| Hadexun Donghe sandstone oil field is located at the Hadexun tectonic belt ofManjiaer cancave in Shaya country, Xinjiang province. This oil field is a large sizestratigraphic and anticlinal structural trap. It has an unified WOC which is acclivefrom southeast to northwest. HD111borefild is located at northwest of HadexunDonghe sandstone oil field. Until August2011, the cumulative oil production ofreservoirs is38.8145×10~4t, the degree of reserve recovery is6.07%, and the water cutis53.0%. This borefild has basal ground water and its feature include extremely thinoil layer, bad reservoir physical property, high crude oil viscosity and complicatedfluid relationship. The development effectiveness of HD111borefild is not goodenough, and its well network is not very perfect, its vast majority of reserves is notemployed. To solve these problems, we must work out a set of reasonabledevelopment program to employ the reserves of this region on the basis of geologicalmodeling and numerical simulation. It is very significant for increasing production ofHadexun Donghe sandstone oil field.In this paper, on the basis of the actual situation and the results of reservoirgeological research of the HD111borefild, combing with the drilling, coring, corelaboratory analysis, and dynamic performance data, it is researched on geologicalmodeling and numerical simulation. And then, the development targets were proved.Finally, based on previous research, the optimal development plan was designed andoptimized. There are the following obtained results and understandings:(1) The reservoir physical property of HD111borefild is low porosity andmedium permeability. The thickness of Donghe sandstone in this section is0～27.9m,and is pinching out gradually form west to east and from south to north.(2) Structural model of HD111borefild is built on the basis of layering schemewhich has12sand beds and11interbeds. Using the method of stochastic modeling,the porosity, permeability and saturation models are established. According to theresults of this model, geological oil reserves of HD111borefild is6.74million tons，and compared with the geological oil reserves6.39million tons which calculated withvolumetric method，the error is5.48%. (3) According to the results of numerical simulation, the pressure of HD111borefild at present is48.54MPa. Through history matching, the total volume of waterbodies which include basal ground water, edge water and external numerical waterbody is17.6times of reservoir volume.(4) According to the potential analysis of the current well network, the degree ofreserves control of the current well network is very low, and developmenteffectiveness of HD111borefild is also not good enough, this can not meet the goal ofefficient development. As can be seen from the evaluation results, the natural energyof this section at present is weak, and development mode should be changed intoflood development. According to the results of the proved development targets,well-type should has tow chooses,one is that down flow well using horizontal welland production well using horizontal well,the other is that down flow well usingvertical well and production well using horizontal well. The rational length ofhorizontal section is375m, the rational well spacing is about600m, the injectorproducer distance is between525m and600m, and rational bottom hole flowingpressure of production well is about30MPa.Finally, on the basis of the above results, four development programs areproposed. Through the comparison of these four options, five-spot water floodingpattern was chosen to be the best scheme. At the end of2031, the degree of reserverecovery of best development scheme will raise12.51%and will reach27.42%.Comparing with present executing scheme, development effectiveness of HD111borefild has been significantly improved. |
PDF Full Text Request