Study On Remaining Oil Distribution Of Block Du229 Extra-heavy Oil Reservoir In Liaohe Oilfield

Block Du229 extra-heavy oil reservoir in Liaohe Oilfield was studied as the research target. By the comprehensive co-utilization of different kinds of information such as geology , logging, producing test, history production performance, Du229 block was mainly studied from the aspects of reservoir characteristics, production feature and effect factors, water invaded region, and the remaining oil distribution model, distribution law and controlling factors. At the end, enhanced recovery direction and treating measures were proposed. The paper has the main achievements as follows:Fistly, 27 sublayers were divided based on original 6 oil sand beds. By fine reservoir description, the reservoir characteristics of Du299 block was studied from the aspects of structural feature, stratum conditions, microtectonics characteristics, interbedded stratum, formation fluid, and reserves was recounted..Secondly, the rheological behaviors of the super heavy oil were investigated from three aspects which were the relationship between the super heavy oil and temperature, the relationship between the super heavy oil viscosity and temperature , the inversion temperature of Newtonian fluid of the super heavy oil. Non-Darcy flow pattern of the super heavy oil steam stimulation was established based on the research of rheological behavior. Then, the extract law and production characteristics of the super heavy oil steam huff and puff in Du229 block was analized by production datum.The factors that affec supper heavy oil reservoir steam stimulation development were analyzed from four aspects of reservoir geologic conditions, steam injection parameters, steam breakthrough and casing wear.Thirdly, by con-utilaziont of many methods such as exploitation and geology, dynamic producing process monitoring, water invasion behavior, core analyis and numerical simulation, 10 kinds of reservoir scale remaining oil distribution pattern in the steam huff and puff super heavy crude oil reservoir was put forward. Also, remainling oil distribution in the sand bed scale and sublayer scale were pointed out.Fourthly, Microcosmic displacement experiment was conducted for hot water driving in 100℃and 120℃. and steam drive at 170℃condition. Microcosmic remaining oil distribution characteristics were summarized. Remaining oil microcosmic distribution by steam drive at 170℃is different from that at 100℃, 120℃hot water driving. After the steam drive, there are three types of remaining oil distribute regular pattern, whic is impacted by many affecting factors like pore configuration, wettability and interfacial tension.Fifthly, buildup and affect factors of super heavy oil distribution were analyzed from four aspects of microtecnotics, deposit microfacies, reservoir nonhomogeneity and developing techniques. It is pointed out that crude oil viscosity, formation physical properties difference, sand body rhythm and performation intervals are mainly factors controlling remaining oil distribution. Steam overlapping acting is the most important cause influencing super heavy remaining oil distribution.Finally, the quantity of remaining oil in each oil layer in Du229 bolck was calculated and 8 kinds of tapping measures of remaining oil were proposed, using petroleum reservoir engineering method. The selection standard and deployment scheme of infill horizontal wells was proposed and production effects of infill horizontal wells were analyzed. At the same time, using numerical simulation, the well spacing pattern, horizontal length, vertical distance between injecting and producing wells were optimized for the dual horizontal wells in the XingⅢ2 oil sand formation changed to SAGD development style. The study outcome has been applied in remaining oil digging on the spot, good results been achieved.