Table 4.

Data obtained for the remaining oil in different displacement stages using the laser confocal microscopy technique.

Displacement State	Recovery Degree (%)	Remaining Oil Saturation Content (%)
		Bound Remaining Oil			Semibound Remaining Oil		Free Remaining Oil
		Membranelike	Particle-Adsorbent-Like	Slitlike	Corner-Shaped	Throatlike	Clusterlike	Intergranular-Adsorption-Like
Water flooding	16.81	14.14	3.79	2.14	6.52	4.38	23.33	4.81
Heavy oil activator flooding	34.31	10.26	3.61	1.84	4.75	3.28	18.58	3.62
Subsequent water flooding	39.76	9.38	3.44	1.70	3.76	2.78	17.27	3.48