The Influence Of Water Injection Development On The Heterogeneity Of Extra Low Permeability Reservoir

Study of reservoir heterogeneity is oil and gas field exploration and development of one important basic work of geological research.Take The Tang Jiachuan wellblock in the Jian Yucha oilfield based on the ordos basin as the research object.In order to solve the mid waterflood development in the study area,for the problems to deepen the study of reservoir heterogeneity.This research mainly through the qualitative and quantitative methods,and respectively in view of the reservoir layer upon layer and interlayer and plane heterogeneity in three aspects: the research step by step,and the inner layers of the objective interval,interlayer and plane heterogeneity,respectively,to make comprehensive evaluation.Through the study of reservoir heterogeneity,the permeability of the study area in Chang 61 and Chang 62 rhythm is more complex,all kinds of rhythms that appear,reverse rhythm in all rhythm is the most beneficial to the production and the water injection development;Attributed to the sandwich layer,and the distribution of interlayer is not stable,abundant of interlining makes the intraformational heterogeneity of Chang 61 and Chang 62 are strong;Through qualitative and quantitative research methods,to determine the intraformational heterogeneity of Chang 61 and Chang 62 are of strong heterogeneity,and Chang 62 degree of intraformational heterogeneity stronger than in Chang 61.Through to characterize interlayer heterogeneity parameters and the degree of permeability heterogeneity research,determine the Chang 61 and Chang 62 have strong interlayer heterogeneity,and 61 is slightly weak interlayer heterogeneity in Chang 62;For long two small layers within Chang 62,Chang 62-1 small layer heterogeneity is slightly better than a small Chang 62-2 layer,and on the whole Chang 62 interlayer heterogeneity is strong.Through for sand body geometry,continuity and connectivity and plane heterogeneity study found that the sand bodies in the area of a poor continuity and connectivity,and each small layer has a certain plane heterogeneity,Chang 62 two small plane heterogeneity within the layer than the three small layers in Chang 61;Chang 61-1 and 61-2 plane permeability heterogeneity degree is not high,Chang 61-3,Chang 62-1,Chang 62-2 layer three small plane degree of permeability heterogeneity is strong.Through the interlayer and the influence of sand body connectivity for waterflood development,the study found interlining for reservoir waterflood development in the study area layer has a significant impact,in thin and extended mezzanine appears more not long development blocks,sandwich too much is bad condition of water flooding development,and sandwich layer effects on water flooding development effect is very obvious,the thickness of the interlayer is also has a certain influence,but much weaker than the degree of interlayer.Study the sand body connectivity in general,but sand body connectivity is still decided to the first condition of water flooding development effect is good or bad,in the water injection development,should not only consider the injection Wells and production Wells in the exploited horizon of sand body are connected,must determine whether the perforation position of water injection and production,is both connectivity to the influence of water injection development important advantages,not a single one of these conditions can be dispensed with.