Publications

S field has unique geological conditions, with a depth of maturity around 800 meters based on geochemical analysis and classified as the shallowest in the Kutai Basin compared to other fields of around 4000 meters. This is caused by this field's geological conditions, which are influenced by the tectonic gravitational force from the north and the lifting of the middle Miocene formation from below. The study aims to have better understanding on the petroleum system using the ∆ Log R to analyse the source rock, to be integrated with the Cyclostratigraphy-INPEFA log to discover which cyclic deposition trend has the higher TOC (total organic carbon) accumulation. Determining the potential source rock with the rich TOC would help the finding of a new prospect reservoir for conventional or unconventional development. ∆ Log R is a practical method for predicting TOC and depth, applied in many fields with success stories. The research focuses on TOC prediction on a delta plain environment with abundant coal source rock using sonic, density, and neutron logs as porosity logs. Because most of the Organic Content is found in Non-Reservoir Rocks, Reservoir Rocks needs to eliminate Log-Gamma Ray as a lithological interpretation. Mature Organic Rocks with a high TOC value and excellent porosity will show high resistivity; this is because Kerogen, which is dominant in shale, validates this TOC prediction for geochemical analysis. Cyclostratigraphy-INPEFA log is generated from a particular formula based on cyclic deposition concept that refers to the orbital change that affects earth insolation. The phenomena cause the sea-level change (eustasy). When the sea level drops (cooling phase), the coarse sediment will be deposited., Whereas the finer sediment will be deposited when the sea-level rises (warming phase). This study shows that predicted TOC accumulation is much higher in the warming phase.