In order to develop an experimental method for measuring saturation exponent, a porous plate method for capillary pressure-resistivity connection survey and a centrifuge method were used respectively to determine the saturation index for four low permeability reservoirs, and the differences in the measurements were compared accordingly. In addition, the different mechanism and applicability of these two methods were analyzed using the saturation measurements from well logs. The re-sults show that the centrifuge method is not applicable when the permeability is lower than 2×10-3 μm2 to 4×10-3 μm2 be-cause of the disequilibrium of capillary pressure and resistivity, as well as the effect of evaporation. However, the porous plate method is preferably applicable when the work pressure is not higher than the breakthrough pressure. The porous plate method can provide both saturation index and capillary pressure curve, which can be used to determine the reservoir type and its saturation index, thus can be applied to deal with heterogeneity in reservoirs.%为了开发低渗透储层饱和度指数测量方法,分别应用半渗透隔板法毛管压力-电阻率联测和离心法测量4种典型低渗透储层的饱和度指数 n,对比分析饱和度指数测量结果的差异性和机制,结合储层饱和度测井评价考察方法的适应性。结果表明：对于2×10-3~4×10-3μm2以上的低渗透岩心,两种方法均适用；当渗透率小于2×10-3~4×10-3μm2时,由于存在毛管压力与电阻率不平衡和“蒸发”的影响,离心法的适应性变差,隔板法仍然适用,但适应性会受到隔板突破压力的限制；隔板法能够同时提供毛管压力曲线用于划分储层类型,并给出相应的饱和度指数,有助于应对低渗透储层的非均质性。
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