Study On Oil-water Relationship Of Ordovician Reservoir In Block 6 And 7 Of Tahe Oilfield

The Ordovician reservoir in Tahe oilfield is made up of fracture-cavity unit with different pressure systems and oil-water relationship, The existing oil-water relationship models hasn't reflected completely the characteristic of reservoir. Based on the previous geology and development performance, emphases on Block 6 and 7 of Tahe oilfield, combine of Drilling event, testing data ,seismology, logging etc,it was analysed that includes the layer model,distributing of liquids and water performance with the basic unit of fracture-cavity unit, it has been studied in this thesis that the driving energy of the reservoir and the injecting water performance. The oil-water relationship concept models have been established that can be used to interpret soundly development performance in typical fracture-cavity units, which can predict the developing strategy by theory.And obtain some important conclusions.1. It's that cave and fracture constitute the fracture-cavity unit. The concept model of fracture-cavity unit can be descript by one or more large pipeline shape cavity systems formed in a periods or several different periods, communicated by nature and acidizing-fracturing fracture in Ordovician tight carbonate rock.2. According to the analysis of Reservoir-forming mechanism, the depth of oil-water Interface is calculable using original formation pressure of wells. The fracture-cavity unit interior various wells not necessarily have unify the water-body,but it is possibility its original oil-water Interface was accordant. The pipeline shape reservoir characteristic has decided the water-body upward invasion by reservoir edge primarily.3. According to oil-water output change after a well began to produce water, it can be classified product water character into slow, fast and intermittent product water type. In multi-wells fracture-cavity unit, not every well water production keeps to the law that consistent edge and bottom water invasion. There may be more than one water-body in a fracture-cavity unit.Through argumentation, it's considered that compartmental oil driving water is principal mechanism in the finite water body with feebleness energy. Water may invade into reservoir along the portrait fracture or cave corridors if there is a large water body under the oil-body.4. While increasing energy of fracture-cavity unit by carring through the water injection, the oil-water Interface would be heighten, The principal driving energy of producing water is energy of ompartmental oil driving water in the process of water injection.5. The oil-water relationship concept models can be descript one or more no affiliation large water-body existed in bottom or edge of fracture-cavity systems in a complicated fracture-cavity units layer systems ,there may be some compartmental oil-body in fracture-cavity systems by water-body. The energy of ompartmental oil driving water or a large water-body under the oil-body maybe the principal mechanism of oil-well producing water.