Lithostratigraphy of the Cambrian? – Lower Ordovician Bell Island and Wabana groups of Bell, Little Bell, and Kellys islands, Conception Bay, eastern Newfoundland

Abstract

The Upper Cambrian? – Arenigian succession of Bell, Little Bell, and Kellys islands, Conception Bay, eastern Newfoundland, consists of at least 1500 m of interbedded micaceous sandstones, siltstones, shales, and ironstones. The succession has previously been formally subdivided into only two groups, namely, a lowermost Bell Island Group and an overlying Wabana Group. The existing lithostratigraphic nomenclature below group level has, to date, only been informally proposed and is therefore herein formally revised. The lowermost Bell Island Group comprises from base to top the Kellys Island, Little Bell Island, Beach, Redmans, Ochre Cove, and Dominion formations. Of these, the Ochre Cove and Dominion formations are newly proposed and the Beach Formation is considerably revised from its historical usage. The Beach Formation contains two newly proposed members, the McGraw and Eastern Head members, both of which in previous nomenclature were informally referred to as "beds." The disconformably overlying Wabana Group comprises from base to top the Powers Steps, Scotia, Grebes Nest Point, Gull Island, and Gravel Head formations. Of these, the Gravel Head Formation is revised from its historical usage and the remainder are newly proposed. The Powers Steps Formation contains a newly proposed member, the Youngsters Gulch Member, previously in part referred to informally as the "pyrite bed."

An Arenig graptolite from Bell Island, eastern Newfoundland - its biostratigraphic and paleogeographic significance

“…2,3), the basal formation of the Wabana Group (Ranger, 1979;Ranger et al, 1984;King et al, 1988). The graptolites were first recorded by Van Ingen (1914, p. 138) as Didymograptus nitidus (J.…”

“…The first detailed description of the stratigraphy was published by Van Ingen in 1914, since which time a number of authors have discussed aspects of the sedimentology, stratigraphy and origin of the iron ore deposits. Ranger et al (1984) proposed the lithostratigraphic classification currently in use; shoreline sediments assigned to the Upper Cambrian to Lower Ordovician Bell Island Group are overlain by somewhat deeper deltaic and shallow marine deposits of the Arenig Wabana Group on the north-western part of the island. Full details regarding stratigra- phy and depositional environments have been given recently by King et al (1988) and Pickerill et al (1988).…”

A note on the occurrence of Arthrophycus in the Bell Island Group of eastern Newfoundland

“…The Beach Formation contained 26 ichnogenera, 78 ichnospecies and 2 vernacular ichnotaxa and represented the most diverse formation (ichnologically) of the entire sequence. In part this high diversity resulted from the considerable range of lithologies constituting the formation, conducive to preservation of trace fossils by toponomic proc esses, and the variety of marginal and shallow marine environ ments represented within it (see Ranger, 1979;Ranger et al, 1984;Pickerill et al, 1988;Fillion and Pickerill, 1990). The occurrence of Arthrophycus, as described herein, further in creases the ichnogeneric diversity of this formation.…”

“…As outlined by Ranger et al (1984), Pickerill et al (1988) and Fillion and Pickerill (1990), these strata were depos ited in a storm-dominated shelf and deltaic environment.…”

Late Neoproterozoic Avalonian and related peri-Gondwanan rocks of the Newfoundland Appalachians

“…Deposition of black micaceous shale and siltstone in the Late Cambrian continued into the Tremadocian (van Ingen, 1914;Jenness, 1963;Martin and Dean, 1981), when micaceous sandstone, quartz arenite, siltstone, and oolitic hematite accumulated. In the Arenig, a succession of shale, sandstone, and oolitic hematite was deposited in a tide-dominated delta system (Ranger et al, 1984;Pickerell et al, 1988).…”