Autocyclic development of Oxfordian sponge-microbial bioherms from Central and Southern Poland

Abstract

A study of Upper Jurassic sponge-microbial bioherms in Poland allow to recognise successive changes in bioherm facies. No-time related character of these changes proved for different bioherms excludes external mechanism of facies development. The existance of ecological co-dependence etween sponge and cynaobacteria may be treated as main reason of facies changes.