Drilling horizontal surface-to-inseam (SIS) wells along low permeability coal seams, e.g. <10 mD, is a crucial technology to increase the drainage area for this type of unconventional reservoir. For the first time in the Bowen Basin, a continuous 1900 m long formation resistivity-based high-resolution image log from a SIS well is used to investigate key coal reservoir characteristics including faults, fractures, coal plies, porosity and permeability. This study presents a workflow from image log interpretation to discrete fracture network (DFN) modelling and then to well performance analysis. The interpreted faults from the image logs were used to analyse the uncertainty of fault interpretation from 3D seismic data. The image log was also used in analysing the variation of fracture distribution vertically and horizontally and compared to similar data obtained from vertical wells. All these data were used to understand the variation in productions from three nearby chevron well groups. Results show that the fracture density decreases with increasing Gamma-ray response from the in-seam section, including the intra-seam partings. Regionally, the orientation of fractures and cleats is parallel, sub-parallel or even perpendicular to the regional maximum stress orientation; however, in the study area, the majority of fractures are generally parallel or near parallel to the maximum stress orientation. This study confirmed the trend that the orientation of fractures/cleats rotated from NE to NW from the study area to the north. Because the maximum stress orientation is NNE, this cleat orientation will yield a decrease in coal permeability from south to north. This can explain at least partially the decrease in well performance from south to north. Based on the modelled fractures and their apertures, the upscaled fracture porosity ranged from 0% to 0.01%, with fracture permeability in the x-direction (easting direction) ranging mainly from 1 mD to 10 mD, and with the ratio of permeability in the x-direction to y-direction (northing direction) ranging from 5 to 20.

沿低渗透煤层（例如<10 mD）钻探水平地表到内层（SIS）井是增加此类非常规储层泄油面积的关键技术。在 Bowen 盆地，首次使用来自 SIS 井的 1900 m 长的基于地层电阻率的连续高分辨率图像测井来研究关键煤储层特征，包括断层、裂缝、煤层、孔隙度和渗透率。本研究提出了从图像测井解释到离散裂缝网络 (DFN) 建模再到井动态分析的工作流程。图像测井解释断层用于分析 3D 地震数据断层解释的不确定性。图像测井还用于分析裂缝垂直和水平分布的变化，并与从垂直井获得的类似数据进行比较。所有这些数据都用于了解附近三个雪佛龙井组的产量变化。结果表明，裂缝密度随着来自煤层部分的伽马射线响应的增加而降低，包括煤层内分离。区域上，裂缝和割理的走向与区域最大应力方向平行、亚平行甚至垂直；然而，在研究区，大多数裂缝一般与最大应力方向平行或接近平行。本研究证实了裂缝/割理方向由研究区向北由NE向NW旋转的趋势。因为最大应力方向是 NNE，所以这种割理方向会导致煤的渗透率从南到北降低。这至少可以部分解释油井性能从南到北的下降。根据模拟的裂缝及其孔径，放大后的裂缝孔隙度范围为 0%～0.01%，x 向（东向）裂缝渗透率主要为 1～10mD，渗透率与x 方向到 y 方向（北向）范围为 5 到 20。