泥页岩储层有机孔隙定量评价研究

Quantitative Characterization of Organic Pores in Muddy Shale Reservoirs

泥页岩储层因其超低孔、超低渗和富含有机质以及其中页岩气赋存方式特殊等特点,使得泥页岩储层与常规砂岩储层的评价存在显著差别。为了对泥页岩中有机孔隙进行定量评价,以渝东南地区下志留统龙马溪组泥页岩为例,借助扫描电镜、化学动力学模型计算等技术和方法,分析泥页岩中的有机孔隙度。研究表明：渝东南地区下志留统龙马溪组泥页岩主要发育有机质孔隙和生物化石内孔隙2类有机孔隙;龙马溪组泥页岩有机孔隙的直径为0.01～5.00μm,以微孔、中孔为主;龙马溪组泥页岩有机孔隙度范围为0.05%～1.59%,平均值为0.71%,该层段泥页岩有机孔隙度偏低。

Muddy shale reservoir is characterized by ultra- low porosity,ultra- low permeability,organic- rich,multiple states of shale gas and other aspects,which lead to significant difference in reservoir characterization between shale and conventional sand-stone reservoirs. In order to quantitatively characterize the organic pores in muddy shale reservoirs,SEM,chemical kinetics model and other techniques and methods wereused to analyze the organic porosities of muddy shale samples from Lower Silurian Longmaxi Formation in southeastern Chongqing city. Research indicates that there are two kinds of organic pore and biological fossil pore in muddy shale from Lower Silurian LongmaxiF ormation in southeast Chongqing city. The diameters of organic pores in Longmaxi muddy shale are 0. 01- 5. 00 μm,and the dominant pores are micropores and mesopores. The organic porosity of Longmaxi shale is relatively low,mostly between 0. 05%- 1. 59%( average 0. 71%).