Compaction-related style of Rusophycus preservation from Furongian (Upper Cambrian) of Holy Cross Mountains (Poland)

Abstract

In general, the trace fossil Rusophycus, preserved as a concave-upward structure on the top of a bed, is considered to be a fossilized marking, made by a trace maker. The structures described from the Cambrian (Furongian) of central Poland are genetically related to Rusophycus. However, despite their occurrence on the tops of beds, they are not fossilized traces, but compaction-related features, resulting from differential sandstone and mudstone compaction with possible mediation by organic-rich, heterolithic sediments. The preservation of these structures probably was influenced by biofilms or biomats.