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Jurassic strata are extensively distributed in offshore areas of Scandinavia, but onshore exposures are mostly restricted to southern Sweden (Skåne), the Danish island of Bornholm, East Greenland, northern Norway (Andøya) and Svalbard. The latest Triassic and Jurassic saw active tectonism in Scandinavia associated with the break-up of Pangaea and rifting in the North Atlantic region and the North Sea. Rifting and the gradual rise in sea level controlled the structural and sedimentological architecture of Scandinavian basins throughout the Jurassic. The Upper Triassic is represented by continental red beds (claystones and arkosic conglomerates) indicative of arid conditions (until the Norian) and by coal measures characteristic of humid conditions (in the Rhaetian). Early Jurassic sedimentation in the region was dominated by fluvial-estuarine systems. Basin subsidence combined with the supply of huge volumes of sediments led to the accumulation of thick sand units on vast coastal plains in the Early and Middle Jurassic. During the Late Jurassic, transgressions led to deposition of extensive marine mud, although sandstones are locally preserved. Paralic depositional environments prevailed during the Late Jurassic and into the Early Cretaceous in southern Scandinavia. Scandinavia hosts a rich Jurassic palaeontological record including fossil plants, sharks, dinosaur footprints, ammonites, belemnites, ichthyosaurs and pliosaurs. Miospores provide the primary tool for biostratigraphic subdivision and correlation of the continental Jurassic sediments, whereas ammonites, dinoflagellates and foraminifera are the main groups employed for marine biostratigraphy. However, much work remains to be completed to achieve a highly resolved zonation scheme that integrates both marine and terrestrial indices.

A sequence in the Upper Silurian Öved-Ramsåsa Group in Scania, Sweden has been investigated sedimentologically and geochemically. This sequence represents a regressive marine succession. The sedimentary structures and the rapid vertical changes in lithologies and the lateral variability of beds indicate a tide-dominated sedimentation in a shallow epeiric sea, where even small oscillations in sea water level and water energy affected sedimentation. The succession of facies shows an upward transition from open marine shallow subtidal/intertidal to lagoonal subtidal/intertidal conditions. These facies changes are accompanied by faunal changes and shifts in major and trace element concentrations. Of particular interest are the presence of radial and cerebroid ooids and evaporite tracers. The radial fabric of the ooids is regarded as primary and it is suggested that these ooids formed in suspension, in the lowenergy subtidal lagoonal environment. Implications for a restriction in water circulation and progressive evaporation, coinciding with the ooid formation are seen in associated sediments of this facies. A salinity increase is demonstrated by the presence of BaSO 4 and elevated values of MgO, NaO and Ba. A high Zr and SiO 2 content, most probably derived from eolian dust, indicate increased aridity and a relative decrease of water transported clastics.

A palynological study of the upper Silurian Ö ved-Ramsåsa Group in Skåne, Sweden yields a well preserved spore assemblage with low relative abundances of marine microfossils. In total, 26 spore taxa represented by 15 genera were identified. The spore assemblage is dominated by long-ranging cryptospore taxa, and the trilete spore Ambitisporites avitus-dilutus. However, key-species identified include Artemopyra radiata, Hispanaediscus lamontii, H. major, H. verrucatus, Scylaspora scripta and Synorisporites cf. libycus. Importantly, Scylaspora klintaensis was identified, allowing correlation with the Klinta 1 drillcore (Skåne). A Ludlow age is inferred for the exposed succession, which agrees well with previous conodont stratigraphy. The organic residue is dominated by phytodebris and spores, but with high relative abundances of acritarchs at two levels, possibly related to flooding surfaces.Based on the palynofacies analysis, a near-shore marine environment is proposed. The close proximity to land is inferred by the high proportions of spores, and the dispersed assemblage most likely represents the local flora growing on delta plains. The palynological signal also infers a stable terrestrial environment and vegetation, in contrast to unstable conditions in the marine environment characterised by ooid formation in an evaporitic environment. Comparisons with coeval spore assemblages from Gotland, Avalonia and Laurentia show relatively close similarities in taxonomic composition at the generic level.