关键词: 特低渗透砂岩储层, 孔喉特征, 孔喉比, 孔隙结构, 特征参数, 储层性质

Abstract: The features of micro-pore throat in the ultra-low permeability sandstone reservoir were analyzed by using the constant-rate mercury injection technology.The effective throat radius,the effective throat volume,the effective pore radius,the effective pore volume and the pore-to-throat ratio are correlative with the porosity and permeability of reservoirs.For the rock samples with higher porosity and permeability,the effective throat and pores are better,while the pore-to-throat ratio is lower.The ultra-low permeability sandstone reservoirs are characterized by medium pore,fine throat,poor connectivity of pore with throat as well as great difference in properties of pore and throat.There will be the Jamin effect in the development of the ultra-low permeability reservoir.The quality of this kind of reservoir is mainly controlled by throat,and the radius of throat has the obvious classification features.When the permeability of reservoir gets lower,the correlation of throat radius with permeability gets better.The throat controls the permeability of reservoir and also determines the development effectiveness.

Key words: ultra-low permeability sandstone reservoir, pore throat features, pore-to-throat ratio, pore texture, characteristic parameter, reservoir property