Reservoir Sensitivity Analysis of Tight Sandstone and Its Controlling Factors: A Case Study from Chang 4+5 to Chang 6 Reservoirs in N 212 Well Block of Nanniwan Oilfield, Ordos Basin

Table 1

Characteristics of pore structure parameters of tight sandstone on the basis of mercury pressure test.

Stratum	Parameters	Displacement pressure (MPa)	Skewness	Sorting coefficient	Median radius of throat (μm)
Chang 4+5	Maximum	5.07	1.91	0.18	0.12
	Minimum	0.64	1.64	0.02	0.02
	Mean	2.61	1.75	0.09	0.06
Chang 6	Maximum	5.22	2.43	0.14	0.13
	Minimum	0.71	1.09	0.02	0.01
	Mean	1.79	1.77	0.07	0.04