中国大中型气田盖层特征

Cap Rock Characteristics of Medium and Large Gas Fields in China

在对我国主要大中型气田盖层的岩性、厚度等宏观参数统计分析与排替压力、扩散系数等微观参数的实验分析基础上,对我国大中型气田盖层分布进行定性和定量研究,认为我国大中型气田盖层分布具有以泥岩为主、盖层厚度大(大部分分布在50~350 m之间)、排替压力较高(主要分布在10~30 MPa之间)、大中型气田扩散系数普遍较低(主要小于10-6cm2/s)和岩性大中型气田相对其他类型大中型气田在盖层厚度和排替压力等方面要求相对较低等特征。

Based on the statistics of cap rock parameters of medium-and large-size gas fields in China,the qualitative and quantitative evaluations of the cap rock sealing capacity have been studied.The cap rock lithology of most medium and large gas fields is mudstone and the thickness of the cap rocks ranges from 50m to 350m.The displacement pressure of the cap rocks is high and ranges from 10MPa to 30MPa.The diffusion coefficient of the medium and large gas fields is generally less than 10-6 cm2/s.The cap rock cond...