Research On The Control Action Of Fracture Toremaining Oil And Injection-production Relationship

According to the study of reservoir remaining oil distribution features in daqing oil field north two west block, found that remaining oil enrichment, and fracture development situation has a good corresponding relation.Therefor make Saertu reservoir, Putaohua reservoir and Gaotaizi reservoir as purpose reservoir, combined with the seismic data, tectonic sedimentary background, and according to the fracture development in the study area, to determine the control action of fracture to the remaining oil distribution; In order to realize the safety of the remaining oil mining within each block, adjustment of water injection and liquid withdrawal rate should be made on the basis of existing injection-production relationship, so according to the data, water flooding of nissan, judgment of injection-production relations in each block in the study area; Comprehensive utilization of well logging data and the regional stress data,calculate the cross section can withstand pressure difference, to determine the control action of fracture to the injection-production relationship. The mainly understanding include the following:1,The enrichment of remaining oil at the study area in the plane around the fracture, the main enrichment in the cross parts of the fracture, the end of fault and the lower plate at reverse fault;In vertical enrichment is at Saertu and Pitaohua 1 in shallow reservoir, with the increase of depth, its oil content variation of each oil layer,Gaotaizi 2 reservoir group is in the majority with oil-water layer.2, The control factors of remaining oil distribution at the study area mainly include:(1)fracture fragment growth transformation zone is the main place to remaining oil enrichment;(2) under the control of the sealing ability to reverse faulting footwall residual oil is relative enrichment area;(3) parts provide favorable reservoir space for residual oil sand body development, also is the place of enrichment of remaining oil is relatively;(4) the distribution of remaining oil at the same time is controlled by the original oil relative enrichment area.3, The department fracture cross section pressure boundary at the study area is mainly with the increase of depth, confined boundary increases gradually, the fault section by S1 reservoir group increased an average of 2.4 MPa to P2 reservoir group average of 16.9 MPa;For the same reservoir groups, between different fault and different locations of the same fault confined boundaries without too big change, are basically identical.4, Individual fault block at the study area has the balance of the formation pressure close to the original formation pressure, can maintain current injection-production plan, the balance of most of the fault-block formation slightly larger than the original formation pressure, these fault-blocks need to decrease the injection pressure and water injection fluid volume, in order to reduce the balance formation pressure.