The organic assemblages (pollen, spores, dinoflagellate cysts, plant debris) extracted from Oligocene and upper Miocene sediments of the Hovgård Ridge (Ocean Drilling Program Site 908) are dominantly of terrestrial origin. With its present position in the middle of the Fram Strait (Greenland Sea), an obvious source for these terrestrial fossils is lacking. However, they are in full consistency with the tectonic model for the ridge's origin as a sliver rifted from the Svalbard Platform since anomaly 13 time. The dominance of pollen and plant tissue fragments (often >100 µm) and the low proportion of dinoflagellate cysts (usually <20%) indicate relatively short distances to a forested lowland with prolific humic productivity. The pollen flora in the Hovgård Ridge sediments present a unique glimpse into previously unknown vegetation in high northern latitudes during middle Oligocene and late Miocene times. The pollen indicates forests of conifers related to Pinus, Picea, Tsuga, and Taxodium, with a minor element of angiosperms but relatively common ferns. This is different from the well-known Paleocene-Eocene floras on adjacent Spitsbergen that were also rich in conifers but had a richer and more diverse angiosperm element and lacked Tsuga relatives. It is a surprising observation that there is no change reflected in the pollen from the Oligocene to the upper Miocene.
Date of initial receipt: 5 July 1995
Date of acceptance: 21 December 1995
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