Article: Micropalaeontology of the Late Proterozoic Veteranen Group, Spitsbergen
Shales and siltstones of the Upper Proterozoic Veteranen Group, Spitsbergen, contain abundant and well-preserved microfossil populations. Plankton assemblages from open coastal deposits include a number of taxa previously known from Upper Riphean sequences in Scandinavia, the Soviet Union, and North America. Microfossils from more restricted coastal environments are dominated by small coccoidal unicells and filamentous sheaths of probable cyanobacteria, with locally abundant rod-shaped fossils of blue-greens or other bacteria. Biostratigraphic considerations indicate that the Veteranen Group, which comprises the earliest unmetamorphosed sedimentary sequence in Spitsbergen, was deposited between 800 and 900 Ma ago; this nearly 4000 m sequence was deposited within a relatively brief interval during the early stages of subsidence in a basin that eventually opened to become lapetus. The preservation of delicate prokaryotic microfossils in lagoonal black shales contributes to the resolution of systematic problems arising from the development of two distinct research traditions in Precambrian palaeontology.