摘要
研究了天然气在地下岩石中的扩散机理及影响因素 ,分析了源盖层对扩散相天然气封闭作用的特征 ,提出了源盖层具异常孔隙流体压力时 ,可对扩散相天然气形成浓度封闭作用 ,封闭能力与异常含气浓度成正比 ;当源盖层不具异常孔隙流体压力时 ,可对下伏扩散相天然气形成替代封闭作用 ,封闭能力与排气强度成正比 .利用异常含气浓度和排气强度建立了 2种评价源盖层封闭能力的方法 .实例应用表明 ,评价结果与实际状况吻合 .
Diffusion mechanism of gas and its effect on subsurface rocks were studied. Caprock with generation hydrocarbon ability and their seal to gas in diffusion phase were analysed. Concentration seal to gas in deffusion phase was put forward when caprock with generation hydrocarbon ability exerts abnormal pore flow pressure. There is a direct proportion between seal ability of caprock with generation hydrocarbon ability and abnormal gas-bearing concentration. Replacing seal to gas in diffusion phase was put forward when caprock with generation hydrocarbon ability has no abnormal pore flew pressure. There is a direct proportion between seal ability of caprock with generation hydrocarbon ability and expulsion gas strength. Two methods evaluating seal ability of caprock were established by using abnormal gas-bearing concentration and expulsion gas strength. Actual application indicates that evaluation results tally with actual geological conditions.
出处
《大庆石油学院学报》
CAS
北大核心
2003年第2期1-4,共4页
Journal of Daqing Petroleum Institute
基金
黑龙江省杰出青年基金项目 ( 2 0 0 0 -3 )
关键词
源盖层
扩散相天然气
浓度封闭作用
替代封闭作用
异常含气浓度
排气强度
caprock with generation hydrocarbon ability
gas in diffysion phase
concentration seal
replacing seal
abnormal gas-bearing concentration
expulsion gas strength
