Internal Heterogeneity Analysis Of The Glutenite Reservoir Y227 District In North Dongying Sag

Y227 block locates in Yanjia Oilfield,and its huge thickness,vague internal formation division and strong heterogeneity of Es4 formation highly confine the reservoir expolration and exploitation.Besides,the large well distance and little number of vertical wells makes it difficult for conventional reservoir analysis method to be used in the study area.Basing on analysis of type and distribution of lithofacies in the study area,build the reservoir model combining well data and seismic data,and use the model to evaluate the internal heterogeneity of the glutenite reservoir.The Es4 formation in Y227 block is divided into 4 sand members,and the glutenite reservoirs mainly develop in Es4-3 and Es4-4.In whole the formation is high and thin in the north while low but thick in the south.Four types of lithofacies could be identified using core data and well logging data,including mudstone facies,pebbly sand facies of best reservoir quality,breccifrom sand facies of medium reservoir quality and conglomerate facies of worst reservoir quality.Then based on original methods of horizontal well data variogram analysis and glutenite reservoir model layering,Es4-3 and Es4-4 are divided into 6 layers.The reservoir model is built combining well data and seismic data after that.Through techniques of reservir evaluation basing on layer and well section,it is concluded that reservoirs in layer 2 and 4 are of best quality and largest scale;reservoirs in layer 3 are of medium quality and scale;layer 1,5 and 6 is worst in quality and scale.In addition,the quality and scale of the reservoir hit by the horizontal well control the production.2HF and 3HF wells hit the largest reservoir of high quality with the longest well section,so these two wells have biggest production;4HF and 6HF hit the good reservoir with medium well section and is also medium in production;1HF,8HF and 9HF hit relative good reservoir with short well section and are less good in production;5HF don't hit any good reservoir so is worst in production.