Geological Society of London
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Large-scale magmatic pulses drive plant ecosystem dynamics

posted on 2016-06-21, 11:08 authored by David W. Jolley, Simon R. Passey, Malcolm Hole, John Millett

The 6.6 km gross thickness of the Palaeogene lava field of the Faroe Islands Basalt Group was erupted in the initial phases of North Atlantic rifting. Thin interlava sedimentary rocks yield palynofloras that vary in composition and diversity with the duration of the interlava period. Long-term trends in plant ecological succession occur within the record, each reflecting initially rapid and subsequently slowing eruption tempo. TiO2 and MgO plots derived from the basalt lava flows show corresponding fractionation trends. These link melt column processes to vegetation ecosystem dynamics via controls on eruption tempo, thermal support and substrate disturbance.