华北地区石炭-二叠系天然气资源、成藏特征及勘探策略

RESOURCES, TRAPPING CHARACTERISTICS AND EXPLORATION STRATEGICS OF THE C-P NATURAL GAS IN HUABEI REGION

华北地区石炭-二叠系煤系气具有相当大的资源潜力。常规煤系气藏和煤层甲烷是两种截然不同的资源类型,其富集因素及勘探方法完全不同。由于华北地区中新生代的构造演化及沉积发育史分异作用,分别形成了持续沉降一次生气成藏、间断沉降二次生气成藏和后期抬升脱气成藏三种不同的成藏模式。研究认为,针对其不同的成藏特点,应采用不同的勘探策略。

Carboniferous-permian coal formed gas in north china has a great resource potential. Conventional coal measures gas reservoir and coal-seam methane are definitely different in their types of resources, and so it is quite distinct in their accumulation factors and exploration technique. Three different models for the formation of gas reservoir are suggested, i.e.: reservoir formation due to primary gas generation with continued subsidence, reservoir formation due to secondary gas generation with intermittent subsidence, and reservoir formation by degassing in later uplifting process, because of the different structural evolution and the differentiation of depositional history in this area. The author suggests in the paper that different exploration strategies should be selected for gas reservoirs with different characteristics of reservoir formation.