Cambrian

Cambrian
Cambrian
538.8 ± 0.2 – 485.4 ± 1.9 Ma PreЄ Є O S D C P T J K Pg N
	Earth in the middle of the Cambrian Period
Chronology
	සැකිල්ල:Cambrian 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
First proposed by	Adam Sedgwick, 1835
Time span formality	Formal
Lower boundary definition	Appearance of the Ichnofossil Treptichnus pedum
Lower boundary GSSP	Fortune Head section, Newfoundland, Canada; 47°04′34″N 55°49′52″W / 47.0762°N 55.8310°W
GSSP ratified	1992
Upper boundary definition	FAD of the Conodont Iapetognathus fluctivagus.
Upper boundary GSSP	Greenpoint section, Green Point, Newfoundland, Canada; 49°40′58″N 57°57′55″W / 49.6829°N 57.9653°W
GSSP ratified	2000
Atmospheric and climatic data
Sea level above present day	Rising steadily from 4 m to 90 m

Cambrian Period යනු Paleozoic යුගයේ පළමු කාලපරිච්ඡේදය, එනම් වසර මිලියන 539-485 කට පෙර යුගය වේ.

ගැලරිය

Stromatolites of the Pika Formation (Middle Cambrian) near Helen Lake, Banff National Park, Canada
Trilobites were very common during this time
Anomalocaris was an early marine predator, among the various arthropods of the time
Opabinia was a creature with an unusual body plan; it was probably related to arthropods
Pikaia was a stem-chordate from the Middle Cambrian
Protichnites were the trackways of arthropods that walked Cambrian beaches
Hallucigenia sparsa was a member of group lobopodian, that is considered to related to modern velvet worms.
Cambroraster falcatus was a large arthropod for the era

Cambrian–Ordovician extinction event – circa 488 mya
Dresbachian extinction event—circa 499 mya
End Botomian extinction event—circa 513 mya
List of fossil sites (with link directory)
Type locality (geology), the locality where a particular rock type, stratigraphic unit, fossil or mineral species is first identified

^ Brasier, Martin; Cowie, John; Taylor, Michael. "Decision on the Precambrian-Cambrian boundary stratotype" (PDF). Episodes. 17. සම්ප්‍රවේශය 6 December 2020.
^ Cooper, Roger; Nowlan, Godfrey; Williams, S. H. (March 2001). "Global Stratotype Section and Point for base of the Ordovician System" (PDF). Episodes. 24 (1): 19–28. doi:10.18814/epiiugs/2001/v24i1/005. සම්ප්‍රවේශය 6 December 2020.
^ Haq, B. U.; Schutter, SR (2008). "A Chronology of Paleozoic Sea-Level Changes". Science. 322 (5898): 64–8. Bibcode:2008Sci...322...64H. doi:10.1126/science.1161648. PMID 18832639. S2CID 206514545.