多煤层煤层气有利区评价方法研究与应用

Study and Application of Evaluation Parameters for CBM Favorable Area in Multi-layer Coal Seam

根据川南煤田煤层气赋存特征,结合现行规程规范,选择了符合本区地质特征的有利区评价参数。针对本区煤层多、厚度薄、间距小、单层评价潜力有限,提出了"首要参数一票否决+多层次模糊评价体系+多层空间叠加"作为有利区评价方法。通过实例应用,分煤层对大村区块有利区进行了预测和综合评价排序,多层空间叠加优选出的Ⅰ类有利区可作为近期勘探开发的目标区,Ⅱ、Ⅲ类有利区可作为中远期煤层气勘探开发的对象。选区结果与取得的勘探试验成果吻合度较高,评价方法应用及其验证效果较好。

According to the occurrence characteristics of CBM in the south of Sichuan Coalfield and the current relevant regulations and standards,the evaluation parameters of favorable area are selected. Aiming at the fact that there are multiple and thin coal seams with small spacing and limited potential for single layer evaluation in this area,the method of ＂primary parameter one-vote-down ＋ multi-level fuzzy evaluation system ＋ multi-layer space superposition＂is proposed as a favorable area evaluation method.Through practical application,the prediction and comprehensive evaluation of the favorable area of Dacun Block are made by the divided coal seams. Class I favorable area selected by multi-layer space superposition can be regarded as the target area for the recent exploration and development,Class II and III favorable areas can be used as the targets for the exploration and exploitation of CBM in middle and long term.The results show good agreement with the experimental results obtained,and the application of the evaluation method and its verification results are good.