Facies distribution of Early Cambrian molluscs in Estonia

The helcionelloid mollusc Anabarella was recently found from the Kestla Member of the Lontova Formation in the Vanamõisa F-149 core at a depth of 123 m. The appearance of Early Cambrian molluscs Aldanella and Anabarella in Estonia was connected with the maximum expansion of the Cambrian palaeobasin on the East European Platform. In the Lontova Stage the molluscs occurred in the facies deposited in quiet hydrodynamic conditions which were typical of the maximum marine transgression characterized by extensive clay accumulation far from the coast.