FACIES IDENTIFICATION TO EVALUATE DEPOSITIONAL MODEL AND RESERVOIR POTENTIAL OF LOWER MIDLE BANUWATI MEMBER, YANI FIELD, YANI SUB-BASIN

• Main Author: AGUSTIANA, RIZA
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/19338
• Institution: Institut Teknologi Bandung

Yani Field is located in the Yani Sub-basin or northern part of the Sunda Basin, South East Sumatra PSC Block. This field was discovered in 1983 with oil accumulation found in the bedding of conglomerates and conglomeratic sandstones reservoir of Lower Middle Banuwati Members (LMB Interval). To accelerate oil production and to added new resources, step out exploration strategy have been done to confirm exploration concept near to the facilities. <br /> <br /> <br /> This study focused on identifying facies and facies association of LMB Interval using core data, log data and seismic data. The LMB interval consists of four facies, namely massive conglomerate facies (Gm), planar cross bed conglomerate facies (Gp), planar cross bed sandstone facies (Sp), and horizontal lamination sandstone facies (Sh). Those facies are correlated to the cylindrical elektrofacies character and also correlated to the biostratigraphy data of supralitoral environment. Channel architectural element (Miall, 1985) and braided channel facies association (Selley, 2001) is interpreted for the LMB Interval. Lateral distribution of LMB reservoir is identified by using well data which is correlated to the EI seismic attributes. Low sinuosity pattern trending northwest-southeast depicted as the main trend of LMB braided channel. <br /> <br /> <br /> Different reservoir quality of each facies was identified by using routine core analysis. Planar cross bed sandstone facies has better quality rather than the other facies. Intergranular porosity becomes obvious primary porosity type which identified by thin section. Based on those data, it is mean that sedimentary texture took control of reservoir quality in this field, with evidence of sorting, pack and contact of fragments. <br /> <br /> <br /> The presence of the exploration potential in the northern field with a distance of 1.9 kilometers from Yani platform facilities is identified based on superimposed data between seismic attribute anomalies EI which represented boundary and lateral distribution of the LMB reservoir to the depth map of LMB that showing a four way dip clossure structure in the upthrown clossure fault block of Yani Field.