中国以成藏作用为核心的煤层气基础地质研究近些年取得显著进展。本源菌条件下褐煤生物气模拟、矿物/元素催化生气作用、无烟煤层重烃极度异常原因、煤层次生生物气等的研究成果,深化了对煤层气多元化成因的学术认识。在更为广泛的盆地和更加深入的层次上探讨了煤层气成藏作用的宏观地质过程及其控制因素,经典煤层气成藏作用理论得到发展。提出了原创性的煤层气成藏效应研究思路,从地层能量角度探讨了煤层气成藏作用的实质,提出了某些新的学术观点,初步探讨了深部煤层气成藏作用的特殊性。我国煤层气地质条件复杂多变,诸多基础地质问题尚待解决,近期探讨的重点在于宏观动力学方面的地应力场效应和深度效应,以及微观动力条件方面的煤级效应和粒度效应,涉及到深部、构造煤、低煤级煤等资源量巨大的煤层气成藏领域。同时,含煤地层非常规气(煤系气)的共生成藏关系以及共采中的基础地质问题,也将是今后的一个重点研究方向。
Basic geological research of coalbed methane (CBM) in China, taking the reservoir formation as a key, has made significant progress in recent years. The researches such as the biogenic gas simulation of the lignite samples under the condition of coalbed-derived methanogen, catalytic CBM generation from mineral and element, origin of extremely abnormal heavy hydrocarbons in anthracite seam, and secondary biogenic CBM, deepened greatly the academic understanding of the diverse CBM origins in China. Macro-process and its geological controls of the CBM reservoir formation were discussed in the more basins and deeper level, which promoted the development of the classical CBM reservoir fromation theories. Based on the original ideas, the essence of the CBM reservoir fromation was studied in the light of the formation energy, some new academic viewpoints were suggested, and the particularity of the deep CBM reservoir formation was investigated. Geological conditions of CBM in China are complex and changeable and many basic geological problems need to be further resolved. It was suggested that the recent exploration should focus on four aspects including the geo-stress field, burial depth, coal-rank and granularity effects. The first two effects belong to the macro-dynamics of CBM rerservoir formation and the latter two to the micro-dynamics, which involves to the fields of the deep, tectonically deformed and low-rank coal reservoirs with a huge amount of CBM resources. Meanwhile, the basic geological problems related to the paragenetic reservoiring and co-mining of the unconventional natural gases in coal-bearing strata (coal-measures gas) will also be a focus of the CBM research in the future.