沁水盆地南部煤层气成藏的有效压力系统研究

有效压力系统是宏观动力能共同作用于煤储层而形成的压力体系，是联系煤储层地层能量与煤层气成藏的桥梁和纽带。它的主要影响因素为构造应力、地下水水头高度以及地下水矿化度。通过对沁水盆地南部有效压力系统的研究可以发现，影响煤层气藏形成和破坏的关键时期是晚侏罗世—早白垩世末，本阶段有效压力系统处于开放体系和封闭体系不断转换的状态，并因此造成煤储层孔裂隙大量形成，不仅为有效运移系统的形成奠定了基础，而且也为沁水盆地南部区域高煤级煤层气藏的可采性埋下了伏笔。

Effectual Stress System of Coalbed Methane in Southern Qinshui Basin

Effectual stress system,as the bridge of relating stratum energy and CBM reservoir formation,is formed by macroscopical dynamical energies which act on coal-bed.The main influencing factors of effectual stress system are tectonic stress,groundwater head height and groundwater mineralization.Researches of the effectual stress system in the southern Qinshui basin reveal that the key phase influencing on CBM reservoir forming and destroying was from the Late Jurassic to late Early Cretaceous,during this period the state of effectual stress system was continually transition between open-system and close-system,and formed a great deal of holes and crannies,which not only established the basis of effectual carrying system,but also foreshadowed the potential exploitation of high rank CBM reservoir in southern Qinshui basin.