Ichnofabric for stratigraphic analysis: an outcrop study in Samarinda Area, Kutai Basin, Indonesia

The identification of demarcation surfaces of ichnofabric criteria is introduced here with reference to outcrops study in Samarinda Area, Kutai Basin Indonesia. Accordingly, the ichnofabric criteria such as ichnotaxa, tiering styles, BI (bioturbation index), diversity, burrow diameter, and penetration depth are gathered, processed, analyzed. Consequently, the three ichnofabric criteria include (1) the changes from section composed predominantly of ichnofossil to another one that absent of ichnofossil or vice versa, (2) the changes of multiple tiering styles to single tiering styles or vice versa, (3) the changes of internal tiering styles within of the single tiering style section are resulted. Moreover, those criteria are representative of three demarcation surfaces that proposed.