Accumulation Distribution Characteristics And Controlling Factors Of Chang 1 Reservoir In Dongguan Area Of Dingbian Oilfield

This dissertation will be the research object of Chang 1 reservoir in Dongguan area of Dingbian Oilfield,with the data of well-log and laboratory analysis,core analysis,oil test and so on,this thesis studies accumulation distribution characteristics and its controlling factors in the study area from regional tectonic features,oil source,sand body distribution and sedimentary microfacies and reservoir characteristics.According to the lithology change and cyclic characteristics,Chang1 reservoir is divided into three reservoirs: Chang1~1 to Chang1~3.Chang1 reservoir is in the background of Western tilting single oblique structure and has nasal uplift of different development degree.In Dongguan area,chang1 sedimentary microfacies are delta front water distributary channel,the zonal distributary channel sands with the NE-SW direction.The sands development in Chang1~2 is the best in three layers of Chang1,and distributary channel sand of Chang1~2 is widely distributed.Chang1~1 and Chang1~3 are dominated by river flank.The Chang 1 reservoir in this area is medium to fine arkose and lithic arkose.The main pore configuration are intergranular pore and emposieu pore.It is held that the pore throat structure is the type of medium pore and medium-fine throat.Effect of lithogenesis,the Chang 1 sandstones is medium porosity,low permeability.The development of Interlayer has strong heterogeneity in the Chang 1 reservoirs.The oil-bearing in Chang1~1 and Chang1~2 are better than Chang1~3,Chang1~3 almost has no oil layer distribution.Study area is far away from Chang7 hydrocarbon source rocks,reservoir distribution affected by hydrocarbon source rocks;oil reservoirs distribute in nasal uplift,which control oil reservoir of Chang1,and because of its small accommodation and excess oil injection,there shows sporadic reservoir distribution in other area;Chang1 reservoir distribution form,scale,extension direction has almost the same distribution with distributary channel,show belt-like distribution;Excellent assemblages of Chang1~1 and Chang1~2 make its oil content much better than that of Chang1~3;Chang1 has strong reservoir heterogeneity,which shows in the change of development degree of interlayer and plane property changes,and heterogeneity prevent oil and gas migration,which is advantageous to the oil and gas accumulation.