Abstract: Structural fractures play an important part in migration and accumulation ofhydrocar-bons in tight reservolrs and their porosities are key parameters in evaluation of oil pools.Theporosities of folded formations were estimated using methods proposed by Murray(1968) andothers,who have not taken into consideration a factor affecting estimation of the porosities,i.e.confining pressure.The authors emphasise significant effect of confining pressure on structural fracture porosities of folded layers and propose the formula(γ_x,γ_y,z)=e(z)/e(0)*(r_x,r_y) for estimation.

Key words: structure, fracture, porosity, curvity, confined pressure

摘要： 构造裂缝对致密储层中油气运移、聚集起着重要作用,裂缝孔隙度也是油藏评价的重要参数.以往的研究、计算方法,忽视了围压对构造裂缝孔隙度的影响.文中提出用曲率法或主曲率法等计算构造裂缝孔隙度应考虑岩层所处围压(深度)的重要影响.

关键词: 构造, 裂缝, 孔隙度, 曲率, 围压