Exploitation of multizones by waterflooding in the Daqing oil field

The distribution of oil and water in the pay zones and the constant changes of relationship taking place among the zones in the course of development of a sandstone oil reservoir by waterflooding bear closely on its stable production and ultimate recovery. So, the result of development of an oil field depends largely on knowledge of the changing conditions and the ability to cope with them by regulatory or reconstructive measures. All the pay zones in the Daqing oil field have been clearly segregated, and on this basis, different zones in the one and same well may be flooded and produced separately. The development of the Daqing oil field has been successful, comparable to similar oil fields in the U.S. and Soviet Union in the following respects, which are disucssed: reservoir pressure maintained; wells kept flowing; stable average daily output; long, stable high- yielding period; and less water consumed than in oil fields of other countries producing oil of similar viscosity. (12 refs.)