MASS MORTALITIES ON AN IRISH SILURIAN SEA-FLOOR

Recurrent deep-water benthic communities, dominated by diverse tabulat e corals, colonized soft substrates during the late Llandovery transgr ession in western Ireland. A. number of autochthonous shelly assemblag es dominated by brachiopods, corals and crinoids occur in the upper pa rts of the Kilbride Formation; the highest and most distal levels are dominated by in situ tabulate corals that are mantled by a thin layer of volcanic ash. Most of the coral colonies could cope with limited se dimentation: growth ceased after the volcaniclastic surge. This catast rophic mode of preservation permits an accurate analysis of an early s tage of community development in deep-water benthos on a soft Llandove ry seabed, periodically swept by volcaniclastic debris. The Kilbride f aunas have implications for the palaeoenvironments and taphonomy of de ep-water marine faunas associated with areas of active volcanism.