Abstract
The fluvial deltaic VICO's Reservoirs are located in the eastern part of Kutai Basin, Indonesia, being Badak one of their biggest and most prolific Fields that has been producing gas for more than 35 years.
Badak, the first gas field discovered in the Basin, presents the concentrations of hydrocarbon in fluvial sediments, mainly in channels and bars deposits. These bodies are distributed through a vertical interval of thousands feet over various areas of the structure. At present, we face the challenge of developing the remaining gas reserves in these low permeability deep reservoirs. These reservoirs locally known as G and H levels are at depths between 11,000ft to 13,000ft.
During last couples of years considerable efforts have been done on developing fluvial facies model based on sedimentary environment and core data. The key factor, for better understanding the potential areas was an integrated 3D Model including also a detailed petrophysical analysis.
Based on core data cut-off values of porosity, permeability and water saturation were calculated and used for selection of the best well candidates, with the higher flow rates. The same cut-off values were applied in the 3D model in order to identify and characterize the main productive areas with high storage and flow capacity. The 3D model helped to understand the areal and vertical distribution of these petrophysical properties as well as porosity and water saturation.
As a result, confident locations for development of these low permeability reservoirs can be presented in order to increase the current recovery factor. Right applications of a reliable 3D model allows to identify of best areas and potential reservoir characteristics from limited quantity of data, obtainable from conventional cores and well logs to maximize the success of the project. Drilling in these reservoirs already contributed with 30 MMCFD of gas equivalent to 30% of field production.
