Table 1. Basic Parameters.

type	parameter	value
proppant	density	2500 kg m–3
	size	40/70 mesh (average diameter of 0.3185 mm)
	sand ratio	10, 15, and 20%
fracturing fluid	viscosity	10 and 20 mPa s
	injection rate	0.3 m s–1
fracture	length of major fracture	50 cm
	length of branching fracture	15, 20, and 25 cm
	height of major fracture	6 cm
	height of branching fracture	6 cm
	width of major fracture	5 mm
	width of branching fracture	3 mm
	roughness	2.5
	angle of branching fracture	30, 45, and 90°
	closing pressure	20, 30, and 40 MPa