySucceeded byHenry S. Caulfield Personal detailsBornJohn Thomas Hunt(1860-02-02)February 2, 1860St. Louis, Missouri, U.S.DiedNovember 30, 1916(1916-11-30) (aged 56)St. Louis, Missouri, U.S.Resting placeCalvary CemeteryPolitical partyRepublican John Thomas...

 

X Koto Diatas, Solok

X Koto DiatasKecamatanBalerong Sari di Nagari Sulik Aia, X Koto DiatasNegara IndonesiaProvinsiSumatera BaratKabupatenSolokPemerintahan • Camat-Populasi • Total- jiwaKode Kemendagri13.02.12 Kode BPS1303120 Luas- km²Nagari/kelurahan-9 Nagari X Koto Diatas adalah sebuah Kecamatan di Kabupaten Solok, Sumatera Barat, Indonesia. Kecamatan ini berjarak sekitar 43 kilometer berkendara dari ibukota kabupaten Solok ke arah utara melalui Kota Solok. Pusat pemerintahannya be...

 

Sembawang

SembawangInggrisSembawangTionghoa三巴旺Total area7.08 km²Populasi58,700Unit hunian17,874Partai pemerintahPartai Aksi Rakyat[1] Garis perbatasan Konstituensi Perwakilan Kelompok Sembawang Sembawang pada pagi hari Sembawang (Hanzi: 三巴旺) adalah sebuah wilayah yang berada di bagian paling utara Singapura. Anggota Parlemen petahana untuk Konstituensi Sembawang adalah Khaw Boon Wan. Wilayah tersebut merupakan titik paling terdekat dengan Malaysia. Wilayah Sembawang Road End be...

Everette B. Howard

American politician Everette Burgess HowardMember of the U.S. House of Representativesfrom Oklahoma's 1st districtIn officeMarch 4, 1919 – March 3, 1921Preceded byThomas Alberter ChandlerSucceeded byThomas Alberter ChandlerIn officeMarch 4, 1923 – March 3, 1925Preceded byThomas Alberter ChandlerSucceeded bySamuel J. MontgomeryIn officeMarch 4, 1927 – March 3, 1929Preceded bySamuel J. MontgomerySucceeded byCharles O'Connor Personal detailsBornSeptem...

 

Vale (album)

2018 studio album by Black Veil BridesValeStudio album by Black Veil BridesReleasedJanuary 12, 2018Recorded2016–2017StudioFoxy Studios, Los Angeles, CaliforniaGenre Hard rock heavy metal glam metal Length46:37Label Lava Republic Producer John Feldmann Jake Pitts Black Veil Brides chronology Black Veil Brides(2014) Vale(2018) Re-Stitch These Wounds(2020) Singles from Vale The OutsiderReleased: December 21, 2016[1] My VowReleased: September 28, 2017 When They Call My NameRelea...

 

Medora site

Archaeological site in West Baton Rouge Parish, Louisiana, United States Medora site16 WBR 1Diagram of the Medora siteLocation within Louisiana todayLocationPlaquemine, Louisiana, West Baton Rouge Parish, Louisiana, United StatesRegionWest Baton Rouge Parish, LouisianaCoordinates30°19′36.34″N 91°12′5.65″W / 30.3267611°N 91.2015694°W / 30.3267611; -91.2015694HistoryFounded1300 CECulturesPlaquemine cultureSite notesExcavation dates1939-1940Arch...

List of common misconceptions

This is a dynamic list and may never be able to satisfy particular standards for completeness. You can help by adding missing items with reliable sources. Each entry on this list of common misconceptions is worded as a correction; the misconceptions themselves are implied rather than stated. These entries are concise summaries of the main subject articles, which can be consulted for more detail. A common misconception is a viewpoint or factoid that is often accepted as true but which is actu...

 

Georgie Henley

Georgie HenleyHenley pada saat premiere The Chronicles of Narnia: Prince Caspian di InggrisLahirGeorgina Laura Henley/Georgina Helen HenleyNama lainGeorgiePenghargaanPhoenix Film Critics Society Award for Best Performance by a Youth in a Lead or Supporting Role — Female2006 The Chronicles of Narnia: The Lion, the Witch and the WardrobeYoung Artist Award for Best Performance in a Feature Film — Young Actress Age Ten or Younger2006 The Chronicles of Narnia: the Lion, the Witch and the...

 

Liwa al-Umma

Liwa al-Umma Idéologie Islamisme sunnite Objectifs Renversement du régime de Bachar el-Assad Fondation Date de formation 2011 Pays d'origine Syrie Actions Zone d'opération Gouvernorats de Hama, Homs, Idleb et Alep Organisation Chefs principaux Mahdi al-Harati (en 2012) Membres 6 000 (revendiqués en 2012)[1] Fait partie de Armée syrienne libre (2012-2014)Alliance Muhajirin wa-Ansar (depuis 2014) Guerre civile syrienne modifier  Le Liwa al-Umma (arabe : لواء الامة,...

