中国大气田勘探方向

EXPLORATION ORIENTATION FOR LARGE GAS FIELDS IN CHINA

国家新一轮资源评价的结果表明,中国的天然气资源量为56×1012m3,由于天然气资源勘探程度低,目前资源探明率平均为10%,所以今后天然气勘探发展潜力大。截至2006年底,全国已发现天然气藏223个,探明天然气地质储量5.4×1012m3,其中探明地质储量1000×108m3以上的大气田有9个。中国目前发现的天然气储量主要分布在扬子、塔里木和华北三大古板块,它们的探明天然气地质储量占全国总储量的70%,大气田也主要分布在这三大古板块之中。中国三大古板块长期处于构造相对稳定区,海相烃源岩发育,有多套储集层;发育以膏盐岩为主的盖层;存在大型构造、地层圈闭,具有形成大气田的有利条件。三大古板块之中的川渝区、塔里木区和鄂尔多斯区已发现了大量的天然气田。这些区块也是中国天然气未来勘探的重点目标。

China has huge natural gas resources,and the latest statistics shows the quantity of long-term prospects of natural gas resource in China is 56 tcm.China has low natural gas exploration level,with a rate of discovered resource at 10% in average.Therefore it has enormous untapped potential.Up till the end of 2006,223 gas reservoirs had been discovered with the explored reserves of 5.4 tcm,among which total 9 large gas fields with the explored reserves of 100 bcm gad been found out.These great discoveries are mainly distributed in Yangtzi,Tarim and Huabei palaeoslabs,which take up70% of the proven reserves.The three palaeoslabs have advantageous conditions for giant gas fields,which have been located in the stable geological structure for a long time,developed marine facies source rock,and there are many sets of reservoirs,in which the developed gypsolith is mainly as a cap;there are large-scale structural and stratigraphic-lithologic traps.Many gas fields have been discovered in the three palaeoslabs,such as the Sichuan and Chongqing,the Tarim Basin,and the Ordos Basin,and they will also be the promising areas for natural gas exploration in the future.