紀 (地質學)

地质时间的细分; 比一个地质代(Era)短,比一个世(Epoch)要长
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年代地層學
岩段(地層
地質年代學
時間間隔
說明
共有4個,大於5億年
共有14個,數億年
共有22個,數千萬至數億年
共有34個,數千萬年
共有99個,數百萬年
小於期,國際地層委員會(ICS)不使用
規範用法:恐龍生活在侏羅紀(時間),恐龍化石在侏羅系地層中找到。上、下修飾年代地層單位。早、晚修飾地質年代單位。(例:下白堊統對應早白堊世)

(period)是地質學上的時間單位,將區分為更小的時間周期,同理區分為更小的周期。在地球科學里岩石、尤其是成序列的岩石叫地層。

對存在有序排列的「柱狀岩石」組成部分,其具體形成的時期,原因都是地質研究的重點。貼切的時間單位通常意味着對應有相似特徵的岩石地層單位,這種特徵同時發生的其他地方作為岩層沉積物被掩埋在地下。

地質年代參照表


參見

參考資料

  1. ^ Paleontologists often refer to faunal stage英語faunal stages rather than geologic (geological) periods. The stage nomenclature is quite complex. For an excellent time-ordered list of faunal stages, see The Paleobiology Database. [2006-03-19]. 
  2. ^ 2.0 2.1 所有全球年代地層單位均由其底界的全球界線層型剖面和點位(GSSP)界定,包括長期由全球標準地層年齡(GSSA)界定的太古宇和元古宇各單位。斜體代表非正式名稱或尚未命名單位的臨時名稱。圖件及已批准GSSP的詳情參見國際地層委員會官網。GSSP被標記為*,而GSSA被標記為+
    年齡值仍在不斷修訂;顯生宇和埃迪卡拉系的單位不能由年齡界定,而只能由GSSP界定。顯生宇中沒有確定GSSP或精確年齡值的單位,則標註了近似年齡值(~)。
  3. ^ References to the "Post-Cambrian Supereon" are not universally accepted, and therefore must be considered unofficial.
  4. ^ Historically, the 新生代 has been divided up into the 第四紀 and 第三紀 sub-eras, as well as the 新近紀 and 古近紀 periods. The 2009 version of the ICS time chart recognizes a slightly extended Quaternary as well as the Paleogene and a truncated Neogene, the Tertiary having been demoted to informal status.
  5. ^ 5.0 5.1 5.2 5.3 5.4 5.5 For more information on this, see the following articles: 地球大氣層, 二氧化碳, Carbon dioxide in the Earth's atmosphere英語Carbon dioxide in the Earth's atmosphere, global warming, 氣候變遷, Image:Phanerozoic_Carbon_Dioxide.png, Image:65 Myr Climate Change.png, Image:Five Myr Climate Change.png, and Template:DF temperature
  6. ^ 6.0 6.1 在北美,石炭紀被細分為 Mississippian英語Mississippian and Pennsylvanian英語Pennsylvanian Periods.
  7. ^ 7.0 7.1 上石炭紀地質在歐美及中國均以盛產煤炭著名,因此便以石炭紀為此時代地層的名稱,但在美國則以密士西必紀作為下石炭紀,另以賓夕法尼亞紀稱上部石炭紀。[1]
  8. ^ The Precambrian is also known as Cryptozoic.
  9. ^ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 9.7 The Proterozoic, Archean and Hadean are often collectively referred to as the Precambrian Time or sometimes, also the Cryptozoic.
  10. ^ The age of the oldest measurable craton, or continental crust, is dated to 3600–3800 Ma
  11. ^ Geology.wisc.edu
  12. ^ Bowring, Samuel A.; Williams, Ian S. Priscoan (4.00–4.03 Ga) orthogneisses from northwestern Canada. Contributions to Mineralogy and Petrology. 1999, 134 (1): 3. Bibcode:1999CoMP..134....3B. doi:10.1007/s004100050465.  The oldest rock on Earth is the Acasta Gneiss英語Acasta Gneiss, and it dates to 4.03 Ga, located in the Northwest Territories of Canada.