Ichnofabrics and their environmental interpretation from Tianziling Formation （Upper Devonian） of northern Guangdong

Ichnofabric is sedimentary rock fabric resulti ng from biogenic reworking and is the product of the interaction of physical and biological processes. Four ichnofabrics have been found in carbonates from Tianzi ling Formation (Upper Devonian) of northern Guangdong, including:Planolites montanus ichnofabric reflecting limited platform or obturate bay en vironments; Thalassinoides-Planolites ichnofabric formed in platform downtidal low energy zone; Skolithos ichnofabric presered in upper and middle tidalflat sediments; Thalassinoides ichnofabric controlled by firmground subtrate. The firmground substrate trace fossil Thalassinoides sp. demarcates discontinuity surface that reflect pauses in sedimentation, generally accompanied by submarine erosion.