AGE AND DEPOSITIONAL ENVIRONMENT OF WALAT FORMATION BASED ON PALYNOLOGICAL ANALYSIS IN SUKABUMI REGENCY, WEST JAVA, INDONESIA
Journal: Pakistan Journal of Geology (PJG)
Author: Rizki Satria Rachman, Winantris, Budi Muljana
This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Walat Formation is equivalent to Bayah Formation. This formation is the beginning of Bogor basin deposition. In this case, age and environment of this formation have been analyzed by previous researchers, but the results of age and environment interpretations have different ranges, especially from itspalynological aspect which until now Walat Formation is rarely analyzed using this aspect. This research was conducted to identify the age and depositional environment of Walat Formation in Sukabumi region by using pollen and spores to confirm different interpretations of previous studies. Measure sectionwas carried out in sampling and chemical treatment method was carried out to see palynomorph content in the rock. Furthermore, data analysis wascarried out with range of interval zones and pollen grouping based on their environment.
The results show that Walat Formation has Late Eocene age based on the interval zone between first occurrence of Verrucatosporites usmensis andMeyeripollis naharkotensis, and the last occurence of Proxapertites operculatus, Proxapertites cursus, and Cicatricosisporites eocenicus. Walat Formation hasfluvial depositional environment characterized by the dominance of Proxapertites operculatus and Proxapertites cursus. The results of this study confirm that the Walat Formation has an Eocene age and a fluvial depositional environment from a palinological aspect.