Base on the combination of total porosity measurement and high-pressure mercury injection for shales,a quantitative study method focusing on shale's pore structure and pore connectivity is established in this paper.The paper compares the total porosity,effective pore diameter distribution and pore connecting rate among the massive mudstone,laminar shale and laminated shale of Paleogene Shahejie formation in Dongying depression.The study shows that the massive shale has the lowest porosity ranging from 2.7％ to 4.5％,laminated shale has the highest porosity ranging from 10.2％ to 17.7％,and the porosity of the laminar shale is 5.9％～11.2％.The massive mudstone is dominated by pores of small pore diameter with the the main peak value less than 10.0 nm.The pore diameter of the laminated shale ranges from 3.6 to 10000.0 nm with the main peak higher than 10.0 nm,and the proportion of pore diameter less than 10.0 nm is relatively low.The pore diameter of the laminar shale is distributed between those of massive and laminated shales,its main peak value is usually about 10 nm,the proportion of the pores with the diameter less than 10.0 nm in the laminar shale is lower than that of the massive mudstone,and the proportion of the pores with the diameter higher than 100.0 nm in the laminar shale is lower than that of the laminated shale.The massive mudstone has the lowest pore connecting rate,the laminated shale has the highest pore connecting rate and the laminar shale has the medium rate.The differences of the shale's pore structure characteristics are related to sedimentary lithofacies and diagenesis.There are a few primary and syngenetic pores in the massive mudstone,which is not good for the formation of secondary pores.The pore structures of laminar and laminated shales are favorable for the preservation of primary pore and the formation of secondary pore.%以泥页岩总孔隙度测定和高压压汞分析相结合,建立了页岩储集层孔隙结构特征的量化研究方法.对比了东营凹陷古近系沙河街组块状泥岩、层状页岩和纹层状页岩的总孔隙度、有效孔径分布和孔隙连通率.研究表明:块状泥岩孔隙度最低,为2.7％～4.5％;纹层状页岩孔隙度最高,为10.2％～17.7％;层状页岩孔隙度为5.9％～11.2％.块状泥岩以小孔径的孔隙为主,其主峰值一般小于10.0 nm;而纹层状页岩孔径分布最宽,在3.6～10000.0 nm,孔径主峰值大于10.0 nm,并且孔径小于10.0 nm孔隙所占比例相对较低;层状页岩的孔径分布特点介于块状泥岩和纹层状页岩之间,其主峰值一般在10.0 nm左右,孔径小于10.0nm孔隙所占比例低于块状泥岩,孔径大于100.0 nm孔隙比例低于纹层状页岩.块状泥岩的孔隙连通率最低,纹层状页岩的孔隙连通率最高,层状页岩介于二者之间.泥页岩的孔隙结构特征差异与沉积岩相和成岩作用有关,块状泥岩原生及同生孔隙较少,且不利于次生孔隙的形成,纹层状页岩和层状页岩则有利于原生孔隙的保存和次生孔隙的形成.
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