Study Of The Oil Reservoir Reasonable Stress Levels And The Development Policy Technical Boundaries

Gudong Production Plant of Shengli Oil Field, where Gudong Oilfield, Hongliu Oil Field and Xintan Oil Filed were dominated., is proved to have an oil-bearing area of 74.6 Km~2 with geological reserves of 28749×10~4 tons. Gudong Oilf Field, as its main oil field, which is located on the northeast section of Zhanhua depression, Jiyang Sag., is a tertiary overlaid anticline conformation, complicatedly developed with three columns of fractures and eight formations of faults by which Gudong Oil Field was divided into eight natural blocks. Ng, Ed and Es were developed in this oil field and Ng is the major oil-bearing formation.Trial production in Gudong Oil Field was commenced in 1985 and was turned into general development in May of 1986. Affusion development was started since July of 1987. Now it has been entered into ultrahigh-water-contained development phase. Due to the reason of one-off production and high-speed production, the unbalance between reserves and productions and the decrease of output have been resulted in. Although series of measures had been adopted to control water and stabilize output and some of which had taken definite effect, however, the conflict between reserves and productions still remains distinctly and the water-drive efficiency holds in a low level. There is also a problem that stratum pressure keeps on a high side.According to the characters of oil reservoir and oil production in each block of Gudong Oil Field, the article correspondingly rationalized the evaluation, by means of oil-reservoir engineering methods and numerical simulation methods, has offered some effective references to decisions making on occasion selections of the adjustments for blocks development.If the stratum pressure keeps on a low side, therefore, there would be short of energy and the output could not reach the requirement. If the stratum keeps on a high side, then more pressure and water should be affused into the layer. It would cause an increase of investments and a decrease of development benefits. The article hereby stress on how to ascertain development methods according rational pressure level in different block. Each block in Gudong Oilfield, for instance, had been estimated on rational pressure. And it had been proved that rational pressure could meet the actual demands of development by research of numerical simulation on typical block. The corresponding ascertainment of rational layer pressure, that is to say, the lower limit of layer pressure, according to different geological circumstances, different development phases and different production technology in different types of blocks, would have an remarkable significance on improvement of the general development efficiency.