Cretaceous
From Wikipedia, the free encyclopedia
Cretaceous යනු මීට වසර මිලියන 145-66 කට පෙර, එන්ම් Mesozoic යුගයේ තුන්වන සහ අවසාන කාලපරිඡ්ඡේදය වේ.
Quick Facts Chronology, Etymology ...
Cretaceous | |
---|---|
~145.0 – 66.0 Ma | |
Chronology | |
සැකිල්ල:Cretaceous graphical timeline | |
Etymology | |
Name formality | Formal |
Usage information | |
Celestial body | Earth |
Regional usage | Global (ICS) |
Time scale(s) used | ICS Time Scale |
Definition | |
Chronological unit | Period |
Stratigraphic unit | System |
Time span formality | Formal |
Lower boundary definition | Not formally defined |
Lower boundary definition candidates |
|
Lower boundary GSSP candidate section(s) | None |
Upper boundary definition | Iridium-enriched layer associated with a major meteorite impact and subsequent K-Pg extinction event |
Upper boundary GSSP | El Kef Section, El Kef, Tunisia 36.1537°N 8.6486°E / 36.1537; 8.6486 |
GSSP ratified | 1991 |
Close