Precambrian Time
(Cryptozoic, Primordial)
From 4567.17 +/- 0.7 To 542 +/- 0.3 Ma
Start Defined By: Formation of Earth
End Defined By: Trace fossil, lowest occurrence of Treptichnus (Phycodes)
pedum. Near base of negative carbon-isotope excursion.
Start Based On: Amelin, Krot, Hutcheon, and Ulyanov, "Lead Isotopic Ages of
Chondrules and Calcium-Aluminum-Rich Inclusions", _Science_, Sept. 6,
2002.
End Based On: Amthor et. al., "Extinction of Cloudinia and Namacalathus at
the Precambrian-Cambrian boundary in Oman", _Geology_, v. 31, p. 431-434,
2003.
Comment: Cryptozoic is sometimes identified as excluding the Hadean
-- Followed By --
Eon: Phanerozoic (542 - -5.5012e-005)
Era: Paleozoic (542 - 251)
Period: Cambrian (542 - 488.3)
Epoch: Early Cambrian (542 - 513)
Chinese Stage: Meishuchuan (542 - 532)
Russian-Kazakhian Stage: Nemakit-Daldynian (542 - 534)
-- Contains the Following Eons --
Eon: Hadean (4567.17 - 3800)
Eon: Archean (3800 - 2500)
Eon: Proterozoic (2500 - 542)
|
