Terreneuvian
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
Etymology
Name formalityFormal
Name ratified2007[2]
Former name(s)Cambrian Stage 1
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
First proposed byEd Landing, 2007[3]
Time span formalityFormal
Lower boundary definitionAppearance of the Ichnofossil Treptichnus pedum
Lower boundary GSSPFortune Head section, Newfoundland, Canada
47°04′20″N 55°51′52″W / 47.072163°N 55.864398°W / 47.072163; -55.864398
Lower GSSP ratified2007 (as base of Terreneuvian and Fortunian)[2]
Upper boundary definitionNot formally defined
Upper boundary definition candidatesFAD of Trilobites
Upper boundary GSSP candidate section(s)None

The Terreneuvian is the lowermost and oldest series of the Cambrian geological system.[2] Its base is defined by the first appearance datum of the trace fossil Treptichnus pedum around 538.8 million years ago. Its top is defined as the first appearance of trilobites in the stratigraphic record around 521 million years ago.[4] This series' name was formally accepted by the International Commission on Stratigraphy in 2007.[2]

The Fortunian stage and presently unnamed Cambrian Stage 2 are the stages within this series. The Terreneuvian corresponds to the pre-trilobitic Cambrian.[5]

The name Terreneuvian is derived from Terre Neuve, the French name for the island of Newfoundland, Canada, where many rocks of this age are found, including the type section.[2][4]

Type locality

The type locality (GSSP) of the Terreneuvian is in Fortune Head, at the northern edge of the Burin Peninsula, Newfoundland, Canada (47°04′34″N 55°49′52″W / 47.0762°N 55.8310°W / 47.0762; -55.8310). 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 (Series 2).[6]

References

  1. "Chart/Time Scale". stratigraphy.org. International Commission on Stratigraphy.
  2. 1 2 3 4 5 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.
  3. Landing, Ed. "THE BASE OF THE CAMBRIAN: TERRENEUVIAN SERIES AND FORTUNIAN STAGE". International Subcommission on Cambrian Stratigraphy. Retrieved 13 December 2020.
  4. 1 2 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.
  5. Li, G. "The Fad of Watsonella Crosbyi". Retrieved 10 November 2012.
  6. 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.

See also


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