Cambrian
Cambrian Period යනු Paleozoic යුගයේ පළමු කාලපරිච්ඡේදය, එනම් වසර මිලියන 539-485 කට පෙර යුගය වේ.
| Cambrian | |
|---|---|
 Earth in the middle of the Cambrian Period | |
| Chronology | |
| 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[1] |
| 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[2] |
| Atmospheric and climatic data | |
| Sea level above present day | Rising steadily from 4 m to 90 m[3] |
ගැලරිය
සංස්කරණය-
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
ආශ්රිත
සංස්කරණය- 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
මූලාශ්ර
සංස්කරණය- ^ 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.
භාහිර සබැඳි
සංස්කරණය
Cambrian හා සබැඳි මාධ්ය විකිමාධ්ය කොමන්ස් හි ඇත.
- Cambrian period on In Our Time at the BBC
- Biostratigraphy සංරක්ෂණය කළ පිටපත 2021-02-26 at the Wayback Machine – includes information on Cambrian trilobite biostratigraphy
- Dr. Sam Gon's trilobite pages (contains numerous Cambrian trilobites)
- Examples of Cambrian Fossils
- Paleomap Project
- Report on the web on Amthor and others from Geology vol. 31
- Weird Life on the Mats
- Chronostratigraphy scale v.2018/08 | Cambrian