Geocellular Modelling of a Naturally Fractured Carbonate in the Song Hong Basin, Vietnam

Abstract

Building geocellular models in fractured reservoirs is a very challenging task which involves not only capturing the matrix properties but also the distribution of different kind of fractures and their properties in the reservoir. The problem becomes even more complex when limited information is available especially in new discoveries. This paper presents in detail the modeling methodology applied in a recently discovered field in the northeastern edge of the Song Hong Basin, offshore Vietnam. Only two wells have been drilled: the first well, after four side tracks due to drilling difficulties in the overlying Oligocene shales, penetrated oil bearing Pre-Tertiary carbonates. As a result of the drill bit dropping 3 m at the top of the Carbonate, and the well experiencing losses, the well was able to proceed with a well test that produced a natural flow of 4,858 bbls/d of 39 API oil. The second exploration well was drilled on the Eastern side of the field penetrating 400 m section of Pre-Tertiary carbonates with a production test in natural flow rate of 3,401 bbls/d of oil after acidizing.