中文摘要：

楔子是系统的，在煤缝接的自然破裂。他们说明大多数渗透和许多 coalbed 甲烷水库的孔并且能在水力的断裂的刺激的成功上有重要效果。水力的断裂试验的实验室在真 tri 轴的应力下面在煤块上被进行模仿煤缝接的断裂的刺激。破裂被与发光的黄注射水胶化开始荧光灯染料进 wellbore 的开的洞节。在煤缝接的水力的破裂的开始和繁殖上的楔子的影响被讨论。水力的破裂开始和繁殖模式的三种类型在这研究被观察：1 ) 沿着楔子开始然后成长的水力的破裂。2 ) 沿着一个靶子楔子开始的水力的破裂或破裂(由钻自然或导致) 面向粗略地在最小的水平压力方向，然后转弯了宣传它向最大的水平压力方向遇到了或逐渐地转弯了的第一个脸楔子。3 ) 对最小的压力垂直、当它遇到了一个脸楔子时，趋于的开始的水力的破裂如果延期方向不极大地背离，沿着楔子宣传(< 20

英文摘要：

Cleats are systematic, natural fractures in coal seams. They account for most of the permeability and much of the porosity of coalbed methane reservoirs and can have a significant effect on the success of hydraulic fracturing stimulation. Laboratory hydraulic fracturing experiments were conducted on coal blocks under true tri-axial stress to simulate fracturing stimulation of coal seams. Fractures were initiated by injecting a water gel with luminous yellow fluorescent dye into an open hole section of a wellbore. The impact of cleats on initiation and propagation of hydraulic fractures in coal seams is discussed. Three types of hydraulic fracture initiation and propagation pattern were observed in this study： 1） The hydraulic fracture initiated and then grew along the cleat. 2） The hydraulic fracture initiated along a butt cleat or a fracture （natural or induced by drilling） oriented roughly in the minimum horizontal stress direction, then turned to propagate along the first face cleat that it encountered or gradually turned towards the maximum horizontal stress direction. 3） The hydraulic fracture initiated perpendicular to the minimum stress and, when it encountered a face cleat, tended to propagate along the cleats if the extension direction does not deviate greatly （〈20° as determined in this paper） from the maximum horizontal stress direction. When a coal seam is hydraulically fractured, the resulting fracture network is controlled by the combined effect of several factors： cleats determine the initiation and extension path of the fracture, the in-situ stress state dominates the main direction of the fracture zone and bedding planes impede fracture height growth.