Ichnology of the Cambrian Ociesęki Sandstone Formation (Holy Cross Mountains, Poland)

Abstract

Quartz arenites and wackes with intercalations of silty shales of the Ociesęki Formation were analysed in small outcrops and one core. The succession contains about forty-three ichnogenera and seventy-four ichnospe- cies, among which thirty-three ichnogenera and fifty-three ichnospecies are described by present author. The formation belongs to the Schmidtiellus-Holmia Superzone and to the Protolenus-Issafeniella Zone. Most strata are totally bioturbated. The diverse and numerous trace fossils represent the Cruziana ichnofacies in the lower part of the formation and the Skolithos ichnofacies in the upper part. A few possibly new ichnospecies of different ichnogenera have been described in open nomenclature. Sedimentary structures and trace fossil assemblages indicate that the older part of this formation was deposited on the upper offshore to lower shoreface, while its younger part was deposited on the lower to middle shoreface, where storm episodes were the main factor controlling sedimentation and the activity of benthos. The trace fossil associations studied are similar to those from the lower Cambrian in many places around the world. The ichnoassociations from the Polish part of the East European Platform and from Sweden, which represent the Baltica palaeocontinent, display the closest similarity.