Seismic-Driven Stratigraphic Interpretation and Reservoir Characterization of Deepwater Lobes: Case Study from Sadewa Deep, East Kalimantan

Deep-water stratigraphy is challenging due to rapid sedimentation changes and the abundant reworking of index fossils. Seismic data is crucial in stratigraphic interpretation, utilizing seismic characters and attributes that can infer geological interpretation. In this paper, we showed a case study from offshore East Kalimantan to highlight stratigraphic interpretation based on high-resolution biostratigraphic framework done by Morley et al. (2006) , as well as rock physics and seismic inversion study conducted to define lithology and fluid distribution.

This work was motivated by the result of Sadewa-3ST1 well, drilled in 2003. This well penetrated the main productive zone in the Sadewa Field, as well as deeper target in the Sadewa deep interval (around 13,000 - 17,000 TVDSS), however the deeper target was under explored due to limited data and lack of understanding of the depositional model. The reservoirs in the Sadewa deep interval are very-fine grained sands with high degree of thinly inter-laminated mud. The stratigraphy is located in the midway between slope-shelf break and basin floor, approximately between middle to lower slope ( Saller et al. 2004 ). Reservoir properties derived from seismic inversion shows an intra-slope basinal fan geometry with lobes developed to the northern and southern part of Sadewa field.