Tengiz oilfield: geological model based on hydrodynamic data

The Tengiz oilfield, in the Precaspian Basin, western Kazakhstan, was discovered in 1981, but the size of the field and its large oil reserves were not fully estimated until many years later. Presently, it is known that the oilfield stretches over an area of almost 400 km2 but the thickness of the productive zone was not recognized untill recently. Formation pressure distribution in the Tengiz carbonate reservoir allows definition of the position of the oil–water contact. Reservoir characterization and hydrodynamic data are the basis for a dynamic model of the Tengiz oil accumulation which reflects the reservoir architecture, filling history of the reservoir and distribution of productive zones.