Загвар:Геохронологи

Чөлөөт нэвтэрхий толь — Википедиагаас
Харайх: Удирдах, Хайлт
  1. Paleontologists often refer to faunal stages rather than geologic (geological) periods. The stage nomenclature is quite complex. See The Paleobiology Database. 2006-03-19-д хандсан. for an excellent time ordered list of faunal stages.
  2. Dates are slightly uncertain with differences of a few percent between various sources being common. This is largely due to uncertainties in radiometric dating and the problem that deposits suitable for radiometric dating seldom occur exactly at the places in the geologic column where they would be most useful. The dates and errors quoted above are according to the International Commission on Stratigraphy 2004 time scale. 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.
  3. 3.0 3.1 Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. However, the International Commission on Stratigraphy has recently decided to stop endorsing the terms Quaternary and Tertiary as part of the formal nomenclature.
  4. 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). For further discussion of the dating of this epoch, see Holocene.
  5. 5.0 5.1 In North America, the Carboniferous is subdivided into Mississippian and Pennsylvanian Periods.
  6. 6.0 6.1 6.2 6.3 the Precambrian is also known as Cryptozoic.
  7. 7.0 7.1 7.2 7.3 7.4 7.5 The Proterozoic, Archean and Hadean are often collectively referred to as the Precambrian Time or sometimes, also the Cryptozoic.
  8. 8.00 8.01 8.02 8.03 8.04 8.05 8.06 8.07 8.08 8.09 8.10 8.11 Defined by absolute age (Global Standard Stratigraphic Age).
  9. 9.0 9.1 Though commonly used, the Hadean is not a formal eon and no lower bound for the Eoarchean has been agreed upon. The Hadean has also sometimes been called the Priscoan or the Azoic.