Fine Buried Hill Reservoir Evaluation Using Logging Data In M Sag

M sag is located in the oversea block of CNPC.In 2010,buried hill became one of exploration target strata.Buried hill reservoir exploration and development is regarded as one of an important domain for reserve growth and production addition.With the further exploration work,complexity of buried hill reservoir has been displayed.There are more than 40 kinds of rock determined by core analysis in buried hill reservoir of M sag and various reservoir space types like structural fracture,structural and dissolved fracture,broken intergranular pore and dissolved pore.It becomes an urgent technical problem to identify lithology and reservoir using logging data in M sag.In this paper,the method of lithology identification and classification standard were founded using conventional logging curve based on geological rock classification determined by core analysis.The method of reservoir identification and interpretation standard of different lithology was established by conventional and imaging logging data and test data.An optimal method was proposed to calculate porosity of the reservoir using three porosity logging curves and core analysis data.Through the study of lithology distribution,rock mechanical properties and fracture development,migmatitic granite,acid rock and mignatitic gneiss have more potential than other lithology in buried hill formation in M sag.A set of buried hill reservoir evaluation method using logging data was established and had a good result in exploration and development in M sag.This study can be used as the guide of logging interpretation and a logging support for further exploration and development of buried hill.The research results will be a reference for logging interpretation in buried hill in CNPC overseas block.