Calculation Of Stratified Stress And Its Application In WeiXing Oilfield

The Weixing oilfield is located in the northwestern part of the Sanzhao sag,west to Taipingtun Oilfield in Daqing placanticline,and the Songfangtun oilfield in the south of Sanzhao sag.The oil reservoir of the Weixing oilfield is facing the key period of increasing the production,and establishing a fine pre-pressure assessment method has become an important task for the development of oilfield.On Putaohua oil reservoir in the Weixing oilfield,the paper focuses on the continuous stress profile calculation,stress plane distribution,effective partition stress division and stress calculation results to research application and corresponding suggestions in fracturing channeling.First,using the optimized inversion technology system,rock mechanics parameters and geostress methods are calculated through conventional logging data.Density logging data construction and transverse wave construction based on XMAC and other special logging are protect the completeness of basic data.Combined with the data of oil test and fracturing well data in the block,by means of analysis and inversion,establish a longitudinal geostress and horizontal geostress calculation model is suitable for Weixing oilfield.Second,summarize the stress distribution in this area,based on the 418 Well geostress calculation results in the Putaohua reservoir.The minimum horizontal stress distribution range is 16.9MPa-27.3MPa,the fracture pressure gradient distribution range is 0.015MPa/m-0.0211MPa/m.Third,based on the analysis of the geostress,and combined with the previous fracturing conclusion,to establish a method for divide the interlayer with stress in Weixing oilfield.Based on the analysis of geostress,establish the effective co MPartment identification chart,such as the interlayer stress difference and interlayer thickness chart,and the interlayer stress difference and interlayer quality parameter chart,the chart compliance rate reaches 93.8%.Use of data from 11 fracturing wells for fracturing recommendations and validation effect interlayer chart,the chart compliance rate reaches 90.9%,meet the demands of site construction.Fourth,Combining the status of fracturing technology,give suggestions and measures to optimize fracturing design and improve the success rate of fracturing,through the fracturing displacement,The unit thickness silt carrying capacity,proppant and Optimized fracturing process ect.The paper studies and establishes a suitable calculation method for geostress profiles for Weixing oilfield,and based on that,study feasibility of fracturing stress layer,establish effective method for divide the interlayer,It achieved the guidance of oilfield fracturing design,improved the effect of fracturing,and enhanced oil recovery.