The potential of ichnofossil for the interpretation of depositional environment conditions: an example from outcrop studies in Samarinda, Kutai Basin, East Kalimantan

Sedimentological research in the Kutai Basin related to deltaic deposit has been studied since 1970s which lithofacies has been employed as central parameter. However, that has been contrary the fact that ichnofossil has been still paid regardless of fruitful parameter and used solely as attribute of depositional environment analysis by previous workers although they have to record it. This paper will establish the potential of ichnofossil data to explain the meaning of the cyclical and variability of fluvial influx and marine process based on outcrops studies in Kesejahteraan and Melati Roads, Samarinda City. The use of ichnofossil characteristics (e.g., bioturbation index, ichnodiversity, burrow diameter, burrow lining and penetration depth) as a proxy for the ascertaining the environmental conditions. The significant finding is that environment regularly might have been intruded by various intensities of fluvial influx, thereby fluctuating environmental conditions such as salinity, water turbidity, oxygenation, sediment stability. That of environment did not compel the depositional environment is changing but manifested the short lived construction in the delta formation. The proposal of various deltaic processes is rather more conjectural in spite of the fact that limited ichnofossil data can make a difference in understanding. The enforcement of ichnological analysis is required to accomplish the rigorous interpretation