基于分形理论的致密砂岩储层微观孔隙结构表征——以冀中坳陷致密砂岩储层为例

发布时间：2018-04-13 18:29

  本文选题：致密砂岩 + 高压压汞　； 参考：《岩性油气藏》2017年05期

【摘要】：为了评价致密砂岩储层类型,为致密油气的勘探与开发提供理论依据,利用分形理论和高压压汞方法,结合储层物性资料,通过对11个致密砂岩样品的压汞实验,研究了冀中坳陷致密砂岩储层微观孔隙结构。结果表明:根据进汞曲线拐点,将致密砂岩储层孔隙系统按直径大小划分为裂隙(10μm)、大孔(1~10 μm)、中孔(0.1~1.0 μm)和微孔(0.1 μm)。依据分形理论,分别求取各尺度孔隙分形维数,验证了孔隙系统划分的正确性。根据不同尺度孔隙的分布频率,结合样品孔渗、排驱压力和退汞效率等参数将致密砂岩储层分为3类:Ⅰ类储层微孔分布频率高,但几乎无连通孔隙,具有较低的渗透率;Ⅱ类储层连通孔隙发育,但微孔较少;Ⅲ类储层不仅有大量微孔,同时有丰富的连通孔隙,渗透率也较高。通过分析得出,微孔分布频率越高,退汞效率越高,孔隙结构越简单,均质性越好;裂隙和大孔均决定了储层的渗流能力。因此,Ⅲ类致密砂岩储层为最优质的储层,可作为致密油气勘探与开采的首选目标。
[Abstract]:In order to evaluate the type of tight sandstone reservoir and provide theoretical basis for exploration and development of tight oil and gas, using fractal theory and high pressure mercury injection method, combined with reservoir physical property data, the mercury injection experiments of 11 tight sandstone samples were carried out.The micropore structure of tight sandstone reservoir in Jizhong Depression is studied.The results show that according to the inflexion point of mercury injection curve, the pore system of tight sandstone reservoir is divided according to its diameter into 10 渭 m fissures, 10 渭 m of macropore, 0.1 渭 m of mesopore, 0.1 渭 m of micropore and 0.1 渭 m of micropore.According to the fractal theory, the fractal dimension of pores at each scale is obtained, which verifies the correctness of pore system partition.According to the distribution frequency of pores at different scales, combined with sample porosity and permeability, the tight sandstone reservoirs can be classified into three categories: type I reservoirs with high distribution frequency of micropores, but almost no connected pores, with low permeability;The type 鈪，

本文编号：1745690