FACIES ANALISYS AND RESERVOIR CHARACTERIZATION OF CARBONATE BATURAJA FORMATION PONDOK TENGAH STRUCTURE NORTH WEST JAVA BASIN

• Main Author: HARYANTO, SUGENG
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/69600
• Institution: Institut Teknologi Bandung

This research was performed in an attempt to gain a good understanding on carbonate reservoir characteristics of Baturaja Formation in Pondok Tengah, West Java. Data from some samples of sidewall core and cuttings in PDT structure reveal a variation of reservoir characteristics, e.g. facies, porosity, texture and fluid saturation, which affected the reservoir distribution. In order to solve this problem a petrological study was carried out, which includes sidewall core description, petrographic analysis, formation image (FMI) interpretation and log analysis. The lithological study ends up with an identification of forth carbonate facies named Planktic foram bioclastic wackestone, Large benthic foram bioclastic packstone to wackestone, Red algae – benthic foram bioclastic packstone to wackestone, and Coral-algal bioclastic packstone to wackestone. These facies were classified into three groups: Reefal, Lagoonal and Open Marine facies groups. Base on PDT-1 well data exhibit some differences of diagenetic products in each sample swc and cutting, which were controlled by facies, shape and original platform, diagenetic processes and also environment. These dissimilarities resulted in variation of reservoir quality, to be applied in calculation of hydrocarbon saturation. Carbonate deposition of Baturaja Formation in PDT domain intrate by phase-1 of transgression and regression coral-reefal unit on Ramp Platform Morphology. Next phase characterized by agradation consists of maounded reefal with mixing to meteoric diagenetic zone. Agrading system mounded and sigmoid of Red-algal / Benthic foram bioclastic packstone marked the phase-3 with porous carbonate which developed in fresh water / vadoze environment. Phase-4 characterized by prograding Large benthic foram bioclastic packstone developed in fresh water / vadoze zone and carbonate deposition ended by phase-5 which consists of Planktonic foram bioclastic wackestone which indicate an open marine system. Distribution of carbonate reservoir from seismic and well interpretation is to the south with sigmoid / progradation from seismic event and shallowing up facies from PDT-1.