Effect of Threshold Pressure Gradients on Control Areas Determination of Production Well in CBM Reservoirs

Table 1

Some geological information of the Nos. 3 and 15 coal seams.

Erathem	System	Formation	Formation thickness	Coal seam thickness
Paleozoic	Lower permian	Lower shihezi	40–110 m	—
		Shanxi	30–70 m	No. 3 : 4 –6.6 m
	Upper carboniferous	Taiyuan	80–130 m	No. 15 : 2.2 –10 m
	Middle carboniferous	Benxi	0–45 m	—