Terreneuvian
The Terreneuvian is the lowermost and oldest series of the Cambrian geological system.[1] Its base is defined by the first appearance datum of the trace fossil Treptichnus pedum around 541 million years ago. Its top is defined as the first appearance of trilobites in the stratigraphic record around 521 million years ago.[3] This series' name was formally accepted by the International Commission on Stratigraphy in 2007.[1]
| Terreneuvian | |
|---|---|
| 541.0 ± 1.0 – ~521 Ma | |
 Delegates from the Ichnia 2012 conference inspect the Global Boundary Stratotype Section and Point (GSSP) for the Ediacaran-Cambrian boundary at Fortune Head Ecological Reserve, Newfoundland, Canada. | |
| Chronology | |
Key events in the Cambrian -540 — – -535 — – -530 — – -525 — – -520 — – -515 — – -510 — – -505 — – -500 — – -495 — – -490 — – -485 — – Major Glacial period Stratigraphic scale of the ICS subdivisions and Precambrian/Cambrian boundary. | |
| Etymology | |
| Name formality | Formal |
| Name ratified | 2007[1] |
| Former name(s) | Cambrian Stage 1 |
| Usage Information | |
| Celestial body | Earth |
| Regional Usage | Global (ICS) |
| Time scale(s) used | ICS Time Scale |
| Definition | |
| Chronological unit | Age |
| Stratigraphic unit | Stage |
| First proposed by | Ed Landing, 2007[2] |
| Time span formality | Formal |
| Lower boundary definition | Appearance of the Ichnofossil Treptichnus pedum |
| Lower boundary GSSP | Fortune Head section, Newfoundland, Canada 47.0762°N 55.8310°W |
| GSSP ratified | 2007 (as base of Terreneuvian and Fortunian)[1] |
| Upper boundary definition | Not formally defined |
| Upper boundary definition candidates | FAD of Trilobites |
| Upper boundary GSSP candidate section(s) | None |
The Fortunian stage and presently unnamed Cambrian Stage 2 are the stages within this series. The Terreneuvian corresponds to the pre-trilobitic Cambrian.[4]
The name Terreneuvian is derived from Terre Neuve, a French name for the island of Newfoundland, Canada, where many rocks of this age are found, including the type section.[1][3]
Type locality
The type locality (GSSP) of the Terreneuvian is in Fortune Head, at the northern edge of the Burin Peninsula, Newfoundland, Canada (47.0762°N 55.8310°W). The outcrops show a carbonate-siliciclastic succession which is mapped as the Chapel Island Formation. The formation is divided into the following members that are composed of peritidal sandstones and shales (Member 1), muddy deltaic and shelf sandstones and mudstones (Member 2A), laminated siltstones (Member 2B and 3) and mudstones and limestones of the inner shelf (Member 4). The Precambrian-Cambrian boundary lies 2.4 m above the base of the second member, which is the lowest occurrence of Treptichnus pedum. The traces can be seen on the lower surface of the sandstone layers. The first calcareous shelled skeletal fossils (Ladatheca cylindrica) are 400 m above the boundary. The first trilobites appear 1400 m above the boundary, which corresponds to the beginning of the Branchian Series.[5]
References
- Landing, Ed; Peng, Shanchi; Babcock, Loren; Geyer, Gerd; Moczydlowska-Vidal, Malgorzata (December 2007). "Global standard names for the Lowermost Cambrian Series and Stage". Episodes. 30 (4): 287–289. doi:10.18814/epiiugs/2007/v30i4/004. Retrieved 13 December 2020.
- Landing, Ed. "THE BASE OF THE CAMBRIAN: TERRENEUVIAN SERIES AND FORTUNIAN STAGE". International Subcommission on Cambrian Stratigraphy. Retrieved 13 December 2020.
- PENG, S.C. & BABCOCK, L.E. 2011. Continuing progress on chronostratigraphic subdivision of the Cambrian System. Bulletin of Geosciences 86(3), 391–396 (1 figure). Czech Geological Survey, Prague. ISSN 1214-1119.
- Li, G. "The Fad of Watsonella Crosbyi". Retrieved 10 November 2012.
- Brasier, Martin; John Cowie; Michael Taylor (1994). "Decision on the Precambrian-Cambrian boundary stratotype" (PDF). Episodes. 17 (1–2): 95–100. Retrieved 14 September 2012.