Study On Adjustment Strategy Of Waterflood Development In Songshunlin&Xinyao Area Of Nanniwan Oilfield

Songshunlin&Xinyao Well Field is located in the middle of the first structure unit of northern shaanxislope in Ordos Basin. This field is in the mid-anaphasc development at presen. The total water cut islow,but water injection is too late and well pattern is not perfect,lower recovery factor and low explorespeed are the main problems this area facing. For excavating the development potential of the oil reservoirand enhancing recovery, it should be on the basic of re-recognizing the geological characteristics of thereservoir,the reservoir engineering evaluation and the study of residual oil to adjustment and perfectinjection-production system to reach scientific,reasonable and efficient development,it is every important toimprove the oil exploration.This text makes triassical Chang4+5,Chang6reservoir group of Songshunlin&Xinyao Well Field asthe main research objects.Using geological,drilling, analysis and test date, basing on the petroleum geology,sedimentary petrology and geophysics,restudies the geological features of this oil-field that mainly containssedimentary facies,reservoir and structural feature and other aspects.The results show that Chang6reservoirsedimentary facies of YanChang group belongs to delta front sub-facies sedimentary of delta sedimentarysystem and Chang4+5belongs to delta plain subfacies deposition.Reservoir physical property of this area ispoor and it is mainly low-porosity and low-permeability reservoirs. This test study reservoir from aspects ofdevelopment effect, well-pattern system and layer series of development,and they are the innovative pointsof this test,which lay a foundation for the establishment of next step adjustment scheme.Reveal therelationship among the geological characteristics and oil well productivity by geological research andanalysis.Using reservoir engineering method, development technology analysis to evaluate reservoirengineering,which contains water injection efficiency evaluation,layer series of development and theproduced.The research shows that well pattern is not perfect and the produced is too low in this area. Inorder to improve the waterflooding effect,we should relevant formulating adjustment plan to provideevidence for next exploration.According to the analysis,we holds that encrypt present well pattern and use anti-nine-spot pattern canimprove injection-production pattern and increase recovery.