Study on Micro Displacement Mechanism of Hydraulic Fracturing by Oil Displacement Agent at High Pressure

Table 2

Results of porosity and permeability measurements in natural cores.

Core number	The experimental scheme	Porosity measured with gas (%)	Overburden pressure porosity (%)	Effective permeability (×10^-3 μm^2)
17-1	Original state (predisplacement)	23.8	22.4	86.0
	Water driving under conventional injection rate	24.0	22.7	93.2
	Hydraulic fracturing by water at high pressure	25.5	24.5	134.6
	Hydraulic fracturing by oil displacement agent at high pressure	25.0	24.2	127.4
21-2	Original state (predisplacement)	24.6	23.8	113.6
	Water driving under conventional injection rate	25.0	24.1	120.2
	Hydraulic fracturing by water at high pressure	28.2	26.3	166.3
	Hydraulic fracturing by oil displacement agent at high pressure	29.4	26.5	175.5