Difference of Microfeatures among Diagenetic Facies in Tight Sandstone Reservoirs of the Triassic Yanchang Formation in the Midwestern Region, Ordos Basin

Table 1

Sample information table.

Well number	Depth, m	Porosity, %	Gas permeability, ×10^−3 μm^2	Experimental test	Rock type	Sedimentary facies	Horizon
A144	2193.9	9.39	0.098	Microscopic water driving oil, NMR	Feldspar sandstone	Deltaic front subfacies	Chang 6
H393	2247.3	10.80	0.253
A36	1945.2	10.8	0.137	HPMI
Y182	2101.2	12.3	0.083
A211	1922.6	8.9	0.058		Lithic feldspar sandstone
Y144	2178.4	8.4	0.027
H185	2226.5	11.75	0.085	Microscopic water driving oil, NMR
H248	2037.1	10.08	0.023
A296	2197.6	10.6	0.126		Feldspar lithic sandstone		Chang 8
H26	2199.9	6.4	0.016