Stratigraphic applications of substrate-specific ichnofacies: delineating discontinuities in the rock record

Abstract: Trace fossils represent both sedimentological and palaeontological entities, providing a unique blending of potential environmental indicators in the rock record. Trace fossils and trace fossil suites can be employed effectively to aid in the recognition of various discontinuity types and to assist in their genetic interpretation. Ichnology may be employed to resolve surfaces of stratigraphic significance in two main ways: (1) through the identification of discontinuities using substrate-controlled ichnofacies (the firmground Glossifungites ichnofacies, thehardground Trypanites ichnofacies and the woodground Teredolites ichnofacies); and (2) through careful analysis of trace fossils in vertical (soft-ground) successions (analogous to facies successions). Integrating the data derived from substrate-controlled ichnofacies (so-called omission suites) w h palaeoecological data from vertically and laterally juxtaposed softground ichnological successions greatly enhances the recognition and interpretation of a wide variety of stratigraphically significant surfaces. When this is coupled with conventional sedimentary facies analysis and sequence stratigra-phy, a powerful approach to the interpretation of the rock record is generated. Trace fossil assemblages can be employed effec