Wynniatt Formation

The Wynniatt Formation is a geologic formation in Nunavut. It preserves enigmatic fossils dating back to the Middle to Late Tonian period, around 850 Ma - 760 Ma.^[3]

Wynniatt Formation
Stratigraphic range: Tonian 848+-49–761+-41 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓ [1]
Type	Geological Formation
Sub-units	Member 1, 2, 3 and 4
Underlies	Kilian Formation [2]
Overlies	Boot Inlet Formation [2]
Thickness	500 - 800 m (1,640 - 2,624 ft)
Lithology
Primary	Dolomite
Other	Mudstone, Siltstone, Quartz arenite, Sandstone, Limestone, Gabbro
Location
Region	Nunavut
Country	Canada

Paleoenviroments

Due to the large thickness of the Wynniatt Formation, it is broken up into 4 Members, simply named "Member" 1 - 4, and from the rocks contained within these 4 members, a rough idea of what the paleoenviroments may have looked across the formation are as follows:^[2]

- Member 1 : Periodically exposed inter-tidal mudflat.

- Member 2 : Shallow sub-tidal to inter-tidal with layers of microbial mat, and is also the fossil bearing member.^[3]

- Member 3 : Extensive shelf-marginal reef complex, which itself is overlain by deposits of lagoons and a back-reef agal flat.

- Member 4 : Cycles of shallow sub-tidal to inter-tidal.

Paleobiota

After Butterfield, 2005.^[3]

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	Notes	Images
Cheilofilum	C. hysteriopsis	Enigmatic 1.2mm long filamentous organism.
Chuaria	Chuaria sp.	Enigmatic fossil, possibly synonymous with Tawuia.
Clavitrichoides	Clavitrichoides sp.	Enigmatic filamentous organism, most material from this formation are possibly less well preserved Cheilofilum.
Osculosphaera	Osculosphaera sp.	Enigmatic filamentous organism.
Plicatosphaeridium	P. impostor	Enigmatic filamentous organism.
Tappania	Tappania sp.	Acanthomorph acritarch.
Tawuia	Tawuia sp.	Enigmatic fossil, possibly an alga.

See also

• Earth sciences portal
• Canada portal
• Paleontology portal

• List of fossiliferous stratigraphic units in Nunavut