Fortunian

Fortunian
	541.0 ± 1.0 – ~529 Ma PreꞒ Ꞓ O S D C P T J K Pg N
	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 — – N; ♇ P; a; l; e; o; z; o; i; c Ediacaran C; a; m; b; r; i; a; n O T; e; r; r; e; n; e; u; v; i; a; n; ; S; e; r; i; e; s; ; 2 M; i; a; o; l; i; n; g. F; u; r; o; n; g. E Fortunian; "Stage 2" "Stage 3" "Stage 4" Wuliuan Drumian Guzhangian Paibian Jiangshanian "Stage 10" Tremadocian ← Orsten Fauna ← Burgess Shale ← Kaili biota ← Archaeocyatha extinction ← Emu Bay Shale ← Sirius Passet biota ← Chengjiang biota ← First Trilobites ← SSF diversification, first brachiopods & archaeocyatha ← First halkieriids, mollusсs, hyoliths SSF ← Baykonurian glaciation ← Dresbachian extinction 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	First appearance of small shelly fauna or Archaeocyathids
Upper boundary GSSP candidate section(s)	None

The Fortunian age marks the beginning of the Phanerozoic eon, the Paleozoic era, and the Cambrian period. It is the first of the two stages of the Terreneuvian series. Its base is defined as the first appearance of the trace fossil Treptichnus pedum 541 million years ago. The top of the Fortunian which is the base of the Stage 2 of the Cambrian has not been formally defined yet, but will correspond to the appearance of an Archeocyatha species or "Small shelly fossils" approximately 529 million years ago.[3]

The name Fortunian is derived from a part of the Burin Peninsula, the town of Fortune near the GSSP and Fortune Bay.[4]

GSSP

The type locality (GSSP) of the Fortunian stage is in Fortune Head, at the northern edge of the Burin Peninsula, Newfoundland, Canada (47.0762°N 55.8310°W / 47.0762; -55.8310). This GSSP coincides with the base of the Terreneuvian series, the Precambrian-Cambrian boundary and the beginning of the Phanerozoic. 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 2nd 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) is 400 m above the boundary. The first trilobites appear 1400 m above the boundary which corresponds to the beginning of the Branchian Series.[5]

Palaeontology

Agnathans

Agnathans of the Fortunian
Taxa	Presence	Location	Description	Images
Haikouichthys	Fortunian-"Stage 3"
Myllokunmingia	Fortunian-"Stage 3"	Chengjiang, Maotianshan shales, Yuanshan Member, Qiongzhusi Formation, Yunnan Province, China

Dinocarididans

Dinocarididans of the Guzhangian
Taxa	Presence	Location	Description	Images
Peytoia	Fortunian-Guzhangian	Phyllopod bed, Walcott Quarry, Burgess Shale, British Columbia, Canada; Koscierzyna borehole, Kashubia, Poland

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.
"Global Boundary Stratotype Section and Point". International Commission of Stratigraphy. Archived from the original on 15 November 2012. Retrieved 2 November 2012.
Landing, E. "THE BASE OF THE CAMBRIAN: TERRENEUVIAN SERIES AND FORTUNIAN STAGE" (PDF). Retrieved 2 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.

External links

Martin, Anthony (Tony). "Out of One's Depth in the Ediacaran". Retrieved 27 November 2013.
Martin, Anthony (Tony). "Mistaken Point and the Limits of Actualism". Retrieved 27 November 2013.
Album of the Ichnia 2012 conference at Fortune Head

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[Landing2007-1] 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.

[2] Landing, Ed. "THE BASE OF THE CAMBRIAN: TERRENEUVIAN SERIES AND FORTUNIAN STAGE". International Subcommission on Cambrian Stratigraphy. Retrieved 13 December 2020.

[GSSP_Web-3] "Global Boundary Stratotype Section and Point". International Commission of Stratigraphy. Archived from the original on 15 November 2012. Retrieved 2 November 2012.

[Landing_Fortunian-4] Landing, E. "THE BASE OF THE CAMBRIAN: TERRENEUVIAN SERIES AND FORTUNIAN STAGE" (PDF). Retrieved 2 November 2012.

[Brasier_1994-5] 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.