Research Of Main Control Factors Of Oil Accumulation In Gaosan Formation In Xingbei Region, Daqing Placanticline

Gaosan formation in Xingbei Region of Daqing placanticline was another new oil exploration area, in order to study oil distribution features of Gaosan formation in Xingbei Region, Daqing placanticline, and guide oil exploration better, based on dissection of oil reservoir and analysis of oil-water distribution law, through analysis of relation between oil distribution and reservoir conditions, the main control factors and types of oil accumulation in Gaosan formation of Xingbei Region, Daqing placanticline was studied and advantageous zone of oil accumulation was forecasted.This paper acquires some main results as following:(1)oil reservoirs in Gaosan formation of Xingbei Region can be divided into 6 types as fault-anticline reservoir, fault-nose reservoir, fault sealing reservoir, structure-lithology reservoir, fault-lithology reservoir and lithology reservoir.(2)oil reservoirs in Gaosan formation of Xingbei Region are distributed sporadically in horizon plane, with feature of “west area is better and east area is worse”, oil mainly distributes in sandbody formations above little layer G34-5 vertically.(3)oil accumulation in Gaosan formation of Xingbei Region is mainly controlled by 5 factors: ①hydrocarbon resource rock control oil distribution on horizon as “west area is better and east area is worse”, ②oil-gas migration direction and routes control oil-gas accumulation area; ③transporting fault lift and upper reservoir development result in that oil-gas mainly distribute in shallow layers; ④positive structures around intensive fault zones are main areas of oil accumulation; ⑤lateral sealing ability of sealing faults control the degree of oil accumulation.(4)two types of oil accumulation in Gaosan formation of Xingbei Region are settled: ①oil accumulation type of oil-gas migrating along strike of fault(intensive zones) and sealed by fault in northwest slope area; ②oil accumulation type of oil-gas migrating along sandbodies and sealed by adverse fault in southwest slope area.(5)6 advantageous areas of oil accumulation are selected in Gaosan formation of Xingbei Region, including 1 typeⅠ,3 type Ⅱ and 2 type Ⅲ. Type Ⅰ advantageous areas are located at west of Xing 69 well in central anticline zone; Type Ⅱ advantageous areas are located at east of Sa 69-x3 well in northwest slope area, north of Xing 5-3-b040 well in southwest slope area and north of Xing 4-3-g23 well in west of central anticline zone; Type Ⅲ advantageous areas are located at east and west of Xingfu 70-1 well in central anticline zone.