The Marystown Group is a Neoproterozoic stratigraphic group of predominantly volcanic sediments – subaerially deposited ash flow tuffs from rhyolites and alkali basalts[2] (with some minor sedimentary strata – red to green siltstones to conglomerates[2] – interleaved), with a central sandstone unit, cropping out in Newfoundland.

[1] It is likely to be temporally equivalent (more or less) to the Love Cove Group, Connaigre Bay Group, Long Harbour Group and Rock Harbour Group.

[1] More accurate/precise dates suggest that the formation is 580-570 Ma (younger than stated in the box above, which uses U-Pb dates).

[3] This geology article is a stub.

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