Distribution patterns of benthic associations in offshore shelf deposits (Upper Jurassic, Central East Greenland)

Abstract

The benthic fauna of the Upper Jurassic Pernaryggen Member of Milne Land, East Greenland, occurs predominantly in shell beds separated by unfossiliferous strata. Twelve benthic associations and several assemblages dominated by suspension-feeding bivalves and brachiopods areorecognised. The vertical faunal distribution exhibits a pattern, the lateral faunal distribution, however, appears to be randomly arranged. Shell density is regarded as a function of the rate of sedimentation, whilst changes in faunal composition are thought to be due to minor fluctuations of environmental parameters and to species interactions. During diagenesis the primary distribution pattern of high and low density shell accumulations was modified by dissolution of the low density shell accumulations resulting in unfossiliferous strata.