Abstract:

By comparing methods of qualitative and quantitative microfacies division，it is suggested that discriminant analysis can be used to build up microfacies for its

high efficient and correct dividing model in Chengdao Oilfield，in which，there are inclusive boundary，a lots wells and cored wells and multilayers．Sedimentation feature

can be characterized by more parameters，combined with the practice of Chengdao Oilfield and considering the difficulty from the cored wells to noncored wells，five

important parameters which include sand thickness，porosity，permeability，shaliness，medium size are selected as indicators of microfacies，at last，these parameters are

used to build up the discriminant function for four kinds of microfacies by using discriminant analysis，which attain an accuracy 86.7%．The quantitatively identified

microfacies are tested in 12 main layers in nearly 300 uncored wells of Chengdao Oilfield，the working efficiency is improved．

Key words: discriminant analysis, sedimentary microfacies, quantitative identification, Chengdao Oilfield