中国寻找大气田的前景及方向

THE PROSPECT AND DIRECTION OF FINDING GIANT GAS FIELDS IN CHINA

从生气母质、生气的窗口、聚集环境和流体的活动性等方面比较,天然气比石油具更广泛的成藏条件。中国大陆和海域的盆地特征、丰富的煤炭资源、发现的古隆起和圈闭类型,中国具有形成大气田的地质条件。但由于晚古生代以来中国板块构造复杂的演变,带来了储层物性不好和保藏条件欠佳两个不利因素,故中国至今尚未发现一些大气田。在今后的勘探工作中,作者提出(1)勘探稳定型盆地要与勘探活动型盆地兼顾;(2)选择层位上要注意石炭系和二叠系;(3)选择构造上要重视古隆起和其它圈闭的叠合部位;(4)注意深层中发现储层物性变好的地质和物理条件;(5)适当注意非烃气藏的勘探工作等5个方面为寻找气田的方向。

With respect to source material, maturation, accumulation and flowability, gas is more favorable than oil in forming hydrocarbon deposits. The wide occurrence of basins onland and offshore, abundance of coal resources, rich variety of paleolifts and traps, all favor the formation of giant gas fields However, complicated movement of plate tectonics in China since the late Paleozoic era resulted in poor reservoir properties and less favorable preservation, which can be the reason why no giant gas field is found in China. The author makes the following proposal: (1)pay equal attention to large basins and small basins, (2) lay stress on Carboniferous and Permian, (3)focus on the locations of paleo up lift superimposed with various traps, (4)turn to deep formations with improved geological and physical conditions, (5)explore for non-hydrocarbon gas.