Pore throat structure and classification of Paleogene tight reservoirs in Jiyang depression, Bohai Bay Basin, China

WANG Yongshi,GAO Yang,FANG Zhengwei

Table 3 Experimental results of constant-rate mercury injection for tight Paleogene sandstone and sandy conglomerate in the Jiyang depression.

Reservoir type Sedimentation facies Sample number Depth/ m Poro- sity/% Permea- bility/ 10-3 μm2 Avg. throat radius/μm Avg. pore radius/μm Avg. pore- throat radius ratio/μm Avg. pore volume/nL Avg. pore throat radius/μm Main throat radius/μm Max. open throat radius/μm Max. mercury saturation/ % Sorting coeffi- cient Kurtosis Skew- ness Tight sandy conglomerate C660 4 304.1 2.4 0.009 138.182 10.641 0.127 0.136 28.679 0.009 1.000 1.000 Y22-22-1 3 485.5 3.6 0.099 145.785 16.961 0.942 2.437 26.647 0.612 1.892 0.325 Y22-22-2 3 506.9 5.9 0.112 0.751 142.422 224.453 13.985 0.365 0.055 0.886 48.765 0.175 2.329 0.317 Tight sandstone Shore-shallow lacustrine beach-bar microfacies B667-1 2 950.3 14.2 2.455 1.834 143.775 99.382 16.656 1.148 2.117 2.833 92.372 0.681 1.771 0.060 B667-2 2 956.0 4.9 0.014 131.818 11.074 0.131 0.144 7.815 0.013 1.000 1.000 Turbidite facies S548-1 3 346.1 10.9 0.186 0.468 143.691 329.978 16.839 0.330 0.177 0.608 63.132 0.115 2.034 0.686 S548-2 3 350.9 3.8 0.018 145.714 24.073 0.144 0.184 16.539 0.021 1.442 1.191 S126-1 3 445.9 7.1 0.046 0.342 141.149 441.159 14.053 0.225 0.103 0.340 39.845 0.062 1.796 0.578 S126-2 3 519.8 13.7 0.237 0.669 150.917 272.956 21.000 0.447 0.205 1.295 61.034 0.231 2.732 0.320 Deltaic front subfacies Y172-1 4 016.9 11.8 0.126 0.690 148.674 258.456 19.920 0.522 0.103 1.265 45.264 0.226 2.500 0.057 Y172-2 4 081.0 9.3 0.052 0.390 128.702 330.050 10.137 0.245 0.114 0.453 37.370 0.083 1.784 0.419