0 引言
1 区域地质背景
2 泥页岩矿物组成及脆度分析
2.1 泥页岩矿物组成
图2 通化盆地下白垩统亨通山组泥页岩矿物成分组成(偶数号样品引自文献[9])Fig.2 Mineral composition of the shale in the Hengtongshan Formation, Lower Cretaceous, Tonghua Basin (even samples are quoted from Ref. [9]) |
表1 通化盆地亨通山组泥页岩微观孔隙结构参数及有机地球化学参数Table 1 Micro-pore structure parameters of shale in Hengtongshan Formation, Tonghua Basin |
样品号 | TD1 | TD5 | TD7 | TD11 | TD15 | TD19 | |
---|---|---|---|---|---|---|---|
深度/m | 216 | 293.3 | 326.6 | 425.7 | 584.1 | 587.8 | |
岩性 | 泥岩 | 泥岩 | 泥岩 | 泥岩 | 泥岩 | 泥岩 | |
TOC/% | 0.70 | 1.49 | 1.77 | 1.21 | 1.26 | 1.66 | |
T max/℃ | 441 | 459 | 455 | 462 | 466 | 458 | |
R O/% | 1.54 | 1.08 | 1.06 | 1.09 | 1.16 | 1.31 | |
BJH总孔容/(cm3/g) | 0.019 | 0.008 | 0.003 | 0.017 | 0.008 | 0.010 | |
BET比表面积/(m2/g) | 17.523 | 5.741 | 2.677 | 17.374 | 7.447 | 11.029 | |
平均孔径/(nm) | 5.435 | 7.868 | 5.877 | 4.881 | 5.771 | 5.385 | |
微孔/(<2nm) | 孔容/(cm3/g) | 0.019 | 0.008 | 0.003 | 0.016 | 0.008 | 0.010 |
比表面积/(m2/g) | 13.709 | 4.282 | 1.999 | 13.497 | 5.700 | 7.304 | |
中孔/(2~50nm) | 孔容/(cm3/g) | 0.210 | 0.107 | 0.033 | 0.172 | 0.089 | 0.101 |
比表面积/(m2/g) | 81.711 | 30.561 | 12.117 | 76.627 | 35.113 | 41.466 | |
大孔/(>50nm) | 孔容/(cm3/g) | 0.002 | 0.002 | 0.000 | 0.001 | 0.001 | 0.001 |
比表面积/(m2/g) | 0.121 | 0.100 | 0.026 | 0.080 | 0.055 | 0.060 | |
各孔段体积比/% | <2nm | 8.07 | 7.20 | 8.11 | 8.68 | 8.40 | 8.77 |
2~50nm | 91.12 | 91.47 | 90.81 | 90.67 | 90.74 | 90.42 | |
>50nm | 0.81 | 1.33 | 1.08 | 0.65 | 0.86 | 0.81 | |
各孔段比表面积比/% | <2nm | 14.35 | 12.26 | 14.14 | 14.96 | 13.95 | 14.96 |
2~50nm | 85.52 | 87.46 | 85.68 | 84.95 | 85.92 | 84.92 | |
>50nm | 0.13 | 0.29 | 0.18 | 0.09 | 0.13 | 0.12 |
2.2 脆度分析
3 泥页岩微观孔隙分布及类型
3.1 有机质孔
图5 通化盆地亨通山组泥页岩主要孔隙类型及分布(a)有机质孔,425.7m,0.055~0.354μm;(b)有机质孔,216m,0.052~0.225μm;(c)有机质孔,587.8m,0.090~0.980μm;(d)有机质与矿物颗粒间微裂缝,326.6m,0.160~0.706μm;(e)有机质内微裂隙,425.7m,0.027~0.169μm;(f)矿物溶蚀孔隙、粒间孔,216m,0.335~5.364μm;(g)矿物溶蚀孔隙,584.1m, 0.107~0.509μm;(h)黄铁矿晶间孔、铸模孔,293.3m ,0.081~1.530μm;(i)矿物粒间孔隙、溶蚀孔隙,293.3m ,0.122~1.213μm Fig.5 The pore types and distribution features of shale in the Hengtongshan Formation, Tonghua Basin |