The recent proliferation of stratigraphic studies of delta 13C variation in carbonates and organic C in later Neoproterozoic and basal Cambrian successions (approximately 850-530 Ma) indicates a strong oscillating trend in the C-isotopic composition of surface seawater. Alone, this trend does not adequately characterize discrete intervals in Neoproterozoic time. However, integrated with the vec...

The olenelloid trilobite genus Laudonia Harrington, 1956 was thought to occur widely along the Cordilleran margin of Laurentia in lowermost Dyeran strata (Cambrian Series 2). However, supposed occurrences in the Rosella Formation (Cassiar Mountains, northern British Columbia), the Mural Formation (Cariboo Mountains, east-central British Columbia) and the Poleta Formation (Nevada)--re-examined, ...

Vase-shaped microfossils (VSMs) attributed to testate amoebae occur globally in diverse assemblages Tonian rocks. These have thus been considered a potential biostratigraphic tool, especially for the interval between 789 and 729 Ma. Here we report well-preserved situ VSM assemblage, including several taxa previously as Tonian, within glacially influenced deposits which sedimentological data sup...

An extense systematic description of the Eocene larger foraminiferal faunas recorded in South Pyrenean Basin (Sierras Exteriores) is presented herein. The large dataset provided this work includes both Nummulites and Alveolina species, along with a variety other porcellaneous hyaline taxa lesser biostratigraphic relevance, are represented. foraminifera described correspond mainly to Lutetian (S...