Читать книгу Biogeography in the Sub-Arctic - Группа авторов - Страница 52

The Svínafellsfjall Formation in south‐eastern Iceland is approximately 0.8 Ma old and comprises lacustrine siltstone and sandstone with numerous dropstones. Plant macrofossils include Thelypteris limbosperma, Alnus cf. viridis, Vaccinium cf. uliginosum, P. viviparum, Alchemilla sp., D. octopetala, Sorbus aff. aucuparia, S. arctica tp. and S. herbacea (Figure 4). The pollen flora includes Pinus, Artemisia, Betula, Menyanthes, Thalictrum and Galium. Except for T. limbosperma, Pinus and Alnus cf. viridis, all taxa are part of the modern‐day flora of Iceland, and again the fossil flora point to forest tundra and an interglacial type of climate, which is surprising because of the frequent occurrence of dropstones in the sediments.

Figure 4 Examples of leaf imprints of vascular plants from interglacial deposits in Iceland. (a) Dryas octopetala from the Víðidalur Formation. (b) Salix herbacea from the Búlandshöfði Formation. (c) Salix arctica type from the Búlandshöfði Formation. (d) Thelypteris limbosperma from the Svínafellsfjall Formation. (e) Alnus cf. viridis from the Svínafellsfjall Formation. (f) Dryas octopetala from the Svínafellsfjall Formation. (g, h) Salix arctica type from the Svínafellsfjall Formation. (h) Salix herbacea from the Svínafellsfjall Formation. Scale bars 5 mm.

Source: Photographs kindly provided by Friðgeir Grímsson.