Nothing Left to Lose (song)

This article is about the Mat Kearney song. For other songs, see Nothing Left to Lose. 2006 single by Mat KearneyNothing Left to LoseSingle by Mat Kearneyfrom the album Nothing Left to Lose ReleasedMay 2006Recorded2006GenrePop rock, soft rockLength4:24 (Album Version)3:55 (Radio Edit)LabelColumbiaSongwriter(s)Mat KearneyProducer(s)Robert MarvinMat KearneyMat Kearney singles chronology Nothing Left to Lose (2006) Undeniable (2007) Nothing Left to Lose is a song by American artist Mat Kearney. ...

 

2014 Liverpool City Council election

2014 Liverpool City Council election ← 2012 22 May 2014 (2014-05-22) 2015 → 30 of 90 seats (One Thirdto Liverpool City Council46 seats needed for a majorityTurnout31% (48%)   First party Second party Third party   Leader Joe Anderson Tom Crone Richard Kemp Party Labour Green Liberal Democrats Leader's seat N/A,Mayor St Michael's Church Last election 78 seats,67% 1 seat,9.7% 1 seat,16.7% Seats before 73 2 9 Seats won 27 2 0 Se...

 

Music genre

Classification of music by tradition or style A music genre is a conventional category (i.e, genre) that identifies some pieces of music as belonging to a shared tradition or set of conventions.[1] Genre is to be distinguished from musical form and musical style, although in practice these terms are sometimes used interchangeably.[2] Music can be divided into genres in numerous ways, sometimes broadly and with polarity, such as for popular music, as opposed to art music or fol...

Billy Kelleher

Irish politician (born 1968) Billy KelleherMEPMember of the European ParliamentIncumbentAssumed office 2 July 2019ConstituencySouthMinister of State2007–2011Enterprise, Trade and EmploymentTeachta DálaIn officeJune 1997 – July 2019ConstituencyCork North-CentralSenatorIn office14 February 1993 – 25 May 1997ConstituencyNominated by the Taoiseach Personal detailsBornWilliam Kelleher (1968-01-20) 20 January 1968 (age 56)Cork, IrelandPolitical partyIreland: Fianna...

 

Doabi dialect

Dialect of Punjabi Doabi PunjabiNative toDoaba, Indian Punjab and Pakistani PunjabRegionPunjabLanguage familyIndo-European Indo-IranianIndo-AryanNorthwesternPunjabiEastern PunjabiDoabi PunjabiLanguage codesISO 639-3–Glottologdoab1238Doabi is in blue Doabi, also known as Bist Doabi or Jalandhari, is an eastern dialect of the Punjabi language. The dialect is named after the region in which it originated, Doaba or Bist Doab,[1] between the Beas and Sutlej. Its occurrence in parts ...

 

Gros Ventre

Native American group of north-central MontanaAtsina redirects here. For other uses, see Atsina (disambiguation). For other uses, see Gros Ventre (disambiguation). Ethnic group Aaniiihʔɔʔɔɔ̋ɔ́niinénnɔhAssiniboin Boy, a Gros Ventre man, photo by Edward S. CurtisTotal population3,682 (2000 census)Regions with significant populationsUnited States (Montana)[1]LanguagesEnglish, Gros VentreReligionRoman Catholicism, Sun Dance,[2] traditional religion[3]Related ethn...

Tuff Hedeman

American bull rider Tuff HedemanHedeman at Las Vegas Motor Speedway in 2024BornRichard Neale Hedeman (1963-03-02) March 2, 1963 (age 61)[1]El Paso, Texas, U.S.Alma materSul Ross State UniversityOccupationsBull riding event producerRancher and team roperRetired rodeo contestantYears active1980-1993; 1995-1998 (as a professional bull rider)Spouse(s)Tracy Stepp (married 1986-2015)Liz Rippetoe (married 2021-present)Children4 Richard Neale Tuff Hedeman (born March 2, 1963) i...

 

جبال السروات

18°16′02″N 42°22′05″E / 18.267222222222°N 42.368055555556°E / 18.267222222222; 42.368055555556 جبل السروات جانب من جبال السروات قرب الباحة المطلة على تهامة عسير الموقع  السعودية  اليمن إحداثيات 18°16′02″N 42°22′05″E / 18.267222222222°N 42.368055555556°E / 18.267222222222; 42.368055555556   الارتفاع 3666 متر  ا�...