The Mall Bay Formation is an

Ediacaran The Ediacaran ( ) is a geological period of the Neoproterozoic geologic era, Era that spans 96 million years from the end of the Cryogenian Period at 635 Million years ago, Mya to the beginning of the Cambrian Period at 538.8 Mya. It is the last ...

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondary ...

, cropping out in

Newfoundland Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the population ...

and possibly elsewhere. It is part of the Conception Group, underlying the Gaskiers Formation. A recent study has found that this formation preserves evidence that the

Gaskiers glaciation The Gaskiers glaciation is a period of widespread glacial deposits (e.g. diamictites) that lasted under 340,000 years, between 579.88 ± 0.44 and 579.63 ± 0.15 million years ago — i.e. late in the Ediacaran Period — making it the last major ...

, 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

dropstone Dropstones are isolated fragments of rock found within finer-grained water-deposited sedimentary rocks or pyroclasts, pyroclastic beds. They range in size from small pebbles to boulders. The critical distinguishing feature is that there is eviden ...

s and

clasts Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks b ...

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.

References

{{Reflist Ediacaran Newfoundland and Labrador