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In recent years it has become clear that many shallow‐marine heterolithic and mudstone‐dominated successions are deposited as mud belts forming part of subaqueous deltas that are related to major fluvial sources either upstream or along shore. Here the Havert Formation is presented as an ancient example of this kind of system. The Havert Formation in the south‐western Barents Sea represents shelf margin clinoforms consisting predominantly of heterolithic deposits. Sediments were mainly derived from the east (Ural Mountains), but a smaller system prograded northward from Fennoscandia. The Havert Formation holds a lot of interest due to: (i) its stratigraphic position, directly above the Permo–Triassic boundary and contemporaneous to the emplacement of the Siberian Traps; (ii) the fact that it represents the first siliciclastic input in the south‐western Barents Sea and it shows interaction between Uralian‐derived and Fennoscandian‐derived sediments; and (iii) its hydrocarbon potential. This study is focused on a detailed sedimentological analysis of cored intervals of the (Ural‐derived) Havert Formation, in combination with seismic interpretation, well‐log correlations and palynological analysis of the Havert and overlying Klappmyss formations. The cored intervals belong to the shelf environment of the Havert shelf‐margin clinoforms (300 to 500 m thick). This sedimentological analysis distinguishes six facies associations, spanning from tidally‐influenced channels at the shoreline to mud‐rich subaqueous platform and foresets of the subaqueous delta. Seismic lines and well‐log correlations show the larger‐scale evolution of the Ural‐derived Havert Formation, characterized by episodes of low‐accommodation and high‐accommodation. The palynological analyses provide the first detailed study of the Havert Formation in the Nordkapp Basin, revising its depositional age in the region as Induan to early Olenekian (Smithian). Furthermore, they strengthen the environmental interpretation; palynofacies present on the shelf record flora of tidally‐influenced coastal plains, whereas the palynofacies in the deep‐water slope contain only amorphous organic matter.

The Barents Sea region of Arctic Norway preserves a thick succession of marine and deltaic Triassic strata that yield an abundant and diverse association of terrestrial and marine palynomorphs. Despite being the principal means for dating and correlation across this vast region, the Upper Triassic palynozonal resolution has remained relatively low. This is problematic due to the thickness of the Upper Triassic Series and since this corresponds to the longest of the three Triassic epochs. This paper presents a refined Middle–Upper Triassic palynozonation for the region, based on a detailed investigation of multiple localities ranging from the Svalbard Archipelago to the southern Barents Sea. The zonation comprises eleven spore-pollen zones: the Carnisporites spiniger, Triadispora obscura and Protodiploxypinus decus zones (Anisian), the Echinitosporites iliacoides Zone (Ladinian), the Semiretisporis hochulii, Podosporites vigraniae, Leschikisporis aduncus, and Protodiploxypinus spp. zones (Carnian), the Classopollis torosus, and Quadraeculina anellaeformis zones (Norian), and the Ricciisporites spp. Zone (Rhaetian). Additionally, two new dinoflagellate cyst zones are defined: the Rhaetogonyaulax arctica (upper Carnian – lower Norian) and Rhaetogonyaulax rhaetica (lower Norian) zones. Three new age-significant palynomorph taxa are described: Kyrtomisporis moerki sp. nov., Podosporites vigraniae sp. nov. and Semiretisporis hochulii sp. nov. The revised palynozonation is compared with previous palynozonal schemes for the Greater Barents Sea region, and its relationship to Triassic palaeoclimate, palaeoenvironments and sequence stratigraphy is discussed.

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The records of dinoflagellate cysts from the Late Triassic, the time during which they first appear abundantly in the geological record, are reviewed. Most of the Triassic palynological literature pertains to terrestrial palynomorphs, thus it is challenging to establish a global picture of the temporal and spatial distribution of Late Triassic dinoflagellate cyst around the supercontinent of Pangea. Moreover, data on Late Triassic dinoflagellate cysts are dispersed, and there are currently no records of dinoflagellate cysts from many marine successions. With the exception of an Australian record of the dinoflagellate cyst Sahulidinium ottii from the late Mid Triassic, and a possible early Carnian occurrence of, among others, Rhaetogonyaulax in the Swiss Alps, cyst-forming dinoflagellates first appeared relatively synchronously around Pangea from the late Carnian. There are three to six species of pre-Norian species globally, whereas species richness exceeded 25 by the end of the Norian. During the Rhaetian, marine seaways had gradually opened due to sustained continental breakup, allowing the expansion of dinoflagellates into many European basins. New species are present, some known only from restricted areas, whereas others like Dapcodinium appear to have a global distribution. The majority of Triassic dinoflagellate cyst taxa do not extend into the Jurassic.