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Abstract

Nothofagaceae fossil leaves and an associated palynoflora from Late Cretaceous sediments of Vega Island, eastern Antarctic Peninsula, are presented. The leaves are described as Nothofagus sp. 1 and Morphotype LDB 1, and come from the Snow Hill Island (late Campanian-early Maastrichtian) and the López de Bertodano (late Maastrichtian) formations, respectively. The palynoflora obtained from levels immediately above and below the Nothofagus sp. 1 and in the same horizon as the Morphotype LDB 1, included terrestrial and marine elements. In the palynoflora associated with Nothofagus sp. 1, conifers are dominant and pollen grains with Nothofagus affinity are represented by four species: Nothofagidites kaitangataensis (Te Punga) Romero 1973 and Nothofagidites senectus Dettmann and Playford 1968, which belong to the ancestral pollen type, as well as Nothofagidites dorotensis Romero 1973 and Nothofagidites sp. of the brassii-type. Cryptogamic spores, marine dinoflagellate cysts and algae, among others, are part of the assemblage. The palynoflora associated with the Morphotype LDB 1 also contains abundant conifer and angiosperm pollen grains with N. dorotensis as the only Nothofagus species recorded. Marine dinoflagellate cysts are scarce while fungi and phytodebris are common elements. The joint presence of marine and non-marine palynomorphs supports a probable nearshore environment at time of deposition for both units. Pollen and spore evidence suggests a mixed conifer and angiosperm forest, with Podocarpaceae and Nothofagus as the main components, and ferns, lycopods, and mosses in the understory. This forest developed under temperate and moist conditions during the middle Campanian-Maastrichtian.
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Abstract

The Lidfjellet thrust is the most prominent tectonic structure in the Lidfjellet-Řyrlandsodden fold zone, which stretches NNW-SSE along the western coast of Sřrkapp Land in Spitsbergen. This paper provides a reinterpretation of the Lidfjellet structure, with particular reference to lithostratigraphy of the autochthonous and overthrust sequences involved, and to the position of the thrust surface. Geological and palynologicalal data indicate that the sequence attributed previously to the Lower Cretaceous Helvetiafjellet Formation of the autochthonous cover represents in fact the Carboniferous (Viséan) Sergeijevfjellet Formation forming the lower part of the overthrust unit. The youngest deposits involved in tectonic structures of the Lidfjellet-Řyrlandsodden fold zone are of Upper Jurassic age.
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Abstract

Shallow−marine deposits of the Krabbedalen Formation (Kap Dalton Group) from Kap Brewster, central East Greenland, yielded rich dinoflagellate cyst and pollen− −spore assemblages. Previously, this formation yielded also rich mollusc and foraminifer age−diagnostic assemblages. A Lower Oligocene age of the Krabbedalen Formation seems to be supported by the dinoflagellate cyst assemblage analysis, while the pollen−spore as− semblages point to a wider stratigraphic age range within Oligocene–Middle Miocene.
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