Ives Head Formation
| Ives Head Formation | |
|---|---|
| Stratigraphic range: Ediacaran | |
Ives Head, the locality after which the formation is named. | |
| Type | Formation |
| Unit of | Blackbrook Group |
| Sub-units | South Quarry Slump Breccia, Lubcloud Greywackes, Morley Lane Tuffs Members |
| Underlies | Blackbrook Reservoir Formation[2] |
| Thickness | 820 m (2,690 ft)[2] |
| Lithology | |
| Primary | Tuff |
| Other | Breccia, Greywacke, Sandstone, Dacite |
| Location | |
| Region | Leicestershire |
| Country | United Kingdom |
| Type section | |
| Named for | Ives Head |
The Ives Head Formation is a geologic formation in Leicestershire, England. It forms part of the Blackbrook Group within the Charnwood Forest succession. The unit preserves rocks of Lower Ediacaran age and is named after the locality of Ives Head.
Paleobiota
The Ives Head Formation contains the oldest known fossils within the Charnian Supergroup, occurring on the Lubcloud surface. Preliminary zircon ages suggest that these fossils may be older than the Gaskiers glaciation if the proposed dating is confirmed, with the base of the formation lying just below c. 611 Ma.[1] This would place them among the oldest currently recognised Ediacaran assemblages; however, comparisons with units such as the c. 580 Ma Rocky Harbour Formation in Newfoundland and Labrador and the c. 602 Ma Lantian Formation in China remain tentative, as the dating of the Charnian succession requires further refinement.[3]
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Ivesheadiomorph
| Genus | Species | Notes | Images |
|---|---|---|---|
| Blackbrookia[4][3][5] |
|
Poorly preserved organism, possibly of a petalonamid. | |
| Ivesheadia[4][5] |
|
Poorly preserved organism. | |
| Shepshedia[4][5] |
|
Poorly preserved organism. |
See also
References
- Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Archived from the original on 25 March 2022. Retrieved 17 December 2021.
- ^ a b Noble, Stephen R.; Condon, Daniel J.; Carney, John N.; Wilby, Philip R.; Pharaoh, Timothy C.; Ford, Trevor D. (January 2015). "U-Pb geochronology and global context of the Charnian Supergroup, UK: Constraints on the age of key Ediacaran fossil assemblages". Geological Society of America Bulletin. 127 (1–2): 250–265. doi:10.1130/B31013.1.
- ^ a b Moseley, John; Ford, Trevor. "The Sedimentology of the Charnian Supergroup" (PDF). Mercian Geologist.
- ^ a b Kenchington, Charlotte G.; Harris, Simon J.; Vixseboxse, Philip B.; Pickup, Chris; Wilby, Philip R. (June 2018). "The Ediacaran fossils of Charnwood Forest: Shining new light on a major biological revolution". Proceedings of the Geologists' Association. 129 (3): 264–277. doi:10.1016/j.pgeola.2018.02.006.
- ^ a b c H. E. Boynton, T. D. Ford (1995). "Ediacaran Fossils from the Precambrian (Charnian Supergroup) of Charnwood Forest, Leicestershire, England". Mercian Geologist. 13 (4): 165–182.
- ^ a b c Wilby, Philip R.; Carney, John N.; Howe, Michael P.A. (1 July 2011). "A rich Ediacaran assemblage from eastern Avalonia: Evidence of early widespread diversity in the deep ocean". Geology. 39 (7): 655–658. doi:10.1130/G31890.1.