煤层气藏成藏过程研究

RESEARCH ON CBM RESERVOIRING PROCESS

煤层气藏成藏过程是反映煤层气富集成藏的演化史,研究高、低煤阶煤层气成藏过程及其差异性是研究煤层气富集成藏的重要组成部分。为此,以我国沁水、阜新盆地和美国粉河盆地为例,探讨了高、低煤阶煤层气的成藏过程,分析了现今地下水的补给、运移、排泄和滞流等格局对煤层气藏后期调整和改造所起的不同作用。研究表明,高煤阶气藏成藏过程复杂,且具有明显的阶段性,现今地下水格局对气藏的形成具有一定的影响;低煤阶气藏具有持续性的特征,地下水格局对气藏的调整和改造起到了决定性的影响。

CBM reservoiring process reflects the enrichment and reservoiring history of CBM. It is essential part for the CBM research to study on high coal rank and low coal rank CBM reservoiring and their comparison. Therefore, taking as examples the Qinshui Basin, Fuxin Basin in China, and the Powder River Basin in the U.S.A, it is discussed both high rank and low rank CBM reservoiring, and it is analyzed the different impacts of groundwater's supply, movement, drainage, and stagnant nowadays on the rebuilding and adjustment of the CBM reservoir afterwards. From the study, it shows that high rank CBM is quite complicated with obvious stages during its reservoiring process, and the present groundwater distributing pattern will play some roles in the formation of the CBM reservoirs; while low rank CBM reservoiring is of continuity, and the groundwater distributing pattern play crucial role in the rebuilding and adjustment of low rank CBM reservoirs, i.e. the immature CBM reservoiring process is very simple; while the mature CBM reservoiring process is between high rank and low rank immature CBM reservoirs.