煤层气开采关键地质影响因素

中国储量丰富的煤层气有着巨大的环保效益和资源潜力，但因独特的资源赋存条件，其规模化开采水平不高，亟待运用科学合理的方法来筛选出各类关键地质因素以实现开采创新。针对中国煤层气开采影响要素多、动态复杂性高等特点，构建了基于粗糙集属性约简的关键地质因素识别分析模型并进行了分析。首先从煤岩特征、煤层特征、地质影响3方面选取16个原始地质因素，以华北、西北、西南地区的40个煤层气井作为研究对象，对原始地质因素进行判定并构建决策数据，进而运用粗糙集数据分析工具集进行决策表属性约简，最终根据重要性进行排序并确定了关键地质影响因素。研究结果表明：地质构造类型、地应力、煤层孔隙及裂隙等8个地质因素重要度相对较高，且在煤层气开采过程中，外界的地质作用影响程度总体要比内部（如煤层与煤岩等）要大，因此，在实践过程中，应多关注于煤田外部地质因素的影响程度与作用方式，以期提升矿区瓦斯隐患治理水平。

Key geological factors influencing coal-bed methane exploitation

Coal-bed gas resources are huge in China.However,its scaled exploitation is limited due to unique occurrence status.Scientific methods are needed to identify the key geologic factors influencing its effective exploitation.In view of that the influencing factors are large in number and high in dynamic complexity,this paper established a model to identify and analyze the key geological factors based on rough set attribute reduction theory.First,sixteen original geologic factors were selected in respects of coal petrologic characteristics,coal seam features and geologic influences and were optimized according to the available data from 40 CBM wells selected for study in different regions of China.Then,decision data were constructed and attribute reduction of decision table was performed through rough set data analysis.Finally,sorting was performed according to their relative importance and the key influential geologic factors were identified.Eight geolo-gic factors including,geological structure type,in-situ stress,coal seam pores and fractures are relatively high in importance.Overall,external influential geologic factors have stronger power than internal ones such as coal seam and coal rock.Therefore,more attentions should be paid to the influence degree and action mode of the external geologic factors to enhance the level of mining gas hazard management in practice.