Mall Bay Formation

Mall Bay Formation
Stratigraphic range: Ediacaran 608–580  Ma PreꞒ Ꞓ O S D C P T J K Pg N [1]
Type	Formation
Unit of	Conception Group
Underlies	Gaskiers Formation [2]
Thickness	1000 m (3,280 ft)
Lithology
Primary	Siliciclastic siltstones
Other	Mudstone, Sandstone
Location
Region	Newfoundland and Labrador
Country	Canada
Outcrop distribution on Avalon peninsula, Newfoundland

The Mall Bay Formation is an Ediacaran formation, cropping out in Newfoundland and possibly elsewhere. It is part of the Conception Group, underlying the Gaskiers Formation. ^{[2] [1]}

A recent study has found that this formation preserves evidence that the Gaskiers glaciation, which had previously been restricted to the Gaskiers Formation and only lasting roughly 1 million years, had actually begun a lot earlier than originally thought. This has been inferred through the discovery of glacial deposits like dropstones and clasts some 500 m below the Gaskiers base, giving the Gaskiers glaciation a duration of somewhere between 1.05 Ma to 4.8 Ma, up from the previous estimate of 350 ka to 1.6 Ma. ^[1]

References

1. Fitzgerald, Danielle M.; Narbonne, Guy M.; Pufahl, Peir K.; Dalrymple, Robert W. (June 2024). "The Mall Bay Formation (Ediacaran) and the protracted onset of the Gaskiers glaciation in Newfoundland, Canada". Precambrian Research. 405 107369. doi: 10.1016/j.precamres.2024.107369 .
2. A.G. Liu; D. McIlroy (September 2014). "Horizontal Surface Traces from the Fermeuse Formation, Ferryland (Newfoundland, Canada), and their Place within the Late Ediacaran Ichnological Revolution" (PDF). Geological Association of Canada - Special Paper (9).^{[ dead link ]}