Late Precambrian Shallow Water Deposits, Banks and Victoria Islands, Arctic Archipelago
The upper Precambrian succession of the southern tip of Banks Island comprises about 900 m of sedimentary rocks intruded by thick gabbro sills. The lowest unit exposed is a cherty stromatolitic carbonate. This is overlain by a thicker unit of sandstones and mudstones. Most of the sequence is considered to be correlative with the Glenelg Formation, which is the basal formation of the late Precambrian Shaler Group of the Minto Arch on Victoria Island. A thick shale unit at the top of the Banks Island Precambrian succession may be correlative with the basal part of the Reynolds Point Formation on Victoria Island.Paleocurrent measurements from the Banks Island rocks indicate transport essentially to the northwest. An abundantly cross-bedded sandy limestone unit in the upper part of the Reynolds Point Formation in the Minto Inlet area of Victoria Island gives a polymodal paleocurrent pattern. This unit was probably deposited in a shallow marine environment under tidal influence. Tidalites have been recognized ...