<![CDATA[ABSTRAKSebanyak 15 sampel yang terdiri dari batupasir dengan semen karbonat dalam berbagai ukuran butir dari Formasi Bentang di daerah Babakan Kabupaten Pangandaran dianalisis pengamatan mikroskopis dan penentuan umur berdasarkan kumpulan nannofosil gampingan. Sisipan batulempung sesekali muncul di antara batupasir di bagian selatan lokasi pengambilan sampel. Kumpulan nannofosil gampingan umumnya banyak hingga sedikit dan preservation nannofosil terawetkan sedang - baik. Kerangka biostratigrafi terdiri dari 5 (lima) peristiwa Zonal berdasarkan kemunculan 21 spesies nannofosil gampingan. Lima spesies datum nannofosil yaitu terdiri dari kemunculan akhir Coccolithus miopelagicus (Zona 10.613 Ma atau NN8); kemunculan awal Discoaster hamatus (10,541 Ma) dan kemunculan akhir Discoaster hamatus (9.560 Ma) atau Zona NN9-NN10; kemunculan awal Discoaster berggrenii (NN11/NN10); dan interval atas Reticulofenestra kecil (7.167 Ma atau NN11 Zone). Lebih khusus lagi, interval umur pada Formasi Bentang daerah Pangandaran berkorelasi pada Miosen Akhir yaitu dari Zona NN8 hingga Zona NN11. Dominasi Reticulofenestra kecil di Zona NN11 menunjukkan korelasi positif dengan kelimpahan produktivitas coccolith di Formasi Bentang. Kata Kunci: Formasi Bentang, Nannofosil Gampingan, Miosen Akhir, Pangandaran ABSTRACTA total of 15 samples composed of sandstones with carbonate cement in various grain sizes from Bentang Formation in the Babakan area of Pangandaran regency were analyzed for microscopic observation and age determination based on the calcareous nannofossil assemblages. Claystone inserts occasionally appear between these sandstones in the southern part of the sampling location. The calcareous nannofossils assemblages are generally common to few and preservation of sample is moderate to good. The biostratigraphic framework consist of 5 (five) Zonal events based on the occurrences of 21 species of calcareous nannofossil. Five nannofossil datum species are consist of last occurrence of Coccolithus miopelagicus (10.613 Ma or NN8 Zone); first occurrence Discoaster hamatus (10.541 Ma) and last occurrence of Discoaster hamatus (9.560 Ma) or NN9-NN10 Zone; first occurrence of Discoaster berggrenii (NN11/NN10); and top of small Reticulofenestra interval (7.167 Ma or NN11 Zone). More specifically, an age interval at Bentang Formation of Pangandaran area was correlated for the Late Miocene from NN8 Zone to NN11 Zone. The dominance of small Reticulofenestra at NN11 Zone shows a positive correlation with abundance of coccolith productivity in Bentang Formation. Keywords : Bentang Formation, Calcareous Nannofosils, Late Miocene, Pangandaran]]>
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