Exploration and Development Research Institute, Daqing Oilfield Company Limited, Daqing 163712, Heilongjiang, China

 It has always been an indispensable research in reservoir research to determine the boundaries of key physical properties between conventional and tight, tight and ineffective reservoirs and establish the criteria of grouping evaluation, at home and abroad. Taking sandstone reservoirs of Nantun Formation in Wuerxun??Beier sag of Hailar Basin as an example, the key physical property boundaries of the sandstone reservoirs of Nantun Formation are determined by comprehensive application of mechanical balance, oil?bearing occurrence, minimum flow pore throat radius and other methods. It has been recognized that the porosity of 12% and permeability of 1 mD consti? tute the boundary between conventional and tight reservoirs, with 4% porosity and 0.03 mD permeability being that between tight and ineffective reservoirs. Based on the study above, the criteria of reservoir grouping evaluation were established by the internal structure characterization parameters of the reservoir obtained by high pressure Hg injec? tion, NMR and other experimental analysis. The sandstone reservoirs of the Nantun Formation are divided into five categories: conventional type Ⅰ (RQI≥1), conventional type Ⅱ (0.33≤RQI < 1), tight type Ⅰ, (0.13≤ RQI < 0.33) tight type Ⅱ (0.07≤RQI < 0.13), and ineffective type (RQI < 0.07), which reveal the macro? scopic physical properties and microscopic pore structure characteristics of different reservoir types. The oil test and production data confirm that the reservoir grouping scheme has a good correlation with production in oil test. Fur? thermore, it is clarified the adaptation testing technology of different types of reservoirs as follows. For conventional reservoir type I, industrial oil flow can be obtained by vertical wells routine testing. For conventional reservoir type Ⅱ, industrial oil flow requires a certain scale of fracturing. For tight reservoir type Ⅰ, industrial oil flow generally requires vertical well with large?scale fracturing. For tight reservoir type Ⅱ, industrial oil flow can be achieved by horizontal well with volume fracturing.