低孔渗砂岩储层基质物性下限确定方法研究——以川中LA构造沙一段油藏为例

METHODS OF DETERMINING THE MATRIX PETROPHYSICAL CUTOFFS OF LOW POROSITY AND LOW PERMEABILITY SANDSTONE RESERVOIR——TAKING THE J_2s^1 OIL RESERVOIR IN LA FIELD IN CENTRAL SICHUAN AS AN EXAMPLE

川中LA油田沙一段油藏为无边水、底水的构造岩性复合油藏,单井测试日产原油在几吨至上百吨之间。储层具典型的低孔低渗特征,产层段孔隙度一般在3%~6%之间,平均3.9%;渗透率集中在1.0×10-4~1.0×10-3μm2之间,平均2.64×10-4μm2。静态、动态资料及机理实验研究均反映出其储层类型为裂缝—孔隙型。本文在常规方法研究的基础上,开拓性采用了核磁共振、渗流能力模拟、岩心产能模拟等实验方法,明确了该油藏有效储层物性下限基质孔隙度为3%,基质渗透率为0.17×10-3μm2,为储量计算提供了依据。同时对低孔低渗储层评价也具重要意义。

The J_2s1 (first member of Shaximiao Formation, Middle Jurassic) oil reservoir in LA field in Central Sichuan is a structural-lithologic complex reservoir without edge water and bottom water, the single well test daily oil production ranging from several tons to about one hundred tons. The reservoir is typically characterized by low porosity and low permeability and the productive section has porosities of 3%-6%, averaging 3.9%, and permeabilities of 0.1×103—1.0×103 μm2, averaging 0.264×10 -3 μm2. According...