Precambrian
Appearance
Precambrian | |
---|---|
Chronology | |
Proposed subdivisions | SeeProposed Precambrian timeline |
Etymology | |
Synonym(s) | Cryptozoic |
Usage information | |
Celestial body | Earth |
Regional usage | Global (ICS) |
Time scale(s) used | ICS Time Scale |
Definition | |
Chronological unit | Supereon |
Stratigraphic unit | Supereonthem |
Time span formality | Informal |
Lower boundary definition | Formation of theEarth |
Lower boundary GSSP | N/A |
GSSP ratified | N/A |
Upper boundary definition | Appearance of theIchnofossilTreptichnus pedum |
Upper boundary GSSP | Fortune Head section,Newfoundland,Canada 47°04′34″N55°49′52″W/ 47.0762°N 55.8310°W |
GSSP ratified | 1992 |
Precambrian(හෝPre-Cambrian,සමහර විටක කෙටිකොට දක්වන පරිදිpꞒ,හෝCryptozoic) යනු පෘථිවි ඉතිහාසයේ වසර මිලියන 4600-539 කට පෙර යුගය වේ.
ආශ්රිත
[සංස්කරණය]- Phanerozoic– fourth and current eon of the geological timescale
මූලාශ්ර
[සංස්කරණය]
භාහිර සබැඳි
[සංස්කරණය]Precambrianහා සබැඳි මාධ්ය විකිමාධ්ය කොමන්ස් හි ඇත.
- Late Precambrian Supercontinent and Ice House Worldfrom the Paleomap Project