Lower Limits of Physical Properties and the Controlling Factors of Effective Reservoirs in Jianquanzi Member of Baiyanghe Formation of Palaeogene in Laojunmiao Tectonic Zone,Jiuxi Basin in China

Based on the comprehensive application of oil production test,mercury injection data and physical properties,the lower properties limits of the effective reservoir rocks were determined in different intervals of Jianquanzi... [ view full abstract ]

Based on the comprehensive application of oil production test,mercury injection data and physical properties,the lower properties limits of the effective reservoir rocks were determined in different intervals of Jianquanzi member of Baiyanghe formation in Laojunmiao tectonic zone by applying distribution function curve method,production text methods and the lowest effective pore throat radius method,and the influence factors were analyzed.On this basis, regarding the porosity and permeability as comparison parameters, this paper analyzed the effects of lithology,sedimentary facies,diagenetic stage and formation pressure on the formation of effective reservoir rocks.The results show that the limits(porosity and permeability)decline with the increase of burial depth,and there is a function relationship between them.The effective reservoir was mainly develoded in the underwater distributary chanel and mouth bar of the deltaic front and channel,braid bar of deltaic plain. On the whole favorable sedimentary facies is the key factor controlling the development of effective reservoirs,while diagenesis and formation pressure also affect reservoir quality to a certain extent.The diagenesis stage is different in different intervals and the reservoirs in favorable sedimentary facies protected by overpressure are easily to be good effective reservoirs under pressure solution.