Difficulties of log interpretation for glutenite fan reservoirs and solutions

Jiyang depression is structurally characterized by faulting in the north and overlapping in the south,having multiple categories of complicated glutenite fan reservoirs with special oil-water relationship widely developed in the northern steep slope.Due to extreme heterogeneity and the complexity of oil/gas distribution,the conventional log features of these reservoirs differ greatly from those of the ordinary sandstone reservoirs and the existing interpretation methods are not applicable.In this paper,a set of methods that can effectively identify the reservoirs,oil and water formations and interpret reservoir parameters have been proposed based on analyzing the changes of lithology of the glutenite fan reservoirs.These methods have been applied in practice and obviously the accuracy has improved,which has laid a foundation for further exploration and reserves estimation of glutenite fan reservoirs